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Sample records for rat mastomys natalensis

  1. Mastomys natalensis and Lassa fever, West Africa.

    PubMed

    Lecompte, Emilie; Fichet-Calvet, Elisabeth; Daffis, Stéphane; Koulémou, Kékoura; Sylla, Oumar; Kourouma, Fodé; Doré, Amadou; Soropogui, Barré; Aniskin, Vladimir; Allali, Bernard; Kouassi Kan, Stéphane; Lalis, Aude; Koivogui, Lamine; Günther, Stephan; Denys, Christiane; ter Meulen, Jan

    2006-12-01

    PCR screening of 1,482 murid rodents from 13 genera caught in 18 different localities of Guinea, West Africa, showed Lassa virus infection only in molecularly typed Mastomys natalensis. Distribution of this rodent and relative abundance compared with M. erythroleucus correlates geographically with Lassa virus seroprevalence in humans. PMID:17326956

  2. Mastomys natalensis and Lassa Fever, West Africa

    PubMed Central

    Fichet-Calvet, Elisabeth; Daffis, Stéphane; Koulémou, Kékoura; Sylla, Oumar; Kourouma, Fodé; Doré, Amadou; Soropogui, Barré; Aniskin, Vladimir; Allali, Bernard; Kan, Stéphane Kouassi; Lalis, Aude; Koivogui, Lamine; Günther, Stephan; Denys, Christiane; ter Meulen, Jan

    2006-01-01

    PCR screening of 1,482 murid rodents from 13 genera caught in 18 different localities of Guinea, West Africa, showed Lassa virus infection only in molecularly typed Mastomys natalensis. Distribution of this rodent and relative abundance compared with M. erythroleucus correlates geographically with Lassa virus seroprevalence in humans. PMID:17326956

  3. Comparative pathogenicity of Trypanosoma brucei rhodesiense strains in Swiss white mice and Mastomys natalensis rats.

    PubMed

    Muchiri, Margaret Wanjiku; Ndung'u, Kariuki; Kibugu, James Karuku; Thuita, John Kibuthu; Gitonga, Purity Kaari; Ngae, Geoffrey Njuguna; Mdachi, Raymond Ellie; Kagira, John Maina

    2015-10-01

    We evaluated Mastomys natelensis rat as an animal model for Rhodesian sleeping sickness. Parasitaemia, clinical and pathological characteristics induced by T. b. rhodesiense isolates, KETRI 3439, 3622 and 3637 were compared in Mastomys rats and Swiss white mice. Each isolate was intra-peritonially injected in mice and rat groups (n=12) at 1×10(4) trypanosomes/0.2mL. Pre-patent period (PP) range for KETRI 3439 and KETRI 3622-groups was 3-6 days for mice and 4-5 days for rats while for KETRI 3637-infected mice and rats was 5-9 and 4-12 days, respectively. Pairwise comparison between PP of mice and rats separately infected with either isolate showed no significant difference (p>0.05). The PP's of KETRI 3637-infected mice were significantly (p>0.01) longer than those infected with KETRI 3439 or KETRI 3622, a trend also observed in rats. The second parasitaemic wave was more prominent in mice. Clinical signs included body weakness, dyspnoea, peri-orbital oedema and extreme emaciation which were more common in rats. Survival time for KETRI 3439 and 3622-infected groups was significantly (p<0.05) longer in mice than rats but similar in KETRI 3637-infected groups. Inflammatory lesions were more severe in rats than mice. All mice and KETRI 3622-infected rats had splenomegaly, organ congestion with rats additionally showing prominent lymphadenopathy. KETRI 3439-infected rats showed hemorrhagic pneumonia, enteritis with moderate splenomegaly and lymphadenopathy. KETRI 3637-infected rats had the most severe lesions characterized by prominent splenomegaly, lymphadenopathy, hepatomegaly, enlarged adrenal glands, organ congestion, generalized oedemas, gastroenteritis, pneumonia and brain congestion. KETRI 3637-infected Mastomys is a suitable model for studying pathophysiology of HAT. PMID:26099681

  4. Arenavirus Diversity and Phylogeography of Mastomys natalensis Rodents, Nigeria

    PubMed Central

    Obadare, Adeoba; Oyeyiola, Akinlabi; Igbokwe, Joseph; Fasogbon, Ayobami; Igbahenah, Felix; Ortsega, Daniel; Asogun, Danny; Umeh, Prince; Vakkai, Innocent; Abejegah, Chukwuyem; Pahlman, Meike; Becker-Ziaja, Beate; Günther, Stephan; Fichet-Calvet, Elisabeth

    2016-01-01

    Mastomys natalensis rodents are natural hosts for Lassa virus (LASV). Detection of LASV in 2 mitochondrial phylogroups of the rodent near the Niger and Benue Rivers in Nigeria underlines the potential for LASV emergence in fresh phylogroups of this rodent. A Mobala-like sequence was also detected in eastern Nigeria. PMID:26982388

  5. The ecology of Praomys (Mastomys) natalensis in southern Africa

    PubMed Central

    Isaäcson, Margaretha

    1975-01-01

    The only non-human host of Lassa virus so far identified is the multimammate mouse, Praomys (Mastomys) natalensis, but its precise role in the natural Lassa fever cycle remains to be determined. This species is also an important link in the plague cycle in southern Africa and is one of the commonest rodents of Africa. It is a prolific breeder and can be kept and bred easily in captivity. It is thus an excellent laboratory animal, although it needs to be handled with care because it is aggressive towards man and bites readily. The current status of knowledge of its taxonomy, ecology, distribution, and role as a disease vector is reviewed, but attention is drawn to the possibly disastrous consequences of attempting to eradicate a vector species before the natural cycle of the disease and the ecology of the vector are fully understood. ImagesFig. 2 PMID:1085218

  6. Chemotherapeutic studies on Litomosoides carinii infection of Mastomys natalensis*

    PubMed Central

    Lämmler, Georg; Herzog, Heike; Saupe, Eberhard; Schütze, Hans Rudolf

    1971-01-01

    The antifilarial action of 2-[2-(4-hydroxyphenyl)-6-benzimidazolyl]-6-(1-methyl-4-piperazyl) benzimidazole (HOE 33258) was investigated in Mastomys natalensis infected with Litomosoides carinii. The subcutaneous administration of HOE 33258 in a single daily dose for 5 consecutive days, or at other intervals, produced, depending on the dosage, a rapid reduction in the number of microfilariae in the circulating blood. The reduction amounted to more than 90% within 7-14 days after the treatment was started or at the end of the dosage schedule. The small, slow increase in the microfilarial count during a period of 6-7 weeks after treatment ended reached not more than half the number present before treatment. HOE 33258 showed marked activity on the reproductive system of mature female worms, although only few macrofilariae were killed by the drug. The results also demonstrated the usefulness of L. carinii infection of M. natalensis as a model for the evaluation of the filaricidal activity of drugs. PMID:5317445

  7. Spontaneous diseases in a closed colony of Praomys (Mastomys) natalensis

    PubMed Central

    Snell, K. C.; Stewart, H. L.

    1975-01-01

    In comparison with other rodents, the mastomys is unique as regards the patterns of neoplastic and non-neoplastic diseases that it develops, some of which may constitute suitable animal models for corresponding diseases of man. Among the spontaneous diseases commonly encountered in necropsies of 600 mastomys maintained in a closed colony were: (1) degenerative joint disease of diarthroses and interventricular disks, which develops regularly in the second year of life; (2) renal disease, a type of immune-complex glomerulonephritis, affecting approximately 80% of mastomys in the age bracket 18-36 months; (3) thymomas and thymic hyperplasia affecting 30% of mastomys by the time they are 2 years old or older; (4) a combination of thymoma and polymyositis in a mastomys showing serum-globulin reactivity, presumably auto-antibody against striated muscle; (5) beginning before the age of 1 year, replacement of the normal cell population of the lymphoid tissues by plasma cells, and intense plasma cell infiltration at many other organ and tissue sites; (6) haematopoietic neoplasms, without leukaemic blood, in 10% of mastomys; and (7) histamine-producing argyrophilic carcinoid tumours of the glandular stomach in approximately 60% of old male and 30% of old female mastomys. Additionally, other neoplasms not infrequently encountered in mastomys rarely occur in other rodent species; conversely some neoplasms commonly found in other rodents, including especially tumours of the lung and mammary gland and leukaemia, are rare or absent in mastomys. PMID:1085220

  8. Laboratory test of seven rodenticides for the control of Mastomys natalensis.

    PubMed

    Gill, J E; Redfern, R

    1979-10-01

    Laboratory feeding tests were carried out to assess the efficacy of seven rodenticides against Mastomys natalensis. The poisons (warfarin, coumatetralyl, difenacoum, brodifacoum, bromadiolone, calciferol and zinc phosphide) were all toxic at the concentrations normally used against Rattus norvegicus (Berk.), although several were unpalatable. Trials are now needed to demonstrate the relative efficacy of these poisons in the field, but it is likely that, given suitable bait formulations, they would all be useful as practical control agents. PMID:489963

  9. Laboratory test of seven rodenticides for the control of Mastomys natalensis.

    PubMed Central

    Gill, J. E.; Redfern, R.

    1979-01-01

    Laboratory feeding tests were carried out to assess the efficacy of seven rodenticides against Mastomys natalensis. The poisons (warfarin, coumatetralyl, difenacoum, brodifacoum, bromadiolone, calciferol and zinc phosphide) were all toxic at the concentrations normally used against Rattus norvegicus (Berk.), although several were unpalatable. Trials are now needed to demonstrate the relative efficacy of these poisons in the field, but it is likely that, given suitable bait formulations, they would all be useful as practical control agents. PMID:489963

  10. Host evolution in Mastomys natalensis (Rodentia: Muridae): An integrative approach using geometric morphometrics and genetics.

    PubMed

    Lalis, Aude; Evin, Allowen; Janier, Marc; Koivogui, Lamine; Denys, Christiane

    2015-11-01

    The commensal rodent Mastomys natalensis is the natural reservoir of Lassa arenavirus (LASV), which causes hemorrhagic fever in West Africa. To study a possible effect of the virus on phenotypic and genotypic variation of its persistently infected host, we compared LASV-positive and non-infected wild-caught M. natalensis. The LASV effects on the phenotypic variation were explored using standard external morphometric measurements, geometric morphometric analyses of the cranial size and shape, and brain case volume. The genetic variability of M. natalensis specimens was assessed using 9 polymorphic microsatellite markers. Independent of sex and age, LASV-infected animals had smaller external body measurements, reproductive organs, skull size and brain case volume. Cranial shape differences between the 2 groups are represented by a lateral constriction of the entire skull. The genetic variability revealed consanguinity only among the LASV-positive rodents. We hypothesize that growth impairment may result in a selective disadvantage for LASV-infected M. natalensis, leading to a preferably commensal lifestyle in areas where the LAVS is endemic and, thereby, increasing the risk of LASV transmission to humans. PMID:26331855

  11. Transcriptome analysis of Mastomys natalensis papillomavirus in productive lesions after natural infection.

    PubMed

    Salvermoser, Melanie; Chotewutmontri, Sasithorn; Braspenning-Wesch, Ilona; Hasche, Daniel; Rösl, Frank; Vinzón, Sabrina E

    2016-07-01

    Mastomys coucha, an African rodent, is a useful animal model of papillomavirus infection, as it develops both premalignant and malignant skin tumors as a consequence of a persistent infection with Mastomys natalensis papillomavirus (MnPV). In this study, we mapped the MnPV transcriptome in productive lesions by both classical molecular techniques and high-throughput RNA sequencing. Combination of these methods revealed a complex and comprehensive transcription map, with novel splicing events not described in other papillomaviruses. Furthermore, these splicing occurrences could potentially lead to the expression of novel E2, E1∧E4, E7 and L2 isoforms. Expression level estimation of each transcript showed that late-region mRNAs considerably outnumber early transcripts, with species coding for L1 and E1∧E4 being the most abundant. In summary, the full transcription map assembled in this study will allow us to further understand MnPV gene expression and the mechanisms that lead to natural tumour development. PMID:27043420

  12. Trichuris spp. (Nematoda: Trichuridae) from two rodents, Mastomys natalensis and Gerbilliscus vicinus in Tanzania.

    PubMed

    Ribas, Alexis; López, Sergi; Makundi, Rhodes H; Leirs, Herwig; de Bellocq, Joëlle Goüy

    2013-10-01

    During a survey of the helminth community of several rodent species in the Morogoro region (Tanzania), Trichuris whipworms (Nematoda: Trichuridae) were found in the ceca of the Natal multimammate mouse, Mastomys natalensis and a gerbil, Gerbilliscus vicinus (both Rodentia: Muridae). The taxonomic literature regarding Trichuris from African native rodents describes 10 species, but includes few metric and morphologic characters that discriminate between some of the pairs. The whipworms we sampled in Tanzanian Natal multimammate mice and gerbils were morphologically identified, respectively, as Trichuris mastomysi Verster, 1960 and Trichuris carlieri Gedoelst, 1916 sensu lato, but with characters that overlap or partially overlap with the cosmopolitan Murinae whipworm, Trichuris muris , already reported from several rodents in Africa. To clarify our identification, we sequenced the ITS-1, 5.8S, and ITS-2 ribosomal DNA region of the worms' nuclear genome. The genetic analyses clearly distinguish the whipworms we found in M. natalensis from those found in the gerbil, and both of these from T. muris whipworm reference sequences. The overlap of morphological characters between rodent whipworms suggests that reports of T. muris from rodent species not closely related to Murinae in other parts of Africa should be treated with caution. PMID:23560615

  13. Chemotherapeutic studies on Litomosoides carinii infection of Mastomys natalensis. 8. The action of furazolidone on adult worms and microfilariae.

    PubMed

    Wegerhof, P H; Lämmler, G; Sänger, I; Zahner, H

    1979-09-01

    After oral administration of furazolidone in doses of 5 x 50 mg/kg and 1 x 100 mg/kg body weight to Litomosoides carinii--infected Mastomys natalensis microfilaraemia decreased continuously and was reduced by more than 98% 42 days after start of treatment. After the 5-day treatment all adult female and male worms were found dead and encapsulated within 2 weeks, whereas after the single dose 100% of the female parasites were encapsulated 28 days after treatment. In untreated animals quantiative examinations of the intrauterine stages showed an average number of 500 x 103 embryos per adult female worm. Following the 5-day treatment the number of embryos per female parasite was reduced after 42 days to 12.5 x 103, and after the single treatment to 26.9 x 103. By classification into 5 different stages (2- and 4-cell stages, Morula stage, "Horse-shoe" stage, "Ring" and "Brezel" stages, and intruterine microfilariae) an embryogram showed a continuous increase in pathologically-altered embryos during the whole observation period. The 2- and 4-cell stages suffered the most damaged. By 16 days after the end of the 5-day treatment and by 28 days after the single treatment all embryonic stages in the uteri were found to be pathologically altered. Furazolidone possessess high macrofilaricidal activity together with a considerable adverse effect on embryognesis and some delayed effect on microfilaraemia. PMID:543002

  14. Increased Incidence of Squamous Cell Carcinomas in Mastomys natalensis Papillomavirus E6 Transgenic Mice during Two-Stage Skin Carcinogenesis

    PubMed Central

    Helfrich, Iris; Chen, Min; Schmidt, Rainer; Fürstenberger, Gerhard; Kopp-Schneider, Annette; Trick, David; Gröne, Hermann-Josef; zur Hausen, Harald; Rösl, Frank

    2004-01-01

    Papillomaviruses cause certain forms of human cancers, most notably carcinomas of the uterine cervix. In contrast to the well-established involvement of papillomavirus infection in the etiology of cervical carcinomas and in carcinomas of a rare hereditary condition, epidermodysplasia verruciformis, a causative role for cutaneous human papillomavirus types in the development of nonmelanoma skin cancer has not been proven. In order to better understand the functions of individual genes of cutaneous papillomavirus types, we generated transgenic mice carrying oncogene E6 of the Mastomys natalensis papillomavirus (MnPV), which causes keratoacanthomas of the skin in its natural host. In the present study, we demonstrate that under conditions of experimental two-stage skin carcinogenesis, fast-paced squamous cell carcinomas develop in nearly 100% of MnPV E6 transgenic mice in comparison to 10% in their nontransgenic littermates (log rank test; P < 0.0001). Therefore, we conclude that the MnPV E6 transgene favors the malignant progression of chemically induced tumors. Whereas an activating H-ras mutation is a consistent feature in benign and malignant tumors in wild-type mice, the majority of papillomas and keratoacanthomas and all squamous cell carcinomas obtained in MnPV E6 transgenic mice contain nonmutated ras alleles. These results indicate that the development of squamous cell carcinomas in MnPV E6 transgenic mice does not depend on an activated H-ras oncogene. PMID:15078961

  15. The Impact of Human Conflict on the Genetics of Mastomys natalensis and Lassa Virus in West Africa

    PubMed Central

    Denys, Christiane; ter Meulen, Jan; Wirth, Thierry

    2012-01-01

    Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago). Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease. PMID:22615894

  16. The impact of human conflict on the genetics of Mastomys natalensis and Lassa virus in West Africa.

    PubMed

    Lalis, Aude; Leblois, Raphaël; Lecompte, Emilie; Denys, Christiane; Ter Meulen, Jan; Wirth, Thierry

    2012-01-01

    Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago). Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease. PMID:22615894

  17. Effect of aqueous extract of Bulbine natalensis (Baker) stem on the sexual behaviour of male rats.

    PubMed

    Yakubu, M T; Afolayan, A J

    2009-12-01

    The phytochemical constituents of aqueous extract of Bulbine natalensis (Baker) stem and its effect on male rat sexual behaviour were evaluated for 7 days. Phytochemical screening revealed the presence of saponins, cardiac glycoside, tannins, alkaloids and anthraquinones. Administration of the extract at the doses of 25 and 50 mg/kg body weight resulted in the significant increase (p < 0.05) in mount frequency, intromission frequency, ejaculatory latency, ejaculation frequency, serum testosterone and luteinizing hormone concentrations, computed indices of sexual behaviour, erection, quick flips, long flips and total penile reflexes whereas the mount latency, intromission latency and post-ejaculatory interval were significantly decreased (p < 0.05) throughout the experimental period. The 100 mg/kg body weight of the extract produced contrasting pattern to the lower doses of the extract in all the parameters of sexual behaviour monitored throughout the experimental period. The results are indicative of prosexual stimulatory potentials of Bulbine natalensis in male rats. The aqueous extract of Bulbine natalensis stem at these doses (25 and 50 mg/kg body weight) may be used in the management of disorders of desire/libido, premature ejaculation and erectile dysfunction in males. PMID:18710410

  18. Immune responses of two Mastomys sibling species to Yersinia pestis.

    PubMed Central

    Arntzen, L; Wadee, A A; Isaäcson, M

    1991-01-01

    This study assessed the in vitro cell-mediated immune responses of Mastomys natalensis, with a diploid chromosome number of 2n = 32, and Mastomys coucha, with a diploid chromosome number of 2n = 36, to Yersinia pestis. Splenic mononuclear (MN) cells of uninfected M. natalensis proliferated in response to crude fraction 1 of Y. pestis and two subfractions derived from fraction 1 in vitro. Proliferation was dose dependent and followed the time kinetics of other well-known mitogens. Further characterization of the two fractions revealed similar protein profiles in sodium dodecyl sulfide-polyacrylamide gel electrophoresis and indicated a heat-stable protein of 25 kDa responsible for the mitogenic activity. No such response was observed with MN cells from M. coucha. The unresponsiveness of M. coucha-derived MN cells appears to be related to an inability to respond to Y. pestis organisms. The results may help explain the relative resistance and susceptibility of M. natalensis and M. coucha to Y. pestis infection. Images PMID:2037358

  19. Care of Mastomys in the laboratory.

    PubMed

    Scholz, Jodi; Wilson, Steven

    2016-05-20

    Mastomys rodents occupy a valuable niche in biomedical research, but there is very little published information regarding how to care for them in the laboratory. Here we provide information about the physical and behavioral characteristics of this unusual laboratory rodent, its taxonomic history, common diseases that affect it, and its use in research. We also provide housing recommendations based upon almost 15 years of experience successfully maintaining a colony of Mastomys coucha at our institution. PMID:27203263

  20. Antimicrobial activity of the solvent fractions from Bulbine natalensis Tuber.

    PubMed

    Yakubu, M T; Mostafa, M; Ashafa, A O T; Afolayan, A J

    2012-01-01

    Bulbine natalensis Baker has been acclaimed to be used as an antimicrobial agent in the folklore medicine of South Africa without scientific evidence to substantiate or refute this claim. In view of this, the in vitro antimicrobial activity of solvent fractions (ethanol, ethyl acetate, n-butanol and water) from Bulbine natalensis Tuber against 4 Gram positive and 12 Gram negative bacteria as well as 3 fungal species were investigated using agar dilution. The ethanolic extract, n-butanol and ethyl acetate fractions inhibited 75, 87.5 and 100% respectively of the bacterial species in this study. The ethanolic, n-butanol and ethyl acetate fractions produced growth inhibition at MIC range of 1-10, 3-10 as well as 1 and 5 mg/ml respectively whereas the water fraction did not inhibit the growth of any of the bacterial species. Again, it was only the ethyl acetate fraction that inhibited the growth of Shigelli flexneri, Staphyloccus aureus and Escherichia coli. The ethanolic, ethyl acetate and n-butanolic fractions dose dependently inhibited the growth of Aspergillus niger and A. flavus whereas the water fraction produced 100% growth inhibition of the Aspergillus species at all the doses investigated. In contrast, no growth inhibition was produced on Candida albicans. The growth inhibition produced by the solvent fractions of B. natalensis Tuber in this study thus justifies the acclaimed use of the plant as an antimicrobial agent. The ethyl acetate fraction was the most potent. PMID:23983381

  1. Establishment of an Immortalized Skin Keratinocyte Cell Line Derived from the Animal Model Mastomys coucha

    PubMed Central

    Hasche, Daniel; Stephan, Sonja; Savelyeva, Larissa; Westermann, Frank; Rösl, Frank

    2016-01-01

    In the present report we describe the establishment of a spontaneous immortalized skin keratinocyte cell line derived from the skin of the multimammate rodent Mastomys coucha. These animals are used in preclinical studies for a variety of human diseases such as infections with nematodes, bacteria and papillomaviruses, especially regarding cutaneous manifestations such as non-melanoma skin cancer. Here we characterize the cells in terms of their origin and cytogenetic features. Searching for genomic signatures, a spontaneous mutation in the splicing donor sequence of Trp53 (G to A transition at the first position of intron 7) could be detected. This point mutation leads to alternative splicing and to a premature stop codon, resulting in a truncated and, in turn, undetectable form of p53, probably contributing to the process of immortalization. Mastomys coucha-derived skin keratinocytes can be used as an in vitro system to investigate molecular and immunological aspects of infectious agent interactions with their host cells. PMID:27533138

  2. Establishment of an Immortalized Skin Keratinocyte Cell Line Derived from the Animal Model Mastomys coucha.

    PubMed

    Hasche, Daniel; Stephan, Sonja; Savelyeva, Larissa; Westermann, Frank; Rösl, Frank; Vinzón, Sabrina E

    2016-01-01

    In the present report we describe the establishment of a spontaneous immortalized skin keratinocyte cell line derived from the skin of the multimammate rodent Mastomys coucha. These animals are used in preclinical studies for a variety of human diseases such as infections with nematodes, bacteria and papillomaviruses, especially regarding cutaneous manifestations such as non-melanoma skin cancer. Here we characterize the cells in terms of their origin and cytogenetic features. Searching for genomic signatures, a spontaneous mutation in the splicing donor sequence of Trp53 (G to A transition at the first position of intron 7) could be detected. This point mutation leads to alternative splicing and to a premature stop codon, resulting in a truncated and, in turn, undetectable form of p53, probably contributing to the process of immortalization. Mastomys coucha-derived skin keratinocytes can be used as an in vitro system to investigate molecular and immunological aspects of infectious agent interactions with their host cells. PMID:27533138

  3. Activity of Redox Enzymes in the Thallus of Anthoceros natalensis.

    PubMed

    Chasov, A V; Beckett, R P; Minibayeva, F V

    2015-09-01

    Anthocerotophyta (hornworts) belong to a group of ancient nonvascular plants and originate from a common ancestor with contemporary vascular plants. Hornworts represent a unique model for investigating mechanisms of formation of stress resistance in higher plants due to their high tolerance to the action of adverse environmental factors. In this work, we demonstrate that the thallus of Anthoceros natalensis exhibits high redox activity changing under stress. Dehydration of the thallus is accompanied by the decrease in activities of intracellular peroxidases, DOPA-peroxidases, and tyrosinases, while catalase activity increases. Subsequent rehydration results in the increase in peroxidase and catalase activities. Kinetic features of peroxidases and tyrosinases were characterized as well as the peroxidase isoenzyme composition of different fractions of the hornwort cell wall proteins. It was shown that the hornwort peroxidases are functionally similar to peroxidases of higher vascular plants including their ability to form superoxide anion-radical. The biochemical mechanism was elucidated, supporting the possible participation of peroxidases in the formation of reactive oxygen species (ROS) via substrate-substrate interactions in the hornwort thallus. It has been suggested that the ROS formation by peroxidases is an evolutionarily ancient process that emerged as a protective mechanism for enhancing adaptive responses of higher land plants and their adaptation to changing environmental conditions and successful colonization of various ecological niches. PMID:26555468

  4. Susceptibility of two-week old Lymnaea natalensis to some plant extracts.

    PubMed

    Kela, S L; Ogunsusi, R A; Ogbogu, V C; Nwude, N

    1989-01-01

    The molluscacidal potency of 17 Nigerian plants extracted by the unevaporated crude water (UECW) method was evaluated on two-week old Lymnaea natalensis Krauss. Five extracts were not active but extracts of Balanites aegytiaca, Blighia sapida, Boswellia dalzielii, Cissampelos mucronata, Detarium microcarpum, Kigelia africana, Opilia celtidifolia, Parkia clappertoniana, Polygonum limbatum, Pseudocedrela kotschyi, Nauclea latifolia and Securidaca longipedunculata were molluscacidal. There is potential for their future use in the integrated control of Lymnaea natalensis, as well as other snails. Mortality data for lethal concentration values for all extracts were analysed by use of probit transformation. The upper and lower fiducial limits of the LC50 (P = 0.05) were also determined. PMID:2626571

  5. Comparative toxicity of Paraquat herbicide and some plant extracts in Lymnaea natalensis snails.

    PubMed

    Bakry, Fayez A; Eleiwa, Mona E; Taha, Samir A; Ismil, Somya M

    2016-01-01

    Paraquat has been shown to be a highly toxic compound for humans and animals, and many cases of acute poisoning and death have been reported over the past few decades. The present study was undertaken to evaluate comprehensively herbicides (Paraquat) and some plant extracts to biochemical aspects of Lymnaea natalensis snails. It was found that the exposure of L. natalensis to Paraquat and plant extracts led to a significant reduction in the infectivity of Fasciola gigantica miracidia to the snail. The glucose level in hemolymph of exposed snails was elevated, while the glycogen showed a decrease in soft tissues when compared with the control group. In addition, the activity level of some enzymes representing glycolytic enzymes as hexokinase (HK), pyruvate kinase (PK), phosphofructokinase (PFK), lactate dehydrogenase (LDH), and glucose phosphate isomerase (GPI) in snail's tissues were reduced in response to the treatment. It was concluded that the pollution of the aquatic environment by herbicide would adversely affect the metabolism of the L. natalensis snails. Snails treated with Agave attenuate, Ammi visnaga, and Canna iridiflora plant had less toxic effect compared to snails treated with Paraquat. PMID:24081640

  6. Reflecting optics in the diverticular eye of a deep-sea barreleye fish (Rhynchohyalus natalensis)

    PubMed Central

    Partridge, J. C.; Douglas, R. H.; Marshall, N. J.; Chung, W.-S.; Jordan, T. M.; Wagner, H.-J.

    2014-01-01

    We describe the bi-directed eyes of a mesopelagic teleost fish, Rhynchohyalus natalensis, that possesses an extensive lateral diverticulum to each tubular eye. Each diverticulum contains a mirror that focuses light from the ventro-lateral visual field. This species can thereby visualize both downwelling sunlight and bioluminescence over a wide field of view. Modelling shows that the mirror is very likely to be capable of producing a bright, well focused image. After Dolichopteryx longipes, this is only the second description of an eye in a vertebrate having both reflective and refractive optics. Although superficially similar, the optics of the diverticular eyes of these two species of fish differ in some important respects. Firstly, the reflective crystals in the D. longipes mirror are derived from a tapetum within the retinal pigment epithelium, whereas in R. natalensis they develop from the choroidal argentea. Secondly, in D. longipes the angle of the reflective crystals varies depending on their position within the mirror, forming a Fresnel-type reflector, but in R. natalensis the crystals are orientated almost parallel to the mirror's surface and image formation is dependent on the gross morphology of the diverticular mirror. Two remarkably different developmental solutions have thus evolved in these two closely related species of opisthoproctid teleosts to extend the restricted visual field of a tubular eye and provide a well-focused image with reflective optics. PMID:24648222

  7. Reflecting optics in the diverticular eye of a deep-sea barreleye fish (Rhynchohyalus natalensis).

    PubMed

    Partridge, J C; Douglas, R H; Marshall, N J; Chung, W-S; Jordan, T M; Wagner, H-J

    2014-05-01

    We describe the bi-directed eyes of a mesopelagic teleost fish, Rhynchohyalus natalensis, that possesses an extensive lateral diverticulum to each tubular eye. Each diverticulum contains a mirror that focuses light from the ventro-lateral visual field. This species can thereby visualize both downwelling sunlight and bioluminescence over a wide field of view. Modelling shows that the mirror is very likely to be capable of producing a bright, well focused image. After Dolichopteryx longipes, this is only the second description of an eye in a vertebrate having both reflective and refractive optics. Although superficially similar, the optics of the diverticular eyes of these two species of fish differ in some important respects. Firstly, the reflective crystals in the D. longipes mirror are derived from a tapetum within the retinal pigment epithelium, whereas in R. natalensis they develop from the choroidal argentea. Secondly, in D. longipes the angle of the reflective crystals varies depending on their position within the mirror, forming a Fresnel-type reflector, but in R. natalensis the crystals are orientated almost parallel to the mirror's surface and image formation is dependent on the gross morphology of the diverticular mirror. Two remarkably different developmental solutions have thus evolved in these two closely related species of opisthoproctid teleosts to extend the restricted visual field of a tubular eye and provide a well-focused image with reflective optics. PMID:24648222

  8. Evaluation of an Experimental Gel Containing Euclea natalensis: An In Vitro Study

    PubMed Central

    Sales-Peres, Sílvia Helena de Carvalho; Brianezzi, Letícia Ferreira de Freitas; Marsicano, Juliane Avansini; Forim, Moacir Rossi; da Silva, Maria Fatima das Graças Fernandes; Sales-Peres, Arsenio

    2012-01-01

    Objective. To evaluate the effect of an experimental gel containing Euclea natalensis extract on dentin permeability. Methods. Thirty-six dentin discs, 1-mm-thick. The discs were prepared from the coronal dentin of extracted human third molars that were divided into 3 groups (n = 10). The dentin discs in each group were treated with the groups following experimental materials: (FG): 1.23% fluoride gel, pH 4.1; (EG): Euclea natalensis extract gel, pH 4.1; (CG): control gel, pH 4.1. The gels were applied to the occlusal slide of the dentin under the following conditions: after 37% phosphoric acid and before 6% citric acid. The hydraulic conductance (HC) of each condition was determined four times using a fluid flow apparatus (Flodec). The data were analyzed using Two-way ANOVA and Tukey's test (P < 0.05). Results. The greatest mean reduction in HC was produced in group EG dentin discs (61.2%; P < 0.05). Even after acid challenge with 6% citric acid the great reduction occurred in group EG (66.0%; P < 0.05) than other groups (CG-77.1%, FG-90.8%). Conclusion. E. natalensis gel not only reduced dentin permeability, but also resisted posttreatment citric acid challenge without changing its permeability. Further research has to confirm this promising result in the clinical situation. PMID:23243432

  9. Erosion and abrasion-inhibiting in situ effect of the Euclea natalensis plant of African regions.

    PubMed

    Sales-Peres, Silvia Helena de Carvalho; Xavier, Cheila Nilza Hamina; Mapengo, Marta Artemisa Abel; Forim, Moacir Rossi; Silva, Maria de Fatima; Sales-Peres, Arsenio

    2016-06-14

    This study evaluated the effect of Euclea natalensis gel on the reduction of erosive wear with or without abrasion, in enamel and dentin. During two five-day experimental crossover phases, volunteers (n = 10) wore palatal devices containing human enamel and dentin blocks (E = 8 and D = 8). The gel was applied in a thin layer in the experimental group, and was not applied in the control group. In the intraoral phase, volunteers used the palatal appliance for 12 h before the gel treatment, and were instructed to start the erosive challenges 6 h after the gel application. Erosion was performed with Coca-Cola® (for 5 min) 4 times/day. The appliance was then put back into the mouth and was brushed after 30 minutes. After intraoral exposure, the appliances were removed and the specimens were analyzed using profilometry (mean ± SD, μm). The Euclea natalensis gel caused less wear in enamel in the experimental group (EROS = 12.86 ± 1.75 µm; EROS + ABRAS = 12.13 ± 2.12 µm) than in the control group (EROS = 14.12 ± 7.66 µm; EROS + ABRAS = 16.29 ± 10.72 µm); however, the groups did not differ from each other significantly. A statistically significant value was found for erosion and eros + abrasion in dentin (p = 0.001). Euclea natalensis may play a role in the prevention of dentin loss under mild erosive and abrasive conditions. A clinical trial is required to confirm these promising results in a clinical situation. PMID:27305512

  10. Setaria digitata microfilaraemia in Mastomys coucha: an animal model for chemotherapeutic and immunobiological studies.

    PubMed

    Mukhopadhyay, S; Dash, A P; Ravindran, B

    1996-10-01

    Intraperitoneal implantation of adult gravid females of the bovine filarial parasite, Setaria digitata in Mastomys coucha was found to induce microfilaraemia lasting for about 125 days. The microfilariae (mf) could be detected as early as 4 days post-implantation (p.i.) and peak levels of about 30 mf in 20 microliters of blood were observed by 21 days. A significant positive correlation was found between mf density and the body weight of recipients pre-implantation. The implanted adult worms were generally viable only for less than 1 week. Implantation resulted in a significant decrease in total leucocytes and erythrocytes, induction of eosinophilia, splenomegaly and anti-erythrocyte autoantibodies. The microfilariae in circulation developed into 3rd-stage infective larvae (L3) when fed onto Aedes aegypti (refm, Liverpool strain). The mf in circulation were found to be eliminated by oral administration of diethylcarbamazine citrate, indicating the usefulness of this model for screening potential anti-microfilarial drugs. During the microfilaraemic phase, priming with tetanus toxoid (TT) resulted in significantly decreased production of anti-toxin levels indicating a state of generalized immunosuppression. Induction of antibodies to various fractionated antigenic components of adult parasites could be demonstrated by enzyme immunoassay (EIA) in M. coucha implanted with live or cold-stunned adult worms. The S. digitata-M. coucha model thus is found amenable to perform chemotherapeutic and immunobiological investigations in experimental filariasis. PMID:8873474

  11. Streptomyces natalensis programmed cell death and morphological differentiation are dependent on oxidative stress

    PubMed Central

    Beites, Tiago; Oliveira, Paulo; Rioseras, Beatriz; Pires, Sílvia D. S.; Oliveira, Rute; Tamagnini, Paula; Moradas-Ferreira, Pedro; Manteca, Ángel; Mendes, Marta V.

    2015-01-01

    Streptomyces are aerobic Gram-positive bacteria characterized by a complex life cycle that includes hyphae differentiation and spore formation. Morphological differentiation is triggered by stressful conditions and takes place in a pro-oxidant environment, which sets the basis for an involvement of the oxidative stress response in this cellular process. Characterization of the phenotypic traits of Streptomyces natalensis ΔkatA1 (mono-functional catalase) and ΔcatR (Fur-like repressor of katA1 expression) strains in solid medium revealed that both mutants had an impaired morphological development process. The sub-lethal oxidative stress caused by the absence of KatA1 resulted in the formation of a highly proliferative and undifferentiated vegetative mycelium, whereas de-repression of CatR regulon, from which KatA1 is the only known representative, resulted in the formation of scarce aerial mycelium. Both mutant strains had the transcription of genes associated with aerial mycelium formation and biosynthesis of the hyphae hydrophobic layer down-regulated. The first round of the programmed cell death (PCD) was inhibited in both strains which caused the prevalence of the transient primary mycelium (MI) over secondary mycelium (MII). Our data shows that the first round of PCD and morphological differentiation in S. natalensis is dependent on oxidative stress in the right amount at the right time. PMID:26256439

  12. Crosstalk between ROS Homeostasis and Secondary Metabolism in S. natalensis ATCC 27448: Modulation of Pimaricin Production by Intracellular ROS

    PubMed Central

    Santos, Catarina L.; Osório, Hugo; Moradas-Ferreira, Pedro; Mendes, Marta V.

    2011-01-01

    Streptomyces secondary metabolism is strongly affected by oxygen availability. The increased culture aeration enhances pimaricin production in S. natalensis, however the excess of O2 consumption can lead to an intracellular ROS imbalance that is harmful to the cell. The adaptive physiological response of S. natalensis upon the addition of exogenous H2O2 suggested that the modulation of the intracellular ROS levels, through the activation of the H2O2 inducible catalase during the late exponential growth phase, can alter the production of pimaricin. With the construction of defective mutants on the H2O2 related enzymes SodF, AhpCD and KatA1, an effective and enduring modulation of intracellular ROS was achieved. Characterization of the knock-out strains revealed different behaviours regarding pimaricin production: whilst the superoxide dismutase defective mutant presented low levels of pimaricin production compared to the wild-type, the mutants defective on the H2O2-detoxifying enzymes displayed a pimaricin overproducer phenotype. Using physiological and molecular approaches we report a crosstalk between oxidative stress and secondary metabolism regulatory networks. Our results reveal that the redox-based regulation network triggered by an imbalance of the intracellular ROS homeostasis is also able to modulate the biosynthesis of pimaricin in S. natalensis. PMID:22114674

  13. Antioxidant study of flavonoid derivatives from the aerial parts of Rhus natalensis growing in Saudi Arabia.

    PubMed

    Alqasoumi, Saleh Ibrahim; Basudan, Omer Ahmed; Alam, Prawez; Abdel-Kader, Maged Saad

    2016-01-01

    Phytochemical study of the CH(2)Cl(2) soluble fraction of the aerial parts of R. natalensis resulted in the isolation and identification of six flavonoid derivatives, β-amyrin and β-sitosterol glucoside (daucosterol). The isolated compounds were identified utilizing physical, chemical and different spectral methods including UV, 1D- 2D-NMR and MS. The compounds were identified as four flavanones; 7-O-methyl hesperetin (1), 7-O-methyl naringenin (4), (-)-homoeriodictyol (eriodictyonone) (5), eriodictyol-7-methyl ether (6) and two flavones; 7-O-methyl isokaemferide (2) and genkwanin (3). The isolated compounds as well as some available standards representing structurally similar flavones and flavanones were used to study their antioxidant potential using DPPH and try to explore the impact of structures on the antioxidant activity. In other assays flavanones were less active than flavones as antioxidant due to lack of the C-4 carbonyl group in conjugation with 2,3-double bond. However, in DPPH assay based on the ability of molecules to donate hydrogen flavanones were found more active than flavones. PMID:26826843

  14. The complete mitochondrial genome of fungus-growing termite, Macrotermes natalensis (Isoptera: Macrotermitinae).

    PubMed

    Meng, Ziye; Jiang, Shihong; Chen, Xiaoqin; Lei, Chaoliang

    2016-05-01

    In this study, the complete mitochondrial genome of a fungus-growing termite, Macrotermes natalensis, with the total length of 16,325 bp, is reported for the first time. This mtgenome harbors 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). The total base composition is 44.1% of A, 21.5% of T, 11.5% of G, and 22.9% of C, so the percentage of A and T (65.6%) is much higher than that of G and C. Most of the genes are distributed on H-strand, except for four subunit genes (ND1, ND4, ND4L, ND5) and eight tRNA genes. All protein-coding genes start with an ATN codon, and terminate with the canonical stop codon (TAA/TAG) or a single T (T- -). The complete mitochondrial genome sequence reported here adds a new genetic resource for the genus Macrotermes and might be useful for phylogenetic and systematic analyses within the genus Macrotermes. PMID:25259453

  15. The Effect of Different Host Plants on Development and Survival of Nysius natalensis (Hemiptera: Orsillidae).

    PubMed

    Du Plessis, Hannalene; Byrne, Marcus; Van Den Berg, Johnnie

    2015-02-01

    Nysius natalensis Evans (Hemiptera: Orsillidae) is a pest of sunflower in South Africa. Adults invade sunflower fields from their weedy hosts. The host plant suitability for development and survival and the effect of between-generation host switching were studied on different wild host plants and sunflower. Parameters used to assess host plant suitability were nymphal development, head widths, mean mass, and survival. Nymphs and adults were provided with crushed seed of five host plants, as well as a combination of seeds of the five species. Duration of the nymphal stage, development and mortality, and mean development time to adult were recorded. Between-generation host switching was studied by providing first-instar nymphs (F2) with seed of either the same plant species or transferred to different ones. Mean mass and mean head widths of adults (F2) were determined. The food source during the first and second generation, as well as the interaction thereof, has a significant effect on head widths of resultant males and females, as well as on female mass, but first-generation food did not have a significant effect on male mass. Feeding the F2 on sunflower proved to be beneficial to the false chinch bug, as it provided the heaviest males and females as well as females with the biggest head widths. Lack of constant availability of moisture had a detrimental effect on longevity. Host plant switching to sunflower likely happens as a result of senescence of wild host plants prior to winter. PMID:26308814

  16. Development of cycad ovules and seeds. 2. Histological and ultrastructural aspects of ontogeny of the embryo in Encephalartos natalensis (Zamiaceae).

    PubMed

    Woodenberg, Wynston Ray; Berjak, Patricia; Pammenter, N W; Farrant, Jill M

    2014-07-01

    Development of the embryo of Encephalartos natalensis from a rudimentary meristematic structure approximately 700 μm in length extends over 6 months after the seed is shed from the strobilus. Throughout its development, the embryo remains attached to a long suspensor. Differentiation of the shoot meristem flanked by two cotyledonary protuberances occurs over the first 2 months, during which peripheral tannin channels become apparent. Tannins, apparently elaborated by the endoplasmic reticulum, first accumulate in the large central vacuole and ultimately fill the channel. By the fourth month of development, the root meristem is apparent and procambial tissue forming discrete vascular bundles can be discerned in the elongating cotyledons. Between 4 and 6 months, mucilage ducts differentiate; after 6 months, when the seed becomes germinable, the embryo is characterised by cotyledons far longer than the axis. Shoot and root meristem cells remain ultrastructurally similar throughout embryo ontogeny, containing small vacuoles, many well-differentiated mitochondria and endoplasmic reticulum (ER) profiles, abundant polysomes, plastids containing small starch deposits and Golgi bodies. Unusually, however, Golgi bodies are infrequent in other cells including those elaborating mucilage which is accumulated in distended ER and apparently secreted into the duct lumen directly by ER-derived vesicles. The non-meristematic cells accumulate massive starch deposits to the exclusion of any protein bodies and only very sparse lipid, features which are considered in terms of the prolonged period of embryo development and the high atmospheric oxygen content of the Carboniferous Period, when cycads are suggested to have originated. PMID:24240517

  17. New Hosts of The Lassa Virus.

    PubMed

    Olayemi, Ayodeji; Cadar, Daniel; Magassouba, N'Faly; Obadare, Adeoba; Kourouma, Fode; Oyeyiola, Akinlabi; Fasogbon, Samuel; Igbokwe, Joseph; Rieger, Toni; Bockholt, Sabrina; Jérôme, Hanna; Schmidt-Chanasit, Jonas; Garigliany, Mutien; Lorenzen, Stephan; Igbahenah, Felix; Fichet, Jean-Nicolas; Ortsega, Daniel; Omilabu, Sunday; Günther, Stephan; Fichet-Calvet, Elisabeth

    2016-01-01

    Lassa virus (LASV) causes a deadly haemorrhagic fever in humans, killing several thousand people in West Africa annually. For 40 years, the Natal multimammate rat, Mastomys natalensis, has been assumed to be the sole host of LASV. We found evidence that LASV is also hosted by other rodent species: the African wood mouse Hylomyscus pamfi in Nigeria, and the Guinea multimammate mouse Mastomys erythroleucus in both Nigeria and Guinea. Virus strains from these animals were isolated in the BSL-4 laboratory and fully sequenced. Phylogenetic analyses of viral genes coding for glycoprotein, nucleoprotein, polymerase and matrix protein show that Lassa strains detected in M. erythroleucus belong to lineages III and IV. The strain from H. pamfi clusters close to lineage I (for S gene) and between II &III (for L gene). Discovery of new rodent hosts has implications for LASV evolution and its spread into new areas within West Africa. PMID:27140942

  18. New Hosts of The Lassa Virus

    PubMed Central

    Olayemi, Ayodeji; Cadar, Daniel; Magassouba, N’Faly; Obadare, Adeoba; Kourouma, Fode; Oyeyiola, Akinlabi; Fasogbon, Samuel; Igbokwe, Joseph; Rieger, Toni; Bockholt, Sabrina; Jérôme, Hanna; Schmidt-Chanasit, Jonas; Garigliany, Mutien; Lorenzen, Stephan; Igbahenah, Felix; Fichet, Jean-Nicolas; Ortsega, Daniel; Omilabu, Sunday; Günther, Stephan; Fichet-Calvet, Elisabeth

    2016-01-01

    Lassa virus (LASV) causes a deadly haemorrhagic fever in humans, killing several thousand people in West Africa annually. For 40 years, the Natal multimammate rat, Mastomys natalensis, has been assumed to be the sole host of LASV. We found evidence that LASV is also hosted by other rodent species: the African wood mouse Hylomyscus pamfi in Nigeria, and the Guinea multimammate mouse Mastomys erythroleucus in both Nigeria and Guinea. Virus strains from these animals were isolated in the BSL-4 laboratory and fully sequenced. Phylogenetic analyses of viral genes coding for glycoprotein, nucleoprotein, polymerase and matrix protein show that Lassa strains detected in M. erythroleucus belong to lineages III and IV. The strain from H. pamfi clusters close to lineage I (for S gene) and between II & III (for L gene). Discovery of new rodent hosts has implications for LASV evolution and its spread into new areas within West Africa. PMID:27140942

  19. Rat-atouille: A Mixed Method Study to Characterize Rodent Hunting and Consumption in the Context of Lassa Fever.

    PubMed

    Bonwitt, Jesse; Kelly, Ann H; Ansumana, Rashid; Agbla, Schadrac; Sahr, Foday; Saez, Almudena Mari; Borchert, Matthias; Kock, Richard; Fichet-Calvet, Elisabeth

    2016-06-01

    Lassa fever is a zoonotic hemorrhagic illness predominant in areas across Nigeria, Sierra Leone, Guinea, Liberia, and southern Mali. The reservoir of Lassa virus is the multimammate mouse (Mastomys natalensis), a highly commensal species in West Africa. Primary transmission to humans occurs through direct or indirect contact with rodent body fluids such as urine, feces, saliva, or blood. Our research draws together qualitative and quantitative methods to provide a fuller and more nuanced perspective on these varied points of human-animal contact. In this article, we focus on the hunting, preparation, and consumption of rodents as possible routes of exposure in Bo, Sierra Leone. We found that the consumption of rodents, including the reservoir species, is widespread and does not neatly tally against generational or gender lines. Further, we found that the reasons for rodent consumption are multifactorial, including taste preferences, food security, and opportunistic behavior. We argue that on certain topics, such as rodent consumption, establishing trust with communities, and using qualitative research methods, is key to investigate sensitive issues and situate them in their wider context. To conclude, we recommend ways to refine sensitization campaigns to account for these socio-cultural contexts. PMID:26895631

  20. Immunization with Wuchereria bancrofti Glutathione-S-transferase Elicits a Mixed Th1/Th2 Type of Protective Immune Response Against Filarial Infection in Mastomys.

    PubMed

    Andure, Dhananjay; Pote, Kiran; Khatri, Vishal; Amdare, Nitin; Padalkar, Ramchandra; Reddy, Maryada Venkata Rami

    2016-10-01

    Lymphatic filariasis is a mosquito borne parasitic infection and can severely affect the normal working ability of an individual. Currently there is no vaccine available to prevent this infection and the development of a potential vaccine could effectively support the on-going mass drug administration program by World Health Organization (WHO). Filarial parasites have complex mechanisms to modulate the host immune responses against them. The glutathione-S-transferases (GST) are the important enzymes effectively involved to counteract the oxidative free radicals produced by the host. In the present study, we have shown that the mastomys which are fully permissible rodents for Brugia malayi when immunized with Wuchereria bancrofti recombinant GST (rWbGST) could induce 65.5 % in situ cytotoxicity against B. malayi infective (L3) larvae. There was a balanced Th1/Th2 immune response in the vaccinated animals, characterized by higher levels of WbGST-specific IgG1 and IgG2a antibodies and pronounced IFN-γ, IL-10 and IL-4 cytokines production by the spleen cells. PMID:27605739

  1. Elimination of Biomphalaria pfeifferi, Bulinus tropicus and Lymnaea natalensis by the ampullarid snail, Marisa cornuarietis, in a man-made dam in northern Tanzania.

    PubMed

    Nguma, J F; McCullough, F S; Masha, E

    1982-03-01

    Marisa cornuarietis is a well known ampullarid competitor/predator of Biomphalaria glabrata in Puerto Rico. For the first time in Africa a flourishing population of Marisa has been established in a small, permanent, man-made dam at Kisangara, near Moshi, Tanzania. Prior to the release of M. cornuarietis in June 1977, this dam supported thriving populations of the pulmonate snail hosts Biomphalaria pfeifferi and Lymnaea natalensis; Bulinus tropicus and the melaniid Melanoides tuberculata were also common. Some 24 months after the establishment of Marisa the three pulmonate species had been eliminated; only M. tuberculata remained at about the same population density as originally recorded. Marisa has not caused any obvious adverse environmental impact in the dam. There is at present no valid evidence that this ampullarid would be a threat to local rice production, which is the only crop at risk, but carefully designed field trials should be undertaken to confirm or refute this view. In view of the vast number of permanent, lentic habitats throughout the Afrotropical region, which act as important transmission sites of schistosomiasis and fascioliasis, the role of Marisa cornuarietis as a cost-effective biological control agent in integrated control operations deserves henceforth to be energetically explored. PMID:6122367

  2. Sequence Variability and Geographic Distribution of Lassa Virus, Sierra Leone

    PubMed Central

    Stockelman, Michael G.; Moses, Lina M.; Park, Matthew; Stenger, David A.; Ansumana, Rashid; Bausch, Daniel G.; Lin, Baochuan

    2015-01-01

    Lassa virus (LASV) is endemic to parts of West Africa and causes highly fatal hemorrhagic fever. The multimammate rat (Mastomys natalensis) is the only known reservoir of LASV. Most human infections result from zoonotic transmission. The very diverse LASV genome has 4 major lineages associated with different geographic locations. We used reverse transcription PCR and resequencing microarrays to detect LASV in 41 of 214 samples from rodents captured at 8 locations in Sierra Leone. Phylogenetic analysis of partial sequences of nucleoprotein (NP), glycoprotein precursor (GPC), and polymerase (L) genes showed 5 separate clades within lineage IV of LASV in this country. The sequence diversity was higher than previously observed; mean diversity was 7.01% for nucleoprotein gene at the nucleotide level. These results may have major implications for designing diagnostic tests and therapeutic agents for LASV infections in Sierra Leone. PMID:25811712

  3. Lassa Virus Seroprevalence in Sibirilia Commune, Bougouni District, Southern Mali

    PubMed Central

    Sogoba, Nafomon; Rosenke, Kyle; Adjemian, Jennifer; Diawara, Sory Ibrahim; Maiga, Ousmane; Keita, Moussa; Konaté, Drissa; Keita, Abdoul Salam; Sissoko, Ibrahim; Boisen, Matt; Nelson, Diana; Oottamasathien, Darin; Millett, Molly; Garry, Robert F.; Branco, Luis M.; Traoré, Sékou F.; Doumbia, Seydou; Feldmann, Heinz

    2016-01-01

    Lassa virus (LASV) is endemic to several nations in West Africa. In Mali, LASV was unknown until an exported case of Lassa fever was reported in 2009. Since that time, rodent surveys have found evidence of LASV-infected Mastomys natalensis rats in several communities in southern Mali, near the border with Côte d’Ivoire. Despite increased awareness, to date only a single case of Lassa fever has been confirmed in Mali. We conducted a survey to determine the prevalence of LASV exposure among persons in 3 villages in southern Mali where the presence of infected rodents has been documented. LASV IgG seroprevalence ranged from 14.5% to 44% per village. No sex bias was noted; however, seropositivity rates increased with participant age. These findings confirm human LASV exposure in Mali and suggest that LASV infection/Lassa fever is a potential public health concern in southern Mali. PMID:26981786

  4. Poor housing quality increases risk of rodent infestation and Lassa fever in refugee camps of Sierra Leone.

    PubMed

    Bonner, Phillip Cullison; Schmidt, Wolf-Peter; Belmain, Steven R; Oshin, Babafemi; Baglole, Debbie; Borchert, Matthias

    2007-07-01

    Lassa fever, a viral hemorrhagic fever endemic in parts of West Africa, is a severe febrile illness transmitted to humans by the rodent Mastomys natalensis. To determine risk of Lassa fever in households in Sierra Leonean refugee camps, we analyzed the spatial relationships between households with a Lassa case and focal locations of potential rodent habitats. Quality and hygiene factors of households were assessed to determine possible risk factors for household rodent infestation and occurrence of Lassa fever. The odds to have a rat burrow were higher in case houses than in control houses (OR 24, 95% CI 6.0-93). Case houses scored significantly worse in the quality of housing and external hygiene. These findings suggest that risk of Lassa fever in refugee camps depends on individual housing quality and the hygiene of the immediate surrounding environment. PMID:17620650

  5. Observations on the food habits of some African rodents.

    PubMed

    Iwuala, M O; Braide, E I; Maduka, N

    1980-12-01

    Food habits of four common species of African rodents: the giant rat (Cricetomys gambianus), the black house rat (Rattus rattus), the multimammate rat (Mastomys natalensis) and the pygmy mouse (Mus minutoides) were studied on the basis of stomach content analysis, habitat sampling and experimental trials with caged animals. Vegetable items (especially grass, grains and tubers) formed the bulk of the food of all the species. Oil-palm nuts and kernels were also common in the guts of C. gambianus and M. natalensis. Animal food components of all the rodent species comprised mainly insects (especially ants, crickets etc.). Vertebrate flesh and scales were also well represented in the guts of C. gambianus. Domestic and miscellaneous food items were recorded from R. rattus, most of which were trapped in human and animal shelters. Inorganic gut contents, primarily sand grains, were found in sizeable quantities in more than 70% of the rodents examined. Results of experimental feeding trials with caged rodents showed close correlation with those recorded from field samples, especially in terms of food choices and the relative quantities consumed. The ecological and practical implications of these observations are discussed in the light of the importance of the rodents as agricultural and domestic pests. PMID:7323341

  6. μ-Theraphotoxin-An1a: primary structure determination and assessment of the pharmacological activity of a promiscuous anti-insect toxin from the venom of the tarantula Acanthoscurria natalensis (Mygalomorphae, Theraphosidae).

    PubMed

    Rates, Breno; Prates, Maura V; Verano-Braga, Thiago; da Rocha, Angela P; Roepstorff, Peter; Borges, Carlos L; Lapied, Bruno; Murillo, Laurence; Pimenta, Adriano M C; Biondi, Ilka; De Lima, Maria Elena

    2013-08-01

    Tarantulas are included in the mygalomorph spider family Theraphosidae. Although the pharmacological diversity of theraphosid toxins (theraphotoxins) is broad, studies dedicated to the characterization of biologically active molecules from the theraphosid genus Acanthoscurria have been restricted to the investigation of antimicrobial peptides and polyamines produced by the hemocytes of Acanthoscurria gomesiana. The present study reports the purification, primary structure determination and electrophysiological effects of an anti-insect toxin, named μ-theraphotoxin-An1a (μ-TRTX-An1a), from the venom of Acanthoscurria natalensis - a tarantula species occurring in the Brazilian biomes caatinga and cerrado. The analysis of the primary structure of μ-TRTX-An1a revealed the similarity of this toxin to theraphosid toxins bearing a huwentoxin-II-like fold. Electrophysiological experiments showed that μ-TRTX-An1a (100 nM) induces membrane depolarization, increases the spontaneous firing frequency and reduces spike amplitude of cockroach dorsal unpaired median (DUM) neurons. In addition, under voltage-clamp conditions, μ-TRTX-An1a (100 nM) only partially blocks voltage-dependent sodium current amplitudes in DUM neurons without any effect on their voltage dependence. This effect correlates well with the reduction of the spontaneous action potential amplitudes. Altogether, these last results suggest that μ-TRTX-An1a affects insect neuronal voltage-dependent sodium channels, which are among possible channels targeted by this promiscuous toxin. PMID:23651762

  7. The effect of diethylcarbamazine on microfilariae of Litomosoides carinii in vitro and in vivo.

    PubMed

    Weiner, D J; Abraham, D; D'Antonio, R

    1986-01-01

    Culture-derived Litomosoides carinii microfilariae (MFF) were used in in vitro and in vivo systems to investigate the effect of diethylcarbamazine (DEC) on these MFF. In vivo: Male rats, Mastomys natalensis, all of the same age, were injected intrathoracically (12) or intraperitoneally (36) with 10(3) or 10(4) MFF. After 30 min one half of each group of rats was given DEC per os. At 30, 60, and 120 min after DEC administration, two rats from the treated and two from the untreated group were bled and killed. The pleural or peritoneal cavities were rinsed with warm saline (0.15 M NaCl) to recover MFF. In both the intrathoracic and intraperitoneal experiments, equal numbers of MFF were recovered from treated and control rats at 30 and 120 min. However, at 60 min 85.5% fewer were recovered from the treated than from the nontreated animals. MFF were not found in the blood. In vitro: MFF were added to tissue culture dish wells (Linbro Div., Flow Labs, Hamden, Conn) prepared as follows: DEC-Serum (serum from normal rats given DEC at 500 mg/kg), DEC + Serum (serum with added DEC), serum only, RPMI 1640 only, and RPMI 1640 + DEC. Furthermore, the five treatments were prepared either with or without unstimulated peritoneal exudate (PE) cells. At 30 min in the DEC-Serum wells 45% of the MFF had adherent PE cells; in the remaining wells these cells adhered to 11% or fewer MFF. We interpret the aforementioned phenomena as representing the first step in the trapping and elimination of MFF after DEC treatment of L. carinii-infected M. natalensis. PMID:3799010

  8. Viremia and antibody response of small African and laboratory animals to Crimean-Congo hemorrhagic fever virus infection.

    PubMed

    Shepherd, A J; Leman, P A; Swanepoel, R

    1989-05-01

    Eleven species of small African wild mammals, laboratory rabbits, guinea pigs, and Syrian hamsters were infected with Crimean-Congo hemorrhagic fever (CCHF) virus. Low-titered viremia followed by development of antibody was observed in scrub hares (Lepus saxatilis), Cape ground squirrels (Xerus inauris), red veld rats (Aethomys chrysophilus), white tailed rats (Mystromys albicaudatus), bushveld gerbils (Tatera leucogaster), striped mice (Rhabdomys pumilio), and guinea pigs. The maximum viremic titer in 4 scrub hares was 10(1.7-4.2) 50% mouse lethal doses/ml. Viremia was detected in 1/17 infected laboratory rabbits. Antibody response was only detected in South African hedgehogs (Atelerix frontalis), highveld gerbils (T. brantsii), Namaqua gerbils (Desmodillus auricularis), 2 species of multimammate mouse (Mastomys natalensis and M. coucha), and Syrian hamsters. The results of the study indicate that a proportion of infected scrub hares develop CCHF viremia of an intensity shown in the Soviet Union to be sufficient for infection of feeding immature ixodid ticks, but that South African hedgehogs and wild rodents are unlikely to be of importance as maintenance hosts of the virus in southern Africa. PMID:2499205

  9. Stochastic seasonality and nonlinear density-dependent factors regulate population size in an African rodent

    USGS Publications Warehouse

    Leirs, H.; Stenseth, N.C.; Nichols, J.D.; Hines, J.E.; Verhagen, R.; Verheyen, W.

    1997-01-01

    Ecology has long been troubled by the controversy over how populations are regulated. Some ecologists focus on the role of environmental effects, whereas others argue that density-dependent feedback mechanisms are central. The relative importance of both processes is still hotly debated, but clear examples of both processes acting in the same population are rare. Keyfactor analysis (regression of population changes on possible causal factors) and time-series analysis are often used to investigate the presence of density dependence, but such approaches may be biased and provide no information on actual demographic rates. Here we report on both density-dependent and density-independent effects in a murid rodent pest species, the multimammate rat Mastomys natalensis (Smith, 1834), using statistical capture-recapture models. Both effects occur simultaneously, but we also demonstrate that they do not affect all demographic rates in the same way. We have incorporated the obtained estimates of demographic rates in a population dynamics model and show that the observed dynamics are affected by stabilizing nonlinear density-dependent components coupled with strong deterministic and stochastic seasonal components.

  10. Toxoplasmosis seroprevalence in urban rodents: a survey in Niamey, Niger

    PubMed Central

    Mercier, Aurélien; Garba, Madougou; Bonnabau, Henri; Kane, Mamadou; Rossi, Jean-Pierre; Dardé, Marie-Laure; Dobigny, Gauthier

    2013-01-01

    A serological survey of Toxoplasma gondii was conducted on 766 domestic and peridomestic rodents from 46 trapping sites throughout the city of Niamey, Niger. A low seroprevalence was found over the whole town with only 1.96% of the rodents found seropositive. However, differences between species were important, ranging from less than 2% in truly commensal Mastomys natalensis, Rattus rattus and Mus musculus, while garden-associated Arvicanthis niloticus displayed 9.1% of seropositive individuals. This is in line with previous studies on tropical rodents - that we reviewed here - which altogether show that Toxoplasma seroprevalence in rodent is highly variable, depending on many factors such as locality and/or species. Moreover, although we were not able to decipher statistically between habitat or species effect, such a contrast between Nile grass rats and the other rodent species points towards a potentially important role of environmental toxoplasmic infection. This would deserve to be further scrutinised since intra-city irrigated cultures are extending in Niamey, thus potentially increasing Toxoplasma circulation in this yet semi-arid region. As far as we are aware of, our study is one of the rare surveys of its kind performed in Sub-Saharan Africa and the first one ever conducted in the Sahel. PMID:23828008

  11. Housing equity for health equity: a rights-based approach to the control of Lassa fever in post-war Sierra Leone.

    PubMed

    Kelly, J Daniel; Barrie, M Bailor; Ross, Rachel A; Temple, Brian A; Moses, Lina M; Bausch, Daniel G

    2013-01-01

    Poor quality housing is an infringement on the rights of all humans to a standard of living adequate for health. Among the many vulnerabilities of those without adequate shelter is the risk of disease spread by rodents and other pests. One such disease is Lassa fever, an acute and sometimes severe viral hemorrhagic illness endemic in West Africa. Lassa virus is maintained in the rodent Mastomys natalensis, commonly known as the "multimammate rat," which frequently invades the domestic environment, putting humans at risk of Lassa fever. The highest reported incidence of Lassa fever in the world is consistently in the Kenema District of Sierra Leone, a region that was at the center of Sierra Leone's civil war in which tens of thousands of lives were lost and hundreds of thousands of dwellings destroyed. Despite the end of the war in 2002, most of Kenema's population still lives in inadequate housing that puts them at risk of rodent invasion and Lassa fever. Furthermore, despite years of health education and village hygiene campaigns, the incidence of Lassa fever in Kenema District appears to be increasing. We focus on Lassa fever as a matter of human rights, proposing a strategy to improve housing quality, and discuss how housing equity has the potential to improve health equity and ultimately economic productivity in Sierra Leone. The manuscript is designed to spur discussion and action towards provision of housing and prevention of disease in one of the world's most vulnerable populations. PMID:23282054

  12. Rats! Oh No, Not Rats!

    ERIC Educational Resources Information Center

    Strong, Gary E.

    1987-01-01

    Examples of problems encountered in a new library building--including rats and humidity--and a description of the library's collections provide a framework for this presentation of the California State Library's emergency management planning. Current preservation efforts are documented and the library's disaster and security plans are described.…

  13. Plague in Africa from 1935 to 1949

    PubMed Central

    Davis, D. H. S.

    1953-01-01

    The history of plague in Africa during the period 1935-49 is reviewed. Much of the information derives from a questionnaire sent to all African territories in 1950. The annual incidence of plague in Africa declined, particularly from 1946 onwards. In 1949, under 400 cases were reported, as compared with over 6,000 in 1935. By the end of 1949, plague was still active in the Belgian Congo, Kenya and Tanganyika, Madagascar, and southern Africa. No cases were reported from Egypt, Tunisia, Algeria, Morocco, Senegal, or Uganda during 1949. A comparison of the seasonal incidence of plague with prevailing atmospheric conditions (temperature and rainfall) in African territories shows that human plague is more frequent in warm moist weather—60°-80°F (15°-27°C)—than in hot dry, or cold, weather—over 80°F (27°C) or under 60°F (15°C). The highlands of equatorial Africa and of Madagascar appear to provide the optimum environment for the persistence of plague on the domestic (murine) plane and the high-veld and Kalahari of southern Africa on the sylvatic plane. The rat (Rattus rattus) and the multimammate mouse (R. (Mastomys) natalensis) and their fleas Xenopsylla brasiliensis and X. cheopis appear to be mainly responsible for the persistence of the reservoir in the East African highlands; R. rattus and X. cheopis play this role in Madagascar. The gerbils (Tatera and Desmodillus) and their burrow fleas X. philoxera and X. piriei are the main reservoirs of plague in southern Africa. Within these areas, Pasteurella pestis finds an environment suitable for its continued survival; the conditions seem to be comparable to those defined as obtaining in endemic centres in India. Elsewhere in Africa such endemic centres do not appear to exist. PMID:13115987

  14. Housing equity for health equity: a rights-based approach to the control of Lassa fever in post-war Sierra Leone

    PubMed Central

    2013-01-01

    Poor quality housing is an infringement on the rights of all humans to a standard of living adequate for health. Among the many vulnerabilities of those without adequate shelter is the risk of disease spread by rodents and other pests. One such disease is Lassa fever, an acute and sometimes severe viral hemorrhagic illness endemic in West Africa. Lassa virus is maintained in the rodent Mastomys natalensis, commonly known as the “multimammate rat,” which frequently invades the domestic environment, putting humans at risk of Lassa fever. The highest reported incidence of Lassa fever in the world is consistently in the Kenema District of Sierra Leone, a region that was at the center of Sierra Leone’s civil war in which tens of thousands of lives were lost and hundreds of thousands of dwellings destroyed. Despite the end of the war in 2002, most of Kenema’s population still lives in inadequate housing that puts them at risk of rodent invasion and Lassa fever. Furthermore, despite years of health education and village hygiene campaigns, the incidence of Lassa fever in Kenema District appears to be increasing. We focus on Lassa fever as a matter of human rights, proposing a strategy to improve housing quality, and discuss how housing equity has the potential to improve health equity and ultimately economic productivity in Sierra Leone. The manuscript is designed to spur discussion and action towards provision of housing and prevention of disease in one of the world’s most vulnerable populations. PMID:23282054

  15. Understanding and managing sanitary risks due to rodent zoonoses in an African city: beyond the Boston Model.

    PubMed

    Taylor, Peter J; Arntzen, Lorraine; Hayter, Mel; Iles, Malcolm; Frean, John; Belmain, Steven

    2008-03-01

    The Boston Model describes a successful rodent management plan that succeeded in a first-world city in the USA. In third-world cities, which often contain informal shack settlements, it is debatable whether the Boston Model would apply. In Durban, a major harbor city of three million people on the east coast of South Africa, we investigated the sanitary risks due to rodents in both formal (residential and commercial) and informal (shacks) sectors, and we evaluated the relative merits of different management interventions suggested by the Boston Model. Blood and tissue samples of six species (Rattus norvegicus, R. tanezumi, R. rattus, Mus musculus, Mastomys natalensis, Tatera brantsi) from 262 live-trapped rodents from 54 localities were tested for antibodies or DNA for plague (n= 193: antibody test), leptospirosis (n= 221 for antibody test; n= 69 for polymerase chain reaction test for DNA) and toxoplasmosis (n= 217: antibody test). We conducted a socioeconomic survey of 90 household to determine environmental and socioeconomic disease risk factors in the shack settlement of Cato Crest. No rodents were seropositive for plague, but nine Norway rats, R. norvegicus (4.1% of the sample tested) were seropositive for toxoplasmosis, and 22 R. norvegicus (10.0% of sample tested) were seropositive for leptospirosis. Disease endemic areas were concentrated in Cato Crest and the commercial district of Durban. Serology tests of humans living in Cato Crest (n= 219) showed 0% exposure to plague, 23% to leptospirosis and 35% to toxoplasmosis. Compared with shack-dwellers, the residents of brick houses had slightly lower levels of exposure to leptospirosis and toxoplasmosis. Based on our results, environmental hygiene and rodent-trapping campaigns were launched in Cato Crest. The initiative owes much of its current success to implementation of the principles inherent in the Boston Model, even though certain elements were lacking. PMID:21396050

  16. Geographic Distribution and Genetic Characterization of Lassa Virus in Sub-Saharan Mali

    PubMed Central

    Safronetz, David; Sogoba, Nafomon; Lopez, Job E.; Maiga, Ousmane; Dahlstrom, Eric; Zivcec, Marko; Feldmann, Friederike; Haddock, Elaine; Fischer, Robert J.; Anderson, Jennifer M.; Munster, Vincent J.; Branco, Luis; Garry, Robert; Porcella, Stephen F.; Schwan, Tom G.; Feldmann, Heinz

    2013-01-01

    Background Lassa fever is an acute viral illness characterized by multi-organ failure and hemorrhagic manifestations. Lassa fever is most frequently diagnosed in Nigeria, Sierra Leone, Liberia, and Guinea, although sporadic cases have been recorded in other West African countries, including Mali. The etiological agent of Lassa fever is Lassa virus (LASV), an Arenavirus which is maintained in nature and frequently transmitted to humans by Mastomys natalensis. The purpose of this study was to better define the geographic distribution of LASV-infected rodents in sub-Saharan Mali. Methodologies/Principal Findings Small mammals were live-trapped at various locations across Mali for the purpose of identifying potential zoonotic pathogens. Serological and molecular assays were employed and determined LASV infected rodents were exclusively found in the southern Mali near the border of Côte d'Ivoire. Overall, 19.4% of Mastomys natalensis sampled in this region had evidence of LASV infection, with prevalence rates for individual villages ranging from 0 to 52%. Full-length genomic sequences were determined using high throughput sequencing methodologies for LASV isolates generated from tissue samples of rodents collected in four villages and confirmed the phylogenetic clustering of Malian LASV with strain AV. Conclusions/Significance The risk of human infections with LASV is greatest in villages in southern Mali. Lassa fever should be considered in the differential diagnosis for febrile individuals and appropriate diagnostic techniques need to be established to determine the incidence of infection and disease in these regions. PMID:24340119

  17. Rat Bite Fever

    MedlinePlus

    ... Issues Listen Español Text Size Email Print Share Rat Bite Fever Page Content Article Body Rat-bite fever is a disease that occurs in humans who have been bitten by an infected rat or, in some cases, squirrels, mice, cats, and ...

  18. Urban Rat Surveys.

    ERIC Educational Resources Information Center

    Littig, K. S.; And Others

    This guide is for use in the classroom and field training of inspection and operational personnel who serve in planned community rodent-control programs. The urban rat survey may be used as the primary means of obtaining information on rat infestations and the conditions favoring rat populations in urban communities. It provides the data necessary…

  19. Rat-bite fever.

    PubMed

    van Nood, E; Peters, S H A

    2005-09-01

    A 23-year-old woman presented with fever, arthralgias and a skin rash. She possessed nine pet rats, and denied that she had been bitten. Blood culture was positive for Streptobacillus moniliformis, which can cause rat-bite fever. The patient fully recovered after treatment with clarithromycin. PMID:16186643

  20. Prevalence and Risk Factors of Lassa Seropositivity in Inhabitants of the Forest Region of Guinea: A Cross-Sectional Study

    PubMed Central

    Kernéis, Solen; Koivogui, Lamine; Magassouba, N'Faly; Koulemou, Kekoura; Lewis, Rosamund; Aplogan, Aristide; Grais, Rebecca F.; Guerin, Philippe J.; Fichet-Calvet, Elisabeth

    2009-01-01

    Background Lassa fever is a viral hemorrhagic fever endemic in West Africa. The reservoir host of the virus is a multimammate rat, Mastomys natalensis. Prevalence estimates of Lassa virus antibodies in humans vary greatly between studies, and the main modes of transmission of the virus from rodents to humans remain unclear. We aimed to (i) estimate the prevalence of Lassa virus–specific IgG antibodies (LV IgG) in the human population of a rural area of Guinea, and (ii) identify risk factors for positive LV IgG. Methods and Findings A population-based cross-sectional study design was used. In April 2000, all individuals one year of age and older living in three prefectures located in the tropical secondary forest area of Guinea (Gueckedou, Lola and Yomou) were sampled using two-stage cluster sampling. For each individual identified by the sampling procedure and who agreed to participate, a standardized questionnaire was completed to collect data on personal exposure to potential risk factors for Lassa fever (mainly contact with rodents), and a blood sample was tested for LV IgG. A multiple logistic regression model was used to determine risk factors for positive LV IgG. A total of 1424 subjects were interviewed and 977 sera were tested. Prevalence of positive LV Ig was of 12.9% [10.8%–15.0%] and 10.0% [8.1%–11.9%] in rural and urban areas, respectively. Two risk factors of positive LV IgG were identified: to have, in the past twelve months, undergone an injection (odds ratio [OR] = 1.8 [1.1–3.1]), or lived with someone displaying a haemorrhage (OR = 1.7 [1.1–2.9]). No factors related to contacts with rats and/or mice remained statistically significant in the multivariate analysis. Conclusions Our study underlines the potential importance of person-to-person transmission of Lassa fever, via close contact in the same household or nosocomial exposure. PMID:19924222

  1. Rat-bite fever

    MedlinePlus

    Streptobacillary fever; Streptobacillosis; Haverhill fever; Epidemic arthritic erythema; Spirillary fever; Sodoku ... Rat-bite fever can be caused by 2 different bacteria, Streptobacillus moniliformis or Spirillum minus. Both of these are found in ...

  2. What is Desert RATS?

    NASA Video Gallery

    The mission manager and test coordinators for the 2011 mission explain why Desert RATS was started 14 years ago, questions being studied in this year's activities, technologies being tested and the...

  3. Cryptosporidia: epicellular parasites embraced by the host cell membrane.

    PubMed

    Valigurová, Andrea; Jirků, Miloslav; Koudela, Bretislav; Gelnar, Milan; Modrý, David; Slapeta, Jan

    2008-07-01

    The ultrastructure of two gastric cryptosporidia, Cryptosporidium muris from experimentally infected rodents (Mastomys natalensis) and Cryptosporidium sp. 'toad' from naturally infected toads (Duttaphrynus melanostictus), was studied using electron microscopy. Observations presented herein allowed us to map ultrastructural aspects of the cryptosporidian invasion process and the origin of a parasitophorous sac. Invading parasites attach to the host cell, followed by gradual envelopment, with the host's cell membrane folds, eventually forming the parasitophorous sac. Cryptosporidian developmental stages remain epicellular during the entire life cycle. The parasite development is illustrated in detail using high resolution field emission scanning electron microscopy. This provides a new insight into the ultrastructural detail of host-parasite interactions and species-specific differences manifested in frequency of detachment of the parasitophorous sac, radial folds of the parasitophorous sac and stem-formation of the parasitised host cell. PMID:18158154

  4. Diversity and habitat association of small mammals in Aridtsy forest, Awi Zone, Ethiopia

    PubMed Central

    BANTIHUN, Getachew; BEKELE, Afework

    2015-01-01

    Here, we conducted a survey to examine the diversity, distribution and habitat association of small mammals from August 2011 to February 2012 incorporating both wet and dry seasons in Aridtsy forest, Awi Zone, Ethiopia. Using Sherman live traps and snap traps in four randomly selected trapping grids, namely, natural forest, bushland, grassland and farmland, a total of 468 individuals comprising eight species of small mammals (live traps) and 89 rodents of six species (snap traps) were trapped in 2352 and 1200 trap nights, respectively. The trapped small mammals included seven rodents and one insectivore: Lophuromys flavopuntatus (30.6%), Arvicanthis dembeensis (25.8%), Stenocephalemys albipes (20%), Mastomys natalensis (11.6%), Pelomys harringtoni (6.4%), Acomys cahirinus (4.3%), Lemniscomys zebra (0.2%) and the greater red musk shrew (Crocidura flavescens, 1.1%). Analysis showed statistically significant variations in the abundance and habitat preferences of small mammals between habitats during wet and dry seasons. PMID:25855227

  5. Diversity and habitat association of small mammals in Aridtsy forest, Awi Zone, Ethiopia.

    PubMed

    Bantihun, Getachew; Bekele, Afework

    2015-03-18

    Here, we conducted a survey to examine the diversity, distribution and habitat association of small mammals from August 2011 to February 2012 incorporating both wet and dry seasons in Aridtsy forest, Awi Zone, Ethiopia. Using Sherman live traps and snap traps in four randomly selected trapping grids, namely, natural forest, bushland, grassland and farmland, a total of 468 individuals comprising eight species of small mammals (live traps) and 89 rodents of six species (snap traps) were trapped in 2352 and 1200 trap nights, respectively. The trapped small mammals included seven rodents and one insectivore: Lophuromys flavopuntatus (30.6%), Arvicanthis dembeensis (25.8%), Stenocephalemys albipes (20%), Mastomys natalensis (11.6%), Pelomys harringtoni (6.4%), Acomys cahirinus (4.3%), Lemniscomys zebra (0.2%) and the greater red musk shrew (Crocidura flavescens, 1.1%). Analysis showed statistically significant variations in the abundance and habitat preferences of small mammals between habitats during wet and dry seasons. PMID:25855227

  6. Lewis rats have greater response impulsivity than Fischer rats.

    PubMed

    Hamilton, Kristen R; Potenza, Marc N; Grunberg, Neil E

    2014-11-01

    Impulsivity, a tendency toward immediate action without consideration of future consequences, is associated with a wide array of problematic behaviors. Response impulsivity, a type of behaviorally-assessed impulsivity characterized by behavioral disinhibition, is also associated with health risk behaviors. Response impulsivity is distinct from choice impulsivity, which is characterized by intolerance for delay. Lewis rats have higher levels of choice impulsivity than Fischer rats (Anderson & Woolverton, 2005; Madden et al., 2008; Stein et al., 2012). However, no studies have examined whether Lewis and Fischer rats have different levels of response impulsivity. The present research examined response impulsivity in the two rat strains. Subjects were 16 male Lewis and Fischer rats. Rats' response impulsivity was measured using the Five Choice Serial Reaction Time Task (5-CSRTT). In addition, their locomotor activity was measured in locomotor activity chambers. Lewis rats had more premature responses than Fischer rats during the 5-CSRTT assessment [F(1, 14)=5.34, p<0.05], indicating higher levels of response impulsivity. Locomotor activity did not differ between rat strain groups [F(1, 14)=3.05, p=.10], suggesting that overall movement did not account for group differences in response impulsivity on the 5-CSRTT. It can be concluded from this research that Lewis rats have higher levels of response impulsivity than Fischer rats, and therefore provide a valid rat model of individual differences in impulsivity. PMID:24613059

  7. Risk Maps of Lassa Fever in West Africa

    PubMed Central

    Fichet-Calvet, Elisabeth; Rogers, David John

    2009-01-01

    Background Lassa fever is caused by a viral haemorrhagic arenavirus that affects two to three million people in West Africa, causing a mortality of between 5,000 and 10,000 each year. The natural reservoir of Lassa virus is the multi-mammate rat Mastomys natalensis, which lives in houses and surrounding fields. With the aim of gaining more information to control this disease, we here carry out a spatial analysis of Lassa fever data from human cases and infected rodent hosts covering the period 1965–2007. Information on contemporary environmental conditions (temperature, rainfall, vegetation) was derived from NASA Terra MODIS satellite sensor data and other sources and for elevation from the GTOPO30 surface for the region from Senegal to the Congo. All multi-temporal data were analysed using temporal Fourier techniques to generate images of means, amplitudes and phases which were used as the predictor variables in the models. In addition, meteorological rainfall data collected between 1951 and 1989 were used to generate a synoptic rainfall surface for the same region. Methodology/Principal Findings Three different analyses (models) are presented, one superimposing Lassa fever outbreaks on the mean rainfall surface (Model 1) and the other two using non-linear discriminant analytical techniques. Model 2 selected variables in a step-wise inclusive fashion, and Model 3 used an information-theoretic approach in which many different random combinations of 10 variables were fitted to the Lassa fever data. Three combinations of absence∶presence clusters were used in each of Models 2 and 3, the 2 absence∶1 presence cluster combination giving what appeared to be the best result. Model 1 showed that the recorded outbreaks of Lassa fever in human populations occurred in zones receiving between 1,500 and 3,000 mm rainfall annually. Rainfall, and to a much lesser extent temperature variables, were most strongly selected in both Models 2 and 3, and neither vegetation nor

  8. [Fatal rat bites].

    PubMed

    Yanai, O; Goldin, L; Hiss, J

    1999-04-15

    We present a rare case of infant death due to blood loss resulting from multiple rat bites. Domestic dogs and cats cause most animal bites. Bites of a house rat usually cause bacterial infection, successfully treated with antibiotics. There is little information about death due to house rat bites. Since the wounds they cause tend to occur post-mortem, they are usually wedged, clean and without subcutaneous bleeding. An 11-week-old, malnourished infant girl was bitten to death while sleeping in her mother's bed in a rat-infested home. The infant's clothing was covered with blood, parts of her face were missing and marks of gnawing were present on her neck and extremities. There was subcutaneous bleeding around the wounds indicating that they were inflicted while the child was alive. Autopsy findings revealed profound blood loss. We conclude that a combination of low socio-economic status, severe failure to thrive, and poor hygiene in a rat-infested environment contributed to the fatal outcome in this attack. PMID:10955069

  9. Intercepting the first rat ashore.

    PubMed

    Russell, James C; Towns, David R; Anderson, Sandra H; Clout, Mick N

    2005-10-20

    A single Norway rat released on to a rat-free island was not caught for more than four months, despite intensive efforts to trap it. The rat first explored the 9.5-hectare island and then swam 400 metres across open water to another rat-free island, evading capture for 18 weeks until an aggressive combination of detection and trapping methods were deployed simultaneously. The exceptional difficulty of this capture indicates that methods normally used to eradicate rats in dense populations are unlikely to be effective on small numbers, a finding that could have global implications for conservation on protected islands. PMID:16237434

  10. Rat on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken on Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's rock abrasion tool, also known as 'rat' (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  11. Behavior modulation of rats to a robotic rat in multi-rat interaction.

    PubMed

    Shi, Qing; Ishii, Hiroyuki; Tanaka, Katsuaki; Sugahara, Yusuke; Takanishi, Atsuo; Okabayashi, Satoshi; Huang, Qiang; Fukuda, Toshio

    2015-10-01

    In this paper, we study the behavioral response of rats to a robotic rat during multi-rat interaction. Experiments are conducted in an open-field where a robotic rat called WR-5 is put together with three laboratory rats. WR-5 is following one rat (target), while avoiding the other two rats (outside observers) during interaction. The behavioral characteristics of each target rat is evaluated by scoring its locomotor activity and frequencies of performing rearing, body grooming and mounting actions. Additionally, the frequency of being mounted by other rats is also measured. Experimental results show that the target becomes more active after interaction. The rat species, with more active behavioral characteristics, is more susceptible to being adjusted by the robot. The increased time spent by the outside observers in the vicinity of the robot indicates that a biomimetic robot has the promise for modulating rat behavior even without direct interaction. Thus, this study provide a novel approach to shaping the sociality of animals living in groups. PMID:26414400

  12. Landscape determinants of fine-scale genetic structure of a small rodent in a heterogeneous landscape (Hluhluwe-iMfolozi Park, South Africa).

    PubMed

    Russo, Isa-Rita M; Sole, Catherine L; Barbato, Mario; von Bramann, Ullrich; Bruford, Michael W

    2016-01-01

    Small mammals provide ecosystem services, acting, for example, as pollinators and seed dispersers. In addition, they are also disease reservoirs that can be detrimental to human health and they can also act as crop pests. Knowledge of their dispersal preferences is therefore useful for population management and landscape planning. Genetic data were used alongside landscape data to examine the influence of the landscape on the demographic connectedness of the Natal multimammate mouse (Mastomys natalensis) and to identify landscape characteristics that influence the genetic structure of this species across a spatially and temporally varying environment. The most significant landscape features shaping gene flow were aspect, vegetation cover, topographic complexity (TC) and rivers, with western facing slopes, topographic complexity and rivers restricting gene flow. In general, thicket vegetation was correlated with increased gene flow. Identifying features of the landscape that facilitate movement/dispersal in M. natalensis potentially has application for other small mammals in similar ecosystems. As the primary reservoir host of the zoonotic Lassa virus, a landscape genetics approach may have applications in determining areas of high disease risk to humans. Identifying these landscape features may also be important in crop management due to damage by rodent pests. PMID:27406468

  13. [The mammals of Guinea as reservoirs and carriers of arboviruses].

    PubMed

    Konstantinov, O K; Diallo, S M; Inapogi, A P; Ba, A; Kamara, S K

    2006-01-01

    A great body of data on the fauna and ecology of wild mammals and their participation in the circulation of arboviruses were collected when the ecology of the latter of the Republic of Guinea was studied in 1978 to 1989. A hundred and eighteen species belonging to 10 orders were identified. Over 2,000 biological specimens were virologically and serologically examined. Six arboviruses were isolated. These included Dugbe virus (from the hussar monkey Cercopithecus (Erythrocebus patas) and 5 viruses from chiropters: Rift valley fever, from Micropteropus pusillus, Miniopterus schreibersi, and Hipposideros caffer, Saboya, Fomede, and Ank 6909 from Nycteris gambiensis and Kolenter from Hipposideros sp. Fomede, Kolente, and Ank 6909 viruses turned out to be new species for science. Rodents were found to have viral antigens of Lass fever (Mastomys natalensis, Tatera valida kempi and Rattus rattus), Dugbe and Chikungunya fevers (M. natalensis) and West Nile fever (Mus sp.). A serological survey of mammals revealed that the latter had antibodies to 12 arboviruses. Thus, the mammals of Guinea participate in the circulation of 18 arboviruses, 13 of them are pathogenic for man. PMID:16562748

  14. Recent isolations of Lassa virus from Nigerian rodents

    PubMed Central

    Wulff, Herta; Fabiyi, A.; Monath, T. P.

    1975-01-01

    Rodents were trapped in the Benue-Plateau and North-Eastern States of Nigeria where Lassa fever had been reported in previous years. Eight Lassa virus strains were isolated from tissues and blood of rodents identified in the field as being of 3 different species: Mastomys natalensis, Rattus rattus, and Mus minutoides. All the infected rodents were collected in village habitats. These isolations indicate the presence of Lassa virus in wild rodents in Nigeria during periods when no human infections were evident. Prior studies in Sierra Leone have indicated that a single rodent species, M. natalensis, may be the important reservoir host of Lassa virus. Since the present study indicates that other rodent species may be involved as well, the ecology of Lassa virus may be more complicated than was heretofore supposed. In view of the importance of determining the geographic and species range of rodent hosts of Lassa virus, and because of the problems inherent in rodent identification under austere field conditions, it is urgent that further studies be conducted in the same areas of Nigeria to confirm these findings. PMID:1085216

  15. Landscape determinants of fine-scale genetic structure of a small rodent in a heterogeneous landscape (Hluhluwe-iMfolozi Park, South Africa)

    PubMed Central

    Russo, Isa-Rita M.; Sole, Catherine L.; Barbato, Mario; von Bramann, Ullrich; Bruford, Michael W.

    2016-01-01

    Small mammals provide ecosystem services, acting, for example, as pollinators and seed dispersers. In addition, they are also disease reservoirs that can be detrimental to human health and they can also act as crop pests. Knowledge of their dispersal preferences is therefore useful for population management and landscape planning. Genetic data were used alongside landscape data to examine the influence of the landscape on the demographic connectedness of the Natal multimammate mouse (Mastomys natalensis) and to identify landscape characteristics that influence the genetic structure of this species across a spatially and temporally varying environment. The most significant landscape features shaping gene flow were aspect, vegetation cover, topographic complexity (TC) and rivers, with western facing slopes, topographic complexity and rivers restricting gene flow. In general, thicket vegetation was correlated with increased gene flow. Identifying features of the landscape that facilitate movement/dispersal in M. natalensis potentially has application for other small mammals in similar ecosystems. As the primary reservoir host of the zoonotic Lassa virus, a landscape genetics approach may have applications in determining areas of high disease risk to humans. Identifying these landscape features may also be important in crop management due to damage by rodent pests. PMID:27406468

  16. Variable effects of host characteristics on species richness of flea infracommunities in rodents from three continents.

    PubMed

    Kiffner, Christian; Stanko, Michal; Morand, Serge; Khokhlova, Irina S; Shenbrot, Georgy I; Laudisoit, Anne; Leirs, Herwig; Hawlena, Hadas; Krasnov, Boris R

    2014-08-01

    We studied the effect of host gender and body mass on species richness of flea infracommunities in nine rodent host species from three biomes (temperate zone of central Europe, desert of the Middle East and the tropics of East Africa). Using season- and species-specific generalized linear mixed models and controlling for year-to-year variation, spatial clustering of rodent sampling and over-dispersion of the data, we found inconsistent associations between host characteristics and flea species richness. We found strong support for male-biased flea parasitism, especially during the reproductive period (higher species richness in male hosts than in females) in all considered European rodents (Apodemus agrarius, Myodes glareolus and Microtus arvalis) and in one rodent species from the Middle East (Dipodillus dasyurus). In contrast, two of three African rodent species (Lophuromys kilonzoi and Praomys delectorum) demonstrated a trend of female-biased flea species richness. Positive associations between body mass and the number of flea species were detected mainly in males (five of nine species: A. agrarius, M. glareolus, M. arvalis, D. dasyurus and Mastomys natalensis) and not in females (except for M. natalensis). The results of this study support earlier reports that gender-biased, in general, and male-biased, in particular, infestation by ectoparasites is not a universal rule. This suggests that mechanisms of parasite acquisition by an individual host are species-specific and have evolved independently in different rodent host-flea systems. PMID:24820040

  17. Immunocytochemical studies on several developmental stages of Dipetalonema viteae (Filarioidea).

    PubMed

    Prüsse, A; Vollmer, S; Diesfeld, H J

    1983-09-01

    The binding of antibodies to infective larvae (L3), eggs, uterine contents and blood microfilariae was demonstrated by light microscopy employing the peroxidase-antiperoxidase (PAP) method. Antigen-antibody reactions were located on the shell of filarial eggs as well as on the cuticle and the interior of L3 and microfilariae. Using sera from Meriones unguiculatus, Mastomys natalensis and golden hamsters infected with D. viteae obtained at 7, 14, 21 and 28 weeks p.i. it was observed that the intensity of the immunostaining on several developmental stages of the filariae decreased with increasing duration of infection. This effect was more pronounced in the case of M. unguiculatus and M. natalensis than in the case of golden hamsters. For detection of surface antigenicity the simple procedure of drying the test material on microscopic slides proved to be time saving and equally specific as compared to the embedding in Epon of the filarial stages and the successive preparation of semithin sections. However, embedded filarial stages presented more intensive immunostaining than nonembedded stages. Moreover, sections allowed to demonstrate antigen-antibody reactions on the cuticle as well as inside the body cavity of the stages. PMID:6685362

  18. Gravitational Biology: The Rat Model

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In this session, Session JP3, the discussion focuses on the following topics: Morphology of brain, pituitary and thyroid in the rats exposed to altered gravity; Biochemical Properties of B Adrenoceptors After Spaceflight (LMS-STS78) or Hindlimb Suspension in Rats; Influence of Hypergravity on the Development of Monoaminergic Systems in the Rat Spinal Cord; A Vestibular Evoked Potentials (VsEPs) Study of the Function of the Otolith Organs in Different Head Orientations with respect to Earth Gravity Vector in the Rat; Quantitative Observations on the Structure of Selected Proprioceptive Components in Adult Rats that Underwent About Half of their Fetal Development in Space; Effects of a Nine-Day Shuttle Mission on the Development of the Neonatal Rat Nervous System, A Behavioral Study; Muscle Atrophy Associated to Microgravity in Rat, Basic Data For Countermeasures; Simulated Weightlessness by Unloading in the Rat, Results of a Time Course Study of Biochemical Events Occurring During Unloading and Lack of Effect of a rhBNP-2 Treatment on Bone Formation and Bone Mineral Content in Unloading Rats; and Cytological Mechanism of the Osteogenesis Under Microgravity Conditions.

  19. Rat Endovascular Perforation Model

    PubMed Central

    Sehba, Fatima A.

    2014-01-01

    Experimental animal models of aneurysmal subarachnoid hemorrhage (SAH) have provided a wealth of information on the mechanisms of brain injury. The Rat endovascular perforation model (EVP) replicates the early pathophysiology of SAH and hence is frequently used to study early brain injury following SAH. This paper presents a brief review of historical development of the EVP model, details the technique used to create SAH and considerations necessary to overcome technical challenges. PMID:25213427

  20. Sugar bingeing in rats.

    PubMed

    Avena, Nicole M; Rada, Pedro; Hoebel, Bartley G

    2006-08-01

    Bingeing behavior is characteristic of many eating disorders. This unit describes an animal model of sugar bingeing. This model has been used successfully to elicit behavioral and neurochemical signs of sugar dependence in rats, e.g., indices of bingeing, withdrawal, increased intake after abstinence (deprivation effect), cross-sensitization with amphetamine, and increases in dopamine release in the nucleus accumbens due to repeated bingeing. PMID:18428651

  1. Laughing rats are optimistic.

    PubMed

    Rygula, Rafal; Pluta, Helena; Popik, Piotr

    2012-01-01

    Emotions can bias human decisions- for example depressed or anxious people tend to make pessimistic judgements while those in positive affective states are often more optimistic. Several studies have reported that affect contingent judgement biases can also be produced in animals. The animals, however, cannot self-report; therefore, the valence of their emotions, to date, could only be assumed. Here we present the results of an experiment where the affect-contingent judgement bias has been produced by objectively measured positive emotions. We trained rats in operant Skinner boxes to press one lever in response to one tone to receive a food reward and to press another lever in response to a different tone to avoid punishment by electric foot shock. After attaining a stable level of discrimination performance, the animals were subjected to either handling or playful, experimenter-administered manual stimulation - tickling. This procedure has been confirmed to induce a positive affective state in rats, and the 50-kHz ultrasonic vocalisations (rat laughter) emitted by animals in response to tickling have been postulated to index positive emotions akin to human joy. During the tickling and handling sessions, the numbers of emitted high-frequency 50-kHz calls were scored. Immediately after tickling or handling, the animals were tested for their responses to a tone of intermediate frequency, and the pattern of their responses to this ambiguous cue was taken as an indicator of the animals' optimism. Our findings indicate that tickling induced positive emotions which are directly indexed in rats by laughter, can make animals more optimistic. We demonstrate for the first time a link between the directly measured positive affective state and decision making under uncertainty in an animal model. We also introduce innovative tandem-approach for studying emotional-cognitive interplay in animals, which may be of great value for understanding the emotional-cognitive changes

  2. Sex-biased parasitism is not universal: evidence from rodent-flea associations from three biomes.

    PubMed

    Kiffner, Christian; Stanko, Michal; Morand, Serge; Khokhlova, Irina S; Shenbrot, Georgy I; Laudisoit, Anne; Leirs, Herwig; Hawlena, Hadas; Krasnov, Boris R

    2013-11-01

    The distribution of parasites among individual hosts is characterised by high variability that is believed to be a result of variations in host traits. To find general patterns of host traits affecting parasite abundance, we studied flea infestation of nine rodent species from three different biomes (temperate zone of central Europe, desert of Middle East and tropics of East Africa). We tested for independent and interactive effects of host sex and body mass on the number of fleas harboured by an individual host while accounting for spatial clustering of host and parasite sampling and temporal variation. We found no consistent patterns of the effect of host sex and body mass on flea abundance either among species within a biome or among biomes. We found evidence for sex-biased flea infestation in just five host species (Apodemus agrarius, Myodes glareolus, Microtus arvalis, Gerbillus andersoni, Mastomys natalensis). In six rodent species, we found an effect of body mass on flea abundance (all species mentioned above and Meriones crassus). This effect was positive in five species and negative in one species (Microtus arvalis). In M. glareolus, G. andersoni, M. natalensis, and M. arvalis, the relationship between body mass and flea abundance was mediated by host sex. This was manifested in steeper change in flea abundance with increasing body mass in male than female individuals (M. glareolus, G. andersoni, M. natalensis), whereas the opposite pattern was found in M. arvalis. Our findings suggest that sex and body mass are common determinants of parasite infestation in mammalian hosts, but neither of them follows universal rules. This implies that the effect of host individual characteristics on mechanisms responsible for flea acquisition may be manifested differently in different host species. PMID:23636459

  3. Infectious sialodacryoadenitis and rat breeding.

    PubMed

    Utsumi, K; Ishikawa, T; Maeda, T; Shimizu, S; Tatsumi, H; Fujiwara, K

    1980-10-01

    The littering rate of female rats was significantly lowered when they had been exposed to sialodacryoadenitis early in pregnancy. Rats of 8 weeks or more of age were highly susceptible to contact infection, showing marked decrease in bodyweight gain, whereas those of 5-6 weeks of age were resistant. PMID:7464018

  4. War on Rats, 1972 Progress Report.

    ERIC Educational Resources Information Center

    District of Columbia Dept. of Environmental Services, Washington, DC.

    The City of Washington, D.C., with federal funding, declared war on one of the city's most pressing problems--rats. The War on Rats Program, in conjunction with Operation Clean Sweep, made a city-wide survey of rat infestations and recorded the areas of heavy rat infestation. After the problem areas had been identified, community organizations…

  5. Electroejaculation of chimeric rats

    PubMed Central

    McCoy, Marina R.; Montonye, Daniel; Bryda, Elizabeth C.

    2014-01-01

    With the advent of genetic engineering of rodents came the need to assess fertility and germline competency, especially in chimeric rodents generated using embryonic stem cells. Traditional methods rely on natural mating and progeny testing, which is time- and cost-intensive. Electroejaculation is a faster method of collecting sperm for genetic analysis and offers the additional benefit of using fewer animals. This column describes a refined electroejaculation technique for chimeric rats using light gas anesthesia and a custom-made platform for sperm collection. PMID:23689457

  6. Electroejaculation of chimeric rats.

    PubMed

    McCoy, Marina R; Montonye, Daniel; Bryda, Elizabeth C

    2013-06-01

    With the advent of genetic engineering of rodents came the need to assess fertility and germline competency, especially in chimeric rodents generated using embryonic stem cells. Traditional methods rely on natural mating and progeny testing, which is time- and cost-intensive. Electroejaculation is a faster method of collecting sperm for genetic analysis and offers the additional benefit of using fewer animals. This column describes a refined electroejaculation technique for chimeric rats using light gas anesthesia and a custom-made platform for sperm collection. PMID:23689457

  7. Generation of Hprt-disrupted rat through mouse←rat ES chimeras

    PubMed Central

    Isotani, Ayako; Yamagata, Kazuo; Okabe, Masaru; Ikawa, Masahito

    2016-01-01

    We established rat embryonic stem (ES) cell lines from a double transgenic rat line which harbours CAG-GFP for ubiquitous expression of GFP in somatic cells and Acr3-EGFP for expression in sperm (green body and green sperm: GBGS rat). By injecting the GBGS rat ES cells into mouse blastocysts and transplanting them into pseudopregnant mice, rat spermatozoa were produced in mouse←rat ES chimeras. Rat spermatozoa from the chimeric testis were able to fertilize eggs by testicular sperm extraction combined with intracytoplasmic sperm injection (TESE-ICSI). In the present paper, we disrupted rat hypoxanthine-guanine phosphoribosyl transferase (Hprt) gene in ES cells and produced a Hprt-disrupted rat line using the mouse←rat ES chimera system. The mouse←rat ES chimera system demonstrated the dual advantages of space conservation and a clear indication of germ line transmission in knockout rat production. PMID:27062982

  8. Generation of Hprt-disrupted rat through mouse←rat ES chimeras.

    PubMed

    Isotani, Ayako; Yamagata, Kazuo; Okabe, Masaru; Ikawa, Masahito

    2016-01-01

    We established rat embryonic stem (ES) cell lines from a double transgenic rat line which harbours CAG-GFP for ubiquitous expression of GFP in somatic cells and Acr3-EGFP for expression in sperm (green body and green sperm: GBGS rat). By injecting the GBGS rat ES cells into mouse blastocysts and transplanting them into pseudopregnant mice, rat spermatozoa were produced in mouse←rat ES chimeras. Rat spermatozoa from the chimeric testis were able to fertilize eggs by testicular sperm extraction combined with intracytoplasmic sperm injection (TESE-ICSI). In the present paper, we disrupted rat hypoxanthine-guanine phosphoribosyl transferase (Hprt) gene in ES cells and produced a Hprt-disrupted rat line using the mouse←rat ES chimera system. The mouse←rat ES chimera system demonstrated the dual advantages of space conservation and a clear indication of germ line transmission in knockout rat production. PMID:27062982

  9. Male rat sexual behavior.

    PubMed

    Agmo, A

    1997-05-01

    The male rat's sexual behavior constitutes a highly ordered sequence of motor acts involving both striate and smooth muscles. It is spontaneously displayed by most adult made rats in the presence of a sexually receptive female. Although the behavior is important for the survival of the species it is not necessary for survival of the individual. In that way it is different from other spontaneous behaviors such as eating, drinking, avoidance of pain, respiration or thermoregulation. Among other things, this means that it is difficult to talk about sexual deprivation or need. Nevertheless, studies of male sex behavior distinguish sexual motivation (the ease by which behavior is activated, "libido") from the execution of copulatory acts (performance, "potency") (Meisel, R.L. and Sachs, B.D., The physiology of male sexual behavior. In: E. Knobil and J.D. Neill (Eds.), The Physiology of Reproduction, 2nd Edn., Vol. 2, Raven Press, New York, 1994, pp. 3-105 [13]). The hormonal control of male sexual behavior has been extensively studied. It is clear that steroid hormones, androgens and estrogens, act within the central nervous system, modifying neuronal excitability. The exact mechanism by which these hormones activate sex behavior remains largely unknown. However, there exists a considerable amount of knowledge concerning the brain structures important for sexual motivation and for the execution of sex behavior. The modulatory role of some non-steroid hormones is partly known, as well as the consequences of manipulations of several neurotransmitter systems. PMID:9385085

  10. Postural development in rats.

    PubMed

    Lelard, T; Jamon, M; Gasc, J-P; Vidal, P-P

    2006-11-01

    Mammals adopt a limited number of postures during their day-to-day activities. These stereotyped skeletal configurations are functionally adequate and limit the number of degrees of freedom to be controlled by the central nervous system. The temporal pattern of emergence of these configurations in altricial mammals is unknown. We therefore carried out an X-ray study in unrestrained rats from birth (P0) until postnatal day 23 (P23). The X-rays showed that many of the skeletal configurations described in adult rodents were already present at birth. By contrast, limb placement changed abruptly at around P10. These skeletal configurations, observed in anesthetized pups, required the maintenance of precise motor control. On the other hand, motor control continued to mature, as shown by progressive changes in resting posture and head movements from P0 to P23. We suggest that a few innate skeletal configurations provide the necessary frames of reference for the gradual construction of an adult motor repertoire in altricial mammals, such as the rat. The apparent absence of a requirement for external sensorial cues in the maturation of this repertoire may account for the maturation of postural and motor control in utero in precocial mammals (Muir et al., 2000 for a review on the locomotor behavior of altricial and precocial animals). PMID:16814770

  11. Stress-reactive rats (high-avoidance female rats) have a shorter lifespan than stress-nonreactive rats (low-avoidance female rats)

    PubMed Central

    Ohta, Ryo; Kumagai, Fumiaki; Marumo, Hideki; Usumi, Kenji; Saito, Yoshiaki; Kuwagata, Makiko

    2015-01-01

    Although Hatano high-avoidance and low-avoidance rats (HAA and LAA, respectively) have been selectively bred for good versus poor avoidance learning, HAA rats are known to be more reactive to stress than LAA rats. In this study, HAA and LAA female rats were compared during reproductive aging by observing estrous cycles from 8 to 11 months of age. Furthermore, these rats were allowed to live out their natural lifespans, that is, until 24 months of age, in order to compare their survival and to clarify the relationship between reproductive aging and tumor development. At eight months of age, 2 of 35 HAA rats and 20 of 35 LAA rats had abnormal estrous cycles. The median lifespan of the HAA rats (673 days) was shorter than that of the LAA rats (733 days). The incidence of pituitary neoplasia was higher in the HAA rats than in the LAA rats. These results suggest that HAA female rats (i.e., stress-reactive rats) have a shorter lifespan than LAA female rats (i.e., stress-nonreactive rats) and develop pituitary neoplasia, which was one of the causal factors in their accelerated mortality. However, the onset of an age-matched abnormal cycle did not correspond with their lifespan. PMID:27182111

  12. Hormonal changes in antiorthostatic rats

    NASA Technical Reports Server (NTRS)

    Popovic, V.; Popovic, P.; Honeycutt, C.

    1982-01-01

    Hypokinesia, especially hypokinesia with negative tilt ('antiorthostatic hypokinesia'), mimics some of the effects of weightlessness. It is shown that cardiac output is increased during early exposure of rats to antiorthostatic hypokinesia. The increase of the stroke volume and of the cardiac output observed in the antiorthostatic hypokinetic rats is probably the consequence of a blood volume shift toward the chest brought forth by head-down positioning of the animals. It is also possible that struggling of the animals to escape from the harness and an increased metabolism contribute to the elevation of cardiac output. In order to study this hypothesis 'stress hormones' were measured in the antiorthostatic rats. Plasma levels of ACTH, corticosterone and prolactin were measured in the arterial blood (0.3 ml) sampled before, during and after hypokinesia from chronic aortic cannulas of the rats.

  13. Autoshaping in micrencephalic rats

    SciTech Connect

    Goldstein, L.H.; Oakley, D.A.

    1989-06-01

    An autoshaping procedure in which the illumination of a lever was predictive of food reinforcement was used to compare learning in rats with micrencephaly induced by irradiation on the 16th day of gestation and in sham-irradiated controls. Both groups showed equivalent levels of lever-directed activity, and the micrencephalic animals differentiated as well as the control animals between the predictive lever and a nonpredictive lever. The micrencephalic animals were able to redistribute their lever-directed activity when the significance of the levers was reversed and did so more readily than the control animals. Results support the claim that association learning survives either traumatic or developmental neocortical damage and have implications for remedial procedures following both head injury and developmental cerebral pathology in humans.

  14. Rat liver imidase.

    PubMed

    Yang, Y S; Ramaswamy, S; Jakoby, W B

    1993-05-25

    Imidase, an enzyme variously identified as dihydropyrimidinase (EC 3.5.2.2), hydantoinase, dihydropyrimidine hydrase, and dihydropyrimidine amidohydrolase, has been purified to electrophoretic homogeneity from rat liver. Although a component in the chain of pyrimidine catabolism, imidase is capable of serving in a broader role that includes detoxication of xenobiotics. The enzyme catalyzes the hydrolytic cleavage of imides that range from the linear to the heterocyclic and that include hydantoins, dihydropyrimidines, and phthalimide. For some substrates, the reaction is experimentally reversible. The pH activity curves are a function of the pKa of the individual substrate's imino group, with cleavage favored at a pH near the respective pKa value. There is evidence for stereoselectivity and for stereospecificity. A mechanism is proposed for the enzyme-catalyzed reaction. PMID:8388376

  15. EXPERIMENTAL PARACOCCIDIOIDOMYCOSIS IN PREGNANT RATS

    PubMed Central

    LOTH, Eduardo Alexandre; CECATTO, Vanessa; BIAZIM, Samia Khalil; FERREIRA, José Henrique Fermino; DANIELLI, Caroline; GENSKE, Rodrigo Daniel; GANDRA, Rinaldo Ferreira; de FRANCO, Marcello Fabiano

    2015-01-01

    Paracoccidioidomycosis (PCM), caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb), is the most prevalent systemic mycosis in Latin America. There are few reports in the literature about the disease damages during pregnancy and the consequences to the fetuses and breeding. This study evaluated the implications of PCM during pregnancy on offspring and mothers in Wistar rats. Groups of rats were submitted to systemic Pb infection, by intraperitoneal infusion, and mated 30 days after the infection date. Immediately after birth, rats and neonates were sacrificed to obtain organs for standard histological examination, morphometric analysis, fungi recovery by plating (CFU) and dosing of anti-Pb antibodies by ELISA. There were no stillbirths or miscarriages, however, the fetuses from infected pregnant rats had lower body and organ weight but the fertility rate was 100%. The largest number of CFU was recovered from the organ of pregnant rats, the pathological examination revealed more severe infection in the same group, further on the largest number of granulomas and fungal field. It can be concluded that the PCM was more severe in the group of pregnant rats, with implications to the weight of offspring. PMID:27049707

  16. Sevoflurane-induced pica in female rats.

    PubMed

    Yamamoto, Kouichi; Yamamoto, Emiri; Sugimoto, Toru; Sagakami, Takuya; Yamatodani, Atsushi

    2016-05-01

    We examined the effects of volatile anesthetics on pica, which can be used to assess nausea and vomiting in rats. We found that inhalation anesthesia with sevoflurane significantly induced pica in female but not male rats. Among the female rats, young rats (8 weeks old) were more susceptible to its induction than adult rats (20 weeks old) with ovariectomy or sham-surgery. Anti-emetic drugs that are used to prevent postoperative nausea and vomiting (PONV) inhibited the pica. These results suggest that sevoflurane-induced pica in young female rats has the potential to be an animal model of PONV in humans. PMID:27156008

  17. False Context Fear Memory in Rats

    ERIC Educational Resources Information Center

    Bae, Sarah; Holmes, Nathan M.; Westbrook, R. Frederick

    2015-01-01

    Four experiments used rats to study false context fear memories. In Experiment 1, rats were pre-exposed to a distinctive chamber (context A) or to a control environment (context C), shocked after a delay in a second chamber (context B) and tested either in B or A. Rats pre-exposed to A froze just as much as control rats in B but more than control…

  18. Tuberculosis Detection by Giant African Pouched Rats

    ERIC Educational Resources Information Center

    Poling, Alan; Weetjens, Bart; Cox, Christophe; Beyene, Negussie; Durgin, Amy; Mahoney, Amanda

    2011-01-01

    In recent years, operant discrimination training procedures have been used to teach giant African pouched rats to detect tuberculosis (TB) in human sputum samples. This article summarizes how the rats are trained and used operationally, as well as their performance in studies published to date. Available data suggest that pouched rats, which can…

  19. Hematopoiesis in antiorthostatic, hypokinesic rats

    NASA Technical Reports Server (NTRS)

    Dunn, C. D. R.; Johnson, P. C.; Lange, R. D.

    1983-01-01

    Rats exposed to antiorthostatic, hypokinesia showed the following effects which are comparable to those seen in man during or after space flight: weight loss, reduced food and water consumption, transient increases in peripheral hematocrit and RBC count, decreasing MCV and reduced reticulocyte count. In addition, the hemoglobin P50 was shifted to the right. A significant shortening of RBC t1/2 was only seen after suspension. Changes in leukocyte and platelet numbers in suspended rats were also comparable to those in man during space flight, but leukocyte PHA sensitivity in rats showed no consistent alteration. The results demonstrate that this model reproduces many of the hematological effects of space flight and has potential as a tool in understanding the hematopoietic response to zero gravity.

  20. Rats are sensitive to ambiguity.

    PubMed

    Fast, Cynthia D; Blaisdell, Aaron P

    2011-12-01

    In the present study, we investigated response decisions made under conditions of incomplete information in rats. In Experiment 1, rats were trained on either a positive patterning (PP; A-, B-, AB+) or a negative patterning (NP; A+, B+, AB-) instrumental lever-press discrimination. Subjects that had learned an NP discrimination responded less to Cue A when Cue B was covered at test. The cover did not, however, affect test responses to Cue A in the PP condition. In Experiment 2, rats received concurrent training on both PP and NP discriminations. After concurrent training, responses to Cue A were different with B covered versus uncovered for both NP and PP discriminations. We discuss possible accounts for why exposure to a nonlinearly soluble discrimination (NP) may have affected sensitivity to cue ambiguity produced by the cover. These results have interesting implications for representational processes engaged in problem solving. PMID:21968926

  1. Swimming-based pica in rats.

    PubMed

    Nakajima, Sadahiko

    2016-09-01

    We have recently demonstrated that voluntary or forced running in activity wheels yields pica behavior (kaolin clay intake) in rats (Nakajima, 2016; Nakajima and Katayama, 2014). The present study provides experimental evidence that a single 40-min session of swimming in water also generates pica in rats, while showering rats with water does not produce such behavior. Because kaolin intake has been regarded as a measure of nausea in rats, this finding suggests that swimming activity, as well as voluntary or forced running, induces nausea in rats. PMID:27370361

  2. Struvite Urolithiasis in Long–Evans Rats

    PubMed Central

    Pang, Jassia; Borjeson, Tiffany M; Parry, Nicola MA; Fox, James G

    2015-01-01

    Struvite urinary calculi, which are composed of magnesium, ammonium, and phosphate, can cause complications including sepsis and renal failure. Struvite calculi were identified within the urinary bladder and renal pelvis of 2 Long-Evans rats that died within days after arrival from a commercial vendor. The remaining rats in the shipment were screened by physical examination, radiography, and ultrasonography, revealing an additional 2 animals that were clinically affected. These rats were euthanized, necropsied, and yielded similar findings to those from the first 2 rats. In addition, urine samples had an alkaline pH and contained numerous bacteria (predominantly Proteus mirabilis), leukocytes, and crystals. All calculi were composed completely of struvite. Another 7 rats in the shipment had alkaline urine with the presence of blood cells; 6 of these rats also had abundant struvite crystals, and P. mirabilis was cultured from the urine of 3 rats. Further investigation by the vendor identified 2 of 100 rats with struvite calculi from the same colony. Although no specific cause could be implicated, the fact that all the affected rats came from the same breeding area suggests a genetic or environmental triggering event; a contribution due to diet cannot be ruled out. Our findings suggest that the affected rats had metabolic disturbances coupled with bacterial infection that predisposed them to develop struvite calculi. During sudden increases of struvite urinary calculi cases in rats, urine cultures followed by appropriate surgical intervention and antibiotic therapy is warranted. Additional factors, including diet, merit attention as well. PMID:26678365

  3. Gender differences in ondansetron pharmacokinetics in rats.

    PubMed

    Yang, Si H; Yang, Kyung H; Lee, Myung G

    2008-10-01

    It has been reported that ondansetron is primarily metabolized via hepatic CYP2D and 3A1/2 in male Sprague-Dawley rats, and CYP2D1 and 3A2 are male dominant and male specific isozymes, respectively, in rats. Thus, it could be expected that the pharmacokinetics of ondansetron would be changed in male rats compared with those in female rats. Thus, gender-different ondansetron pharmacokinetics were evaluated after its intravenous or oral administration at a dose of 8 mg/kg to male and female Sprague-Dawley rats. After intravenous administration of ondansetron to male rats, the AUC and time-averaged non-renal clearance (Clnr) of the drug were significantly smaller (22.6% decrease) and faster (27.3% increase), respectively, than those in female rats. This probably could be due to faster hepatic blood flow rate in male rats. After oral administration of ondansetron to male rats, the AUC of the drug was also significantly smaller (58.8% decrease) than that in female rats, and this could have been due mainly to increased intestinal metabolism of ondansetron in addition to increased hepatic metabolism of the drug in male rats. PMID:18696412

  4. Gene expression in rat brain.

    PubMed

    Milner, R J; Sutcliffe, J G

    1983-08-25

    191 randomly selected cDNA clones prepared from rat brain cytoplasmic poly (A)+ RNA were screened by Northern blot hybridization to rat brain, liver and kidney RNA to determine the tissue distribution, abundance and size of the corresponding brain mRNA. 18% hybridized to mRNAs each present equally in the three tissues, 26% to mRNAs differentially expressed in the tissues, and 30% to mRNAs present only in the brain. An additional 26% of the clones failed to detect mRNA in the three tissues at an abundance level of about 0.01%, but did contain rat cDNA as demonstrated by Southern blotting; this class probably represents rare mRNAs expressed in only some brain cells. Therefore, most mRNA expressed in brain is either specific to brain or otherwise displays regulation. Rarer mRNA species tend to be larger than the more abundant species, and tend to be brain specific; the rarest, specific mRNAs average 5000 nucleotides in length. Ten percent of the clones hybridize to multiple mRNAs, some of which are expressed from small multigenic families. From these data we estimate that there are probably at most 30,000 distinct mRNA species expressed in the rat brain, the majority of which are uniquely expressed in the brain. PMID:6193485

  5. Ontogeny of rat hepatic adrenoceptors

    SciTech Connect

    McMillian, M.K.; Schanberg, S.M.; Kuhn, C.M.

    1983-10-01

    Hepatic alpha-1, alpha-2 and beta-2 adrenoceptors were characterized during development of the rat through Scatchard analysis of (3H)prazosin, (3H)rauwolscine and (125I)pindolol binding to liver membrane preparations. Major changes in adrenoceptor numbers occur shortly before birth at weaning. The fetal rat liver is characterized by a large number of alpha-2 adrenoceptors, which falls 10-fold by birth. The number of hepatic beta-2 adrenoceptors decreases gradually during development, and is lower at all times than the number of alpha-1 and alpha-2 adrenoceptors. The developmental profile of the hepatic alpha-1 adrenoceptor is biphasic: there is a 2 to 3-fold fall in alpha-1 adrenoceptor number at birth and a 3- to 5-fold rise at weaning. While absolute numbers of alpha-1 and beta-2 adrenoceptors do not correlate precisely with reported actions of epinephrine and norepinephrine on hepatic metabolism during ontogeny, the increasing ratio of alpha-1/beta-2 hepatic adrenoceptors may contribute to the conversion from predominantly beta effects of catecholamines reported in fetal and suckling rat liver to the predominantly alpha-1 effects that are well documented in the adult male rat.

  6. Whiskers aid anemotaxis in rats.

    PubMed

    Yu, Yan S W; Graff, Matthew M; Bresee, Chris S; Man, Yan B; Hartmann, Mitra J Z

    2016-08-01

    Observation of terrestrial mammals suggests that they can follow the wind (anemotaxis), but the sensory cues underlying this ability have not been studied. We identify a significant contribution to anemotaxis mediated by whiskers (vibrissae), a modality previously studied only in the context of direct tactile contact. Five rats trained on a five-alternative forced-choice airflow localization task exhibited significant performance decrements after vibrissal removal. In contrast, vibrissal removal did not disrupt the performance of control animals trained to localize a light source. The performance decrement of individual rats was related to their airspeed threshold for successful localization: animals that found the task more challenging relied more on the vibrissae for localization cues. Following vibrissal removal, the rats deviated more from the straight-line path to the air source, choosing sources farther from the correct location. Our results indicate that rats can perform anemotaxis and that whiskers greatly facilitate this ability. Because air currents carry information about both odor content and location, these findings are discussed in terms of the adaptive significance of the interaction between sniffing and whisking in rodents. PMID:27574705

  7. TUMOR PROMOTION IN RAT LIVER

    EPA Science Inventory

    An initiation promotion bioassay for chemical carcinogens and tumor promoters has been developed in rat liver using presumed preneoplastic lesions, foci of gamma-glutamyltranspeptidase (GGTase)-positive hepatocytes, as the endpoint. To evaluate the tumor-promoting activity of phe...

  8. Rat spermatogenesis in mouse testis

    PubMed Central

    Clouthier, David E.; Avarbock, Mary R.; Maika, Shanna D.; Hammer, Robert E.

    2016-01-01

    Recently, transplantation of mouse donor spermatogonial stem cells from a fertile testis to an infertile recipient mouse testis was described1,2. The donor cells established spermatogenesis in the seminiferous tubules of the host, and normal spermatozoa were produced. In the most successful transplants, the recipient mice were fertile and sired up to 80 per cent of progeny from donor cells2. Here we examine the feasibility of transplanting spermatogonial stem cells from other species to the mouse seminiferous tubule to generate spermatogenesis. Marked testis cells from transgenic rats were transplanted to the testes of immunodeficient mice, and in all of 10 recipient mice (in 19 of 20 testes), rat spermatogenesis occurred. Epididymides of eight mice were examined, and the three from mice with the longest transplants (≥110 days) contained rat spermatozoa with normal morphology. The generation of rat spermatogenesis in mouse testes suggests that spermatogonial stem cells of many species could be transplanted, and opens the possibility of xenogeneic spermatogenesis for other species. PMID:8632797

  9. Whiskers aid anemotaxis in rats

    PubMed Central

    Yu, Yan S. W.; Graff, Matthew M.; Bresee, Chris S.; Man, Yan B.; Hartmann, Mitra J. Z.

    2016-01-01

    Observation of terrestrial mammals suggests that they can follow the wind (anemotaxis), but the sensory cues underlying this ability have not been studied. We identify a significant contribution to anemotaxis mediated by whiskers (vibrissae), a modality previously studied only in the context of direct tactile contact. Five rats trained on a five-alternative forced-choice airflow localization task exhibited significant performance decrements after vibrissal removal. In contrast, vibrissal removal did not disrupt the performance of control animals trained to localize a light source. The performance decrement of individual rats was related to their airspeed threshold for successful localization: animals that found the task more challenging relied more on the vibrissae for localization cues. Following vibrissal removal, the rats deviated more from the straight-line path to the air source, choosing sources farther from the correct location. Our results indicate that rats can perform anemotaxis and that whiskers greatly facilitate this ability. Because air currents carry information about both odor content and location, these findings are discussed in terms of the adaptive significance of the interaction between sniffing and whisking in rodents. PMID:27574705

  10. Transgenic hepatocarcinogenesis in the rat.

    PubMed Central

    Hully, J. R.; Su, Y.; Lohse, J. K.; Griep, A. E.; Sattler, C. A.; Haas, M. J.; Dragan, Y.; Peterson, J.; Neveu, M.; Pitot, H. C.

    1994-01-01

    Although transgenic hepatocarcinogenesis has been accomplished in the mouse with a number of genetic constructs targeting the oncogene to expression primarily in the liver, no example of this process has yet been developed in the rat. Because our understanding of the multistage nature of hepatocarcinogenesis is most advanced in the rat, we have developed a strain of transgenic rats carrying the promoter-enhancer sequences of the mouse albumin gene linked 5' to the simian virus-40 T antigen gene. A line of transgenic rats bearing this transgene has been developed from a single founder female. Five to six copies of the transgene, possibly in tandem, occur within the genome of the transgenic animals, which are maintained by heterozygous matings. Livers of transgenic animals are histologically normal after weaning; at 2 months of age, small foci of vacuolated cells appear in this organ. By 4 months of age, all animals exhibit focal lesions and nodules consisting primarily of small basophilic cells, many of which exhibit considerable cytoplasmic vacuolization. Mating of animals each bearing the transgene results in rats with a demyelinating condition that develops acutely in pregnant females and more chronically in males. Ultrastructural studies of these cells indicate that the vacuoles contain substantial amounts of glycogen, with the cells resembling hepatoblasts. Malignant neoplasms with both a glandular and a hepatoblastoma/hepatocellular carcinoma pattern arise from the nodules. Enzyme and immunohistochemical studies of all lesions reveal many similarities in gene expression to comparable lesions in rats subjected to chemically induced hepatocarcinogenesis, with certain exceptions. The placental form of glutathione-S-transferase is absent from all lesions in the transgenic animal, as is the expression of connexin 32. A significant number of lesions express serum albumin, and many, but not all, exhibit the T antigen. Lesions expressing the T antigen also contain

  11. Early life stress induces renal dysfunction in adult male rats but not female rats

    PubMed Central

    Loria, Analia S.; Yamamoto, Tatsuo; Pollock, Jennifer S.

    2013-01-01

    Maternal separation (MatSep) is a model of behavioral stress during early life. We reported that MatSep exacerbates ANG II-induced hypertension in adult male rats. The aims of this study were to determine whether exposure to MatSep in female rats sensitizes blood pressure to ANG II infusion similar to male MatSep rats and to elucidate renal mechanisms involved in the response in MatSep rats. Wistar Kyoto (WKY) pups were exposed to MatSep 3 h/day from days 2 to 14, while control rats remained with their mothers. ANG II-induced mean arterial pressure (MAP; telemetry) was enhanced in female MatSep rats compared with control female rats but delayed compared with male MatSep rats. Creatinine clearance (Ccr) was reduced in male MatSep rats compared with control rats at baseline and after ANG II infusion. ANG II infusion significantly increased T cells in the renal cortex and greater histological damage in the interstitial arteries of male MatSep rats compared with control male rats. Plasma testosterone was greater and estradiol was lower in male MatSep rats compared with control rats with ANG II infusion. ANG II infusion failed to increase blood pressure in orchidectomized male MatSep and control rats. Female MatSep and control rats had similar Ccr, histological renal analysis, and sex hormones at baseline and after ANG II infusion. These data indicate that during ANG II-induced hypertension, MatSep sensitizes the renal phenotype in male but not female rats. PMID:23174859

  12. Kangaroo rat bone compared to white rat bone after short-term disuse and exercise

    USGS Publications Warehouse

    Muths, E.; Reichman, O. J.

    1996-01-01

    Kangaroo rats (Dipodomys ordii) were used to study the effects of confinement on mechanical properties of bone with a long range objective of proposing an alternative to the white rat model for the study of disuse osteoporosis. Kangaroo rats exhibit bipedal locomotion, which subjects their limbs to substantial accelerative forces in addition to the normal stress of weight bearing. We subjected groups of kangaroo rats and white rats (Rattus norvegicus) to one of two confinement treatments or to an exercise regime; animals were exercised at a rate calculated to replicate their (respective) daily exercise patterns. White laboratory rats were used as the comparison because they are currently the accepted model used in the study of disuse osteoporosis. After 6 weeks of treatment, rats were killed and the long bones of their hind limbs were tested mechanically and examined for histomorphometric changes. We found that kangaroo rats held in confinement had less ash content in their hind limbs than exercised kangaroo rats. In general, treated kangaroo rats showed morphometric and mechanical bone deterioration compared to controls and exercised kangaroo rats appeared to have slightly “stronger” bones than confined animals. White rats exhibited no significant differences between treatments. These preliminary results suggest that kangaroo rats may be an effective model in the study of disuse osteoporosis.

  13. Advances on genetic rat models of epilepsy

    PubMed Central

    Serikawa, Tadao; Mashimo, Tomoji; Kuramoto, Takashi; Voigt, Birger; Ohno, Yukihiro; Sasa, Masashi

    2014-01-01

    Considering the suitability of laboratory rats in epilepsy research, we and other groups have been developing genetic models of epilepsy in this species. After epileptic rats or seizure-susceptible rats were sporadically found in outbred stocks, the epileptic traits were usually genetically-fixed by selective breeding. So far, the absence seizure models GAERS and WAG/Rij, audiogenic seizure models GEPR-3 and GEPR-9, generalized tonic-clonic seizure models IER, NER and WER, and Canavan-disease related epileptic models TRM and SER have been established. Dissection of the genetic bases including causative genes in these epileptic rat models would be a significant step toward understanding epileptogenesis. N-ethyl-N-nitrosourea (ENU) mutagenesis provides a systematic approach which allowed us to develop two novel epileptic rat models: heat-induced seizure susceptible (Hiss) rats with an Scn1a missense mutation and autosomal dominant lateral temporal epilepsy (ADLTE) model rats with an Lgi1 missense mutation. In addition, we have established episodic ataxia type 1 (EA1) model rats with a Kcna1 missense mutation derived from the ENU-induced rat mutant stock, and identified a Cacna1a missense mutation in a N-Methyl-N-nitrosourea (MNU)-induced mutant rat strain GRY, resulting in the discovery of episodic ataxia type 2 (EA2) model rats. Thus, epileptic rat models have been established on the two paths: ‘phenotype to gene’ and ‘gene to phenotype’. In the near future, development of novel epileptic rat models will be extensively promoted by the use of sophisticated genome editing technologies. PMID:25312505

  14. Advances on genetic rat models of epilepsy.

    PubMed

    Serikawa, Tadao; Mashimo, Tomoji; Kuramoro, Takashi; Voigt, Birger; Ohno, Yukihiro; Sasa, Masashi

    2015-01-01

    Considering the suitability of laboratory rats in epilepsy research, we and other groups have been developing genetic models of epilepsy in this species. After epileptic rats or seizure-susceptible rats were sporadically found in outbred stocks, the epileptic traits were usually genetically-fixed by selective breeding. So far, the absence seizure models GAERS and WAG/Rij, audiogenic seizure models GEPR-3 and GEPR-9, generalized tonic-clonic seizure models IER, NER and WER, and Canavan-disease related epileptic models TRM and SER have been established. Dissection of the genetic bases including causative genes in these epileptic rat models would be a significant step toward understanding epileptogenesis. N-ethyl-N-nitrosourea (ENU) mutagenesis provides a systematic approach which allowed us to develop two novel epileptic rat models: heat-induced seizure susceptible (Hiss) rats with an Scn1a missense mutation and autosomal dominant lateral temporal epilepsy (ADLTE) model rats with an Lgi1 missense mutation. In addition, we have established episodic ataxia type 1 (EA1) model rats with a Kcna1 missense mutation derived from the ENU-induced rat mutant stock, and identified a Cacna1a missense mutation in a N-Methyl-N-nitrosourea (MNU)-induced mutant rat strain GRY, resulting in the discovery of episodic ataxia type 2 (EA2) model rats. Thus, epileptic rat models have been established on the two paths: 'phenotype to gene' and 'gene to phenotype'. In the near future, development of novel epileptic rat models will be extensively promoted by the use of sophisticated genome editing technologies. PMID:25312505

  15. Histomorphometric analysis of rat skeleton following spaceflight

    NASA Technical Reports Server (NTRS)

    Wronski, T. J.; Morey-Holton, E. R.; Doty, S. B.; Maese, A. C.; Walsh, C. C.

    1987-01-01

    Male Sprague-Dawley rats were placed in orbit for 7 days aboard the space shuttle. Bone histomorphometry was performed in the long bones and lumbar vertebrae of flight rats and compared with data derived from ground-based control rats. Trabecular bone mass was not altered during the 1st wk of weightlessness. Strong trends were observed in flight rats for decreased periosteal bone formation in the tibial diaphysis, reduced osteoblast size in the proximal tibia, and decreased osteoblast surface and number in the lumbar vertebra. For the most part, histological indexes of bone resorption were normal in flight rats. The results indicate that 7 days of weightlessness are not of sufficient duration to induce histologically detectable loss of trabecular bone in rats. However, cortical and trabecular bone formation appear to be diminished during the 1st wk of spaceflight.

  16. False context fear memory in rats.

    PubMed

    Bae, Sarah E; Holmes, Nathan M; Westbrook, R Frederick

    2015-10-01

    Four experiments used rats to study false context fear memories. In Experiment 1, rats were pre-exposed to a distinctive chamber (context A) or to a control environment (context C), shocked after a delay in a second chamber (context B) and tested either in B or A. Rats pre-exposed to A froze just as much as control rats in B but more than control rats in A. In Experiment 2, rats were pre-exposed to A or C, subjected to an immediate shock in B and tested in B or A. Rats pre-exposed to A froze when tested in A but did not freeze when tested in B and control rats did not freeze in either A or B. The false fear memory to the pre-exposed A was contingent on its similarity with the shocked B. In Experiment 3, rats pre-exposed to A and subjected to immediate shock in B froze when tested in A but did not freeze when tested in C and rats pre-exposed to C did not freeze when tested either in A or C. In Experiment 4, rats pre-exposed to A and subjected to immediate shock in B froze more when tested in A than rats whose pre-exposure to A began with an immediate shock. The results were discussed in terms of a dual systems explanation of context fear conditioning: a hippocampal-dependent process that forms a unitary representation of context and an amygdala-based process which associates this representation with shock. PMID:26373831

  17. Renal kallikrein in chronic hypoxic rats.

    PubMed

    Chen, C F; Chen, L W; Chien, C T; Wu, M S; Tsai, T J

    1996-09-01

    1. We have studied the role of kallikrein (KK) in the maintenance of renal function in chronic hypoxic rats (high altitude; HA), compared with control rats kept at sea level (SL). Hypoxia was induced by placing female Wistar rats (198-290 g) in an altitude chamber (5500 m) 15 h/day for 4 weeks. Experiments were also conducted to study the interaction of KK with renal nerve activity and endothelin (ET), two parameters previously shown to be altered in this model. 2. It was found that renal cortex tissue KK activity (TKA) was not significantly different in 10 SL and 10 HA rats. However, the urinary KK activity (UKA) was reduced nearly to half (from 35.2 +/- 4.6 to 18.5 +/- 1.7 pkat/min) in HA rats after 4 weeks of chronic hypoxia. 3. Acute renal denervated diuresis was accompanied by a significant increase in UKA (from 9 +/- 2 to 14 +/- 2 pkat/min in HA and denervated HA rats, respectively; P < 0.05) in HA rats. Intrarenal arterial pretreatment of aprotinin reduced the denervated diuresis. 4. Endothelin (600 ng/kg per h) reduced urine flow, sodium and potassium excretion in the ipsilateral kidney in another 10 SL and 10 HA rats. The extent of the drop of these parameters was significantly less in HA rats. Urinary KK activity was correlated significantly with the measured renal functional parameters (r ranging from 0.472 to 0.612) in SL rats, but was insignificant in HA rats (r ranging from 0.032 to 0.192). 5. We have demonstrated that chronic exposure to hypoxia decreases urinary KK excretion and that KK is involved in acute renal denervated diuresis generated in these animals. The present study suggests that KK plays a partial role in the maintenance of renal function in chronic hypoxic rats. PMID:8911720

  18. Protective Vaccination against Papillomavirus-Induced Skin Tumors under Immunocompetent and Immunosuppressive Conditions: A Preclinical Study Using a Natural Outbred Animal Model

    PubMed Central

    Vinzón, Sabrina E.; Braspenning-Wesch, Ilona; Müller, Martin; Geissler, Edward K.; Nindl, Ingo; Gröne, Hermann-Josef

    2014-01-01

    Certain cutaneous human papillomaviruses (HPVs), which are ubiquitous and acquired early during childhood, can cause a variety of skin tumors and are likely involved in the development of non-melanoma skin cancer, especially in immunosuppressed patients. Hence, the burden of these clinical manifestations demands for a prophylactic approach. To evaluate whether protective efficacy of a vaccine is potentially translatable to patients, we used the rodent Mastomys coucha that is naturally infected with Mastomys natalensis papillomavirus (MnPV). This skin type papillomavirus induces not only benign skin tumours, such as papillomas and keratoacanthomas, but also squamous cell carcinomas, thereby allowing a straightforward read-out for successful vaccination in a small immunocompetent laboratory animal. Here, we examined the efficacy of a virus-like particle (VLP)-based vaccine on either previously or newly established infections. VLPs raise a strong and long-lasting neutralizing antibody response that confers protection even under systemic long-term cyclosporine A treatment. Remarkably, the vaccine completely prevents the appearance of benign as well as malignant skin tumors. Protection involves the maintenance of a low viral load in the skin by an antibody-dependent prevention of virus spread. Our results provide first evidence that VLPs elicit an effective immune response in the skin under immunocompetent and immunosuppressed conditions in an outbred animal model, irrespective of the infection status at the time of vaccination. These findings provide the basis for the clinical development of potent vaccination strategies against cutaneous HPV infections and HPV-induced tumors, especially in patients awaiting organ transplantation. PMID:24586150

  19. Isolation of rat adrenocortical mitochondria

    SciTech Connect

    Solinas, Paola; Fujioka, Hisashi; Tandler, Bernard; Hoppel, Charles L.

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer A method for isolation of adrenocortical mitochondria from the adrenal gland of rats is described. Black-Right-Pointing-Pointer The purified isolated mitochondria show excellent morphological integrity. Black-Right-Pointing-Pointer The properties of oxidative phosphorylation are excellent. Black-Right-Pointing-Pointer The method increases the opportunity of direct analysis of adrenal mitochondria from small animals. -- Abstract: This report describes a relatively simple and reliable method for isolating adrenocortical mitochondria from rats in good, reasonably pure yield. These organelles, which heretofore have been unobtainable in isolated form from small laboratory animals, are now readily accessible. A high degree of mitochondrial purity is shown by the electron micrographs, as well as the structural integrity of each mitochondrion. That these organelles have retained their functional integrity is shown by their high respiratory control ratios. In general, the biochemical performance of these adrenal cortical mitochondria closely mirrors that of typical hepatic or cardiac mitochondria.

  20. Modeling nicotine addiction in rats.

    PubMed

    Caille, Stephanie; Clemens, Kelly; Stinus, Luis; Cador, Martine

    2012-01-01

    Among the human population, 15% of drug users develop a pathological drug addiction. This figure increases substantially with nicotine, whereby more than 30% of those who try smoking develop a nicotine addiction. Drug addiction is characterized by compulsive drug-seeking and drug-taking behaviors (craving), and loss of control over intake despite impairment in health, social, and occupational functions. This behavior can be accurately modeled in the rat using an intravenous self-administration (IVSA) paradigm. Initial attempts at establishing nicotine self-administration had been problematic, yet in recent times increasingly reliable models of nicotine self-administration have been developed. The present article reviews different characteristics of the nicotine IVSA model that has been developed to examine nicotine reinforcing and motivational properties in rats. PMID:22231818

  1. Lead induced testicular hypersensitivity in stressed rats.

    PubMed

    Saxena, D K; Lal, B; Srivastava, R S; Chandra, S V

    1990-01-01

    Rats were immobilized for 2 h and treated i.p. with lead Pb2+ (8 mg/kg/day) for 45 d to investigate the testicular effects of lead on rats kept under immobilization stress. Marked alteration in SDH. G6PDH activity, cholesterol and ascorbic acid contents and reduced sperm counts associated with marked pathological changes in the testis of rats were observed after combined treatment with lead and immobilization stress in comparison to either alone. An increase in the disturbances of testicular androgen synthesis seems to be responsible for enhanced testicular injury in lead induced stressed rats. PMID:2401350

  2. Hyperammonemia in anorectic tumor-bearing rats

    SciTech Connect

    Chance, W.T.; Cao, L.; Nelson, J.L.; Foley-Nelson, T.; Fischer, J.E.

    1988-01-01

    Plasma ammonia concentrations were significantly elevated by 150% in anorectic rats bearing methylcholanthrene sarcomas. Assessment of ammonia levels in blood draining these sarcomas indicated nearly a 20-fold increase as compared with venous blood in control rats, suggesting the tumor mass as the source of this increase in ammonia. Infusing increasing concentrations of ammonium salts produced anorexia and alterations in brain amino acids in normal rats that were similar to those observed in anorectic tumor-bearing rats. Therefore, these results suggest that ammonia released by tumor tissue may be an important factor in the etiology of cancer anorexia.

  3. Toxicity and repellency to rats of actidione

    USGS Publications Warehouse

    Traub, R.; DeWitt, J.B.; Welch, J.F.; Newman, D.

    1950-01-01

    The antibiotic actidione was found to be highly repellent to laboratory rats and to significantly reduce gnawing attacks upon treated paperboards. Rats refused to accept food or water containing this material even under conditions of acute starvation and died of starvation and thirst,rather than accept water containing l.0 mg. of actidione per liter. The compound is highly toxic to .rats with the minimum .lethal dose by oral administration being approximately l.0 mg./Kg body weight. Paperboard treated with the compound resisted gnawing attacks by specially trained and motivated rats for periods of two hundred hours, although similar .untreated boards were pierced within thirty-to sixty minutes.

  4. Automatic Training of Rat Cyborgs for Navigation

    PubMed Central

    Yu, Yipeng; Wu, Zhaohui; Xu, Kedi; Gong, Yongyue; Zheng, Nenggan; Zheng, Xiaoxiang; Pan, Gang

    2016-01-01

    A rat cyborg system refers to a biological rat implanted with microelectrodes in its brain, via which the outer electrical stimuli can be delivered into the brain in vivo to control its behaviors. Rat cyborgs have various applications in emergency, such as search and rescue in disasters. Prior to a rat cyborg becoming controllable, a lot of effort is required to train it to adapt to the electrical stimuli. In this paper, we build a vision-based automatic training system for rat cyborgs to replace the time-consuming manual training procedure. A hierarchical framework is proposed to facilitate the colearning between rats and machines. In the framework, the behavioral states of a rat cyborg are visually sensed by a camera, a parameterized state machine is employed to model the training action transitions triggered by rat's behavioral states, and an adaptive adjustment policy is developed to adaptively adjust the stimulation intensity. The experimental results of three rat cyborgs prove the effectiveness of our system. To the best of our knowledge, this study is the first to tackle automatic training of animal cyborgs. PMID:27436999

  5. Methanethiol metabolism in the rat

    SciTech Connect

    Derr, R.F.; Draves, K.

    1983-03-01

    Methanethiol is associated with hepatic failure in humans and the synergistic action of methanethiol, ammonia and octanoate is sufficient to account for the coma of experimental hepatic necrosis. The sulfur atom of methanethiol is eliminated from the body as urinary sulfate at a rate which is approximated by a hyperbola such that 94% is excreted within 21 h after administration. Rats in octanoate or hepatic coma excreted only little sulfate in their urine.

  6. Pathophysiology of the Belgrade rat

    PubMed Central

    Veuthey, Tania; Wessling-Resnick, Marianne

    2014-01-01

    The Belgrade rat is an animal model of divalent metal transporter 1 (DMT1) deficiency. This strain originates from an X-irradiation experiment first reported in 1966. Since then, the Belgrade rat’s pathophysiology has helped to reveal the importance of iron balance and the role of DMT1. This review discusses our current understanding of iron transport homeostasis and summarizes molecular details of DMT1 function. We describe how studies of the Belgrade rat have revealed key roles for DMT1 in iron distribution to red blood cells as well as duodenal iron absorption. The Belgrade rat’s pathology has extended our knowledge of hepatic iron handling, pulmonary and olfactory iron transport as well as brain iron uptake and renal iron handling. For example, relationships between iron and manganese metabolism have been discerned since both are essential metals transported by DMT1. Pathophysiologic features of the Belgrade rat provide us with a unique and interesting animal model to understand iron homeostasis. PMID:24795636

  7. Analysis of rat cytosolic 9-cis-retinol dehydrogenase activity and enzymatic characterization of rat ADHII.

    PubMed

    Popescu, G; Napoli, J L

    2000-01-01

    We report the characterization of two enzymes that catalyze NAD(+)-dependent 9-cis-retinol dehydrogenase activity in rat liver cystol. Alcohol dehydrogenase class I (ADHI) contributes > 80% of the NA D+-dependent 9-cis-retinol dehydrogenase activity recovered, whereas alcohol dehydrogenase class II (ADHII), not identified previously at the protein level, nor characterized enzymatically in rat, accounts for approximately 2% of the activity. Rat ADHII exhibits properties different from those described for human ADHII. Moreover, rat ADHII-catalyzed rates of ethanol dehydrogenation are markedly lower than octanol or retinoid dehydrogenation rates. Neither ethanol nor 4-methylpyrazole inhibits the 9-cis-retinol dehydrogenase activity of rat ADHII. We propose that ADHII represents the previously observed additional retinoid oxidation activity of rat liver cytosol which occurred in the presence of either ethanol or 4-methylpyrazole. We also show that human and rat ADHII differ considerably in enzymatic properties. PMID:10606766

  8. Synthesis of HDL apolipoproteins by rat hepatocytes

    SciTech Connect

    Hussain, M.M.; Kelley, M.; Zannis, V.I.

    1986-05-01

    The authors have used 2D-PAGE to study the synthesis, intracellular modification, and secretion of rat HDL apolipoproteins by primary cultures of rat hepatocytes. ApoA-IV, apoA-II and apoE synthesized after a 10 min pulse with /sup 35/S-methionine coincided on 2D-gels with their corresponding plasma forms and they were not modified further intracellularly or following secretion. A fraction (< 10%) of apoE was modified intracellularly to minor isoprotein forms that were insensitive to neuraminidase treatment. These later forms also constituted a minor component of the secreted and plasma rat apoE. The intracellular and newly secreted apoA-I differed from its plasma counterpart by -1 charge as described previously. The intracellular forms of rat apoA-I, apoA-IV and unmodified apoE differed from the products of cell free translation of rat liver mRNA by +1 charge. Their findings (a) establish the charge relationship between nascent and plasma rat apolipoproteins, (b) indicate that rat apoA-I, apoA-II and apoA-IV are not modified intracellularly, (c) suggest that there is a difference in the post-translational modification patterns between the rat and human hepatic apoE.

  9. Stimulus Over-Selectivity in Rats

    ERIC Educational Resources Information Center

    Gibson, Evelyn; Reed, Phil

    2005-01-01

    The present study explored whether a similar phenomenon to stimulus over-selectivity occurred in rats, in the hope of establishing a non-human model for the autism. Rats were serially presented with two-15 seconds, two-element compound stimuli prior to the delivery of food, in an appetitive classical conditioning procedure. Each compound stimulus…

  10. Distal axonopathy in streptozotocin diabetes in rats.

    PubMed

    Chokroverty, S; Seiden, D; Navidad, P; Cody, R

    1988-05-15

    We noted the earliest morphological changes in the motor endplates 8 weeks after the induction of streptozotocin diabetes in rats. Morphometric measurements showed reduced axonal areas of the lateral plantar and the sciatic nerves in the diabetic rats 28 but not 2 and 8 weeks after the experiment. These findings suggested distal axonopathy. PMID:3371449

  11. ALLYLISOPROPYLACETAMIDE INDUCES RAT HEPATIC ORNITHINE DECARBOXYLASE

    EPA Science Inventory

    In rat liver, allylisopropylacetamide (AIA) treatment strongly induced (25-fold) the activity of rat hepatic ornithine decarboxylase (ODC). y either the oral or the subcutaneous routes, AIA produced a long-lasting induction (30 to 4O hours) of hepatic ODC activity. hree analogs o...

  12. Spatial Memory in Rats after 25 Hours

    ERIC Educational Resources Information Center

    Crystal, Jonathon D.; Babb, Stephanie J.

    2008-01-01

    We investigated the time course of spatial-memory decay in rats using an eight-arm radial maze. It is well established that performance remains high with retention intervals as long as 4 h, but declines to chance with a 24-h retention interval (Beatty, W. W., & Shavalia, D. A. (1980b). Spatial memory in rats: time course of working memory and…

  13. THERMAL BIOLOGY OF THE LABORATORY RAT

    EPA Science Inventory

    In view of the array of thermal interactions commonly reported in physiological, pharmacological and behavioral studies of the rat, it would be timely to thoroughly review and develop a data base of the basic thermoregulatory parameters of the laboratory rat. his review contains ...

  14. Same-Different Categorization in Rats

    ERIC Educational Resources Information Center

    Wasserman, Edward A.; Castro, Leyre; Freeman, John H.

    2012-01-01

    Same-different categorization is a fundamental feat of human cognition. Although birds and nonhuman primates readily learn same-different discriminations and successfully transfer them to novel stimuli, no such demonstration exists for rats. Using a spatial discrimination learning task, we show that rats can both learn to discriminate arrays of…

  15. GLUTAMINE CYCLING IN ISOLATED WORKING RAT HEART

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To what extent does glutamine turnover keep pace with oxidative metabolism in the rat heart? To address this question, the following substrates were presented to the isolated, working rat heart: (1) glucose (5 mM), insulin (40 mU/ml) and [2-13C]acetate (5mM) (high workload, n= 5); (2) pyruvate (2....

  16. EYEBLINK CONDITIONING IN THE DEVELOPING RAT

    EPA Science Inventory

    Long-Evans rat pups, 17-18 or 24 days of age, wore trained with an eyeblink conditioning (EBC) procedure that has recently been used with adult rats (Skelton, 1988, Beh, Neurosci., 102, 586-590). ups received 3 sessions of delay conditioning in a single day, at about 4 hour inter...

  17. PBPK MODELING OF DELTAMETHRIN IN RATS

    EPA Science Inventory

    The pyrethroid pesticide deltamethrin is cleared nearly twice as rapidly in human liver microsomes compared to rat liver microsomes. A species difference such as this could influence the toxic potency of deltamethrin between rats and humans. PBPK modeling is a tool that can be ut...

  18. Cryopreservation and orthotopic transplantation of rat ovaries.

    PubMed

    Dorsch, Martina; Wedekind, Dirk

    2010-01-01

    The number of rat strains increased considerably in the last decade and will increase continuously during the next years. This requires enough space for maintaining vital strains and techniques for cryobanking, which can be applied not only in specialised rat resource centres but also in regular animal houses. Here we describe an easy and fast method for the cryopreservation and transplantation of frozen-thawed ovaries of the rat. With dimethyl sulfoxide as cryoprotectant rat ovaries can be stored at -196 degrees C for unlimited time. For revitalisation thawed ovaries have to be orthotopically transplanted into appropriate ovarectomised recipients. Reestablishment of the reproductive cycle in the recipients can be confirmed by vaginal cytology shortly after transplantation. The recipients are able to produce 2-3 litters after mating with males of an appropriate strain. Cyropreservation of ovaries thus can be considered a reliable method to preserve scientifically and economically important stocks and strains of rats that are currently not required. PMID:20013242

  19. Glycine metabolism in rat kidney cortex slices.

    PubMed

    Rowsell, E V; Al-Naama, M M; Rowsell, K V

    1982-04-15

    When rat kidney cortex slices were incubated with glycine or [1-14C]glycine, after correcting for metabolite changes with control slices, product formation and glycine utilization fitted the requirements of the equation: 2 Glycine leads to ammonia + CO2 + serine. Evidence is presented that degradation via glyoxylate, by oxidation or transamination, is unlikely to have any significant role in kidney glycine catabolism. It is concluded that glycine metabolism in rat kidney is largely via glycine cleavage closely coupled with serine formation. 1-C decarboxylation and urea formation with glycine in rat hepatocyte suspensions were somewhat greater than decarboxylation or ammonia formation in kidney slices, showing that in the rat, potentially, the liver is quantitatively the more important organ in glycine catabolism. There was no evidence of ammonia formation from glycine with rat brain cortex, heart, spleen or diaphragm and 1-C decarboxylation was very weak. PMID:6810880

  20. Mitochondrial DNA phylogeography of the Norway rat.

    PubMed

    Song, Ying; Lan, Zhenjiang; Kohn, Michael H

    2014-01-01

    Central Eastern Asia, foremost the area bordering northern China and Mongolia, has been thought to be the geographic region where Norway rats (Rattus norvegicus) have originated. However recent fossil analyses pointed to their origin in southern China. Moreover, whereas analyses of fossils dated the species' origin as ∼ 1.2-1.6 million years ago (Mya), molecular analyses yielded ∼ 0.5-2.9 Mya. Here, to study the geographic origin of the Norway rat and its spread across the globe we analyzed new and all published mitochondrial DNA cytochrome-b (cyt-b; N = 156) and D-loop (N = 212) sequences representing wild rats from four continents and select inbred strains. Our results are consistent with an origin of the Norway rat in southern China ∼ 1.3 Mya, subsequent prehistoric differentiation and spread in China and Asia from an initially weakly structured ancestral population, followed by further spread and differentiation across the globe during historic times. The recent spreading occurred mostly from derived European populations rather than from archaic Asian populations. We trace laboratory strains to wild lineages from Europe and North America and these represent a subset of the diversity of the rat; leaving Asian lineages largely untapped as a resource for biomedical models. By studying rats from Europe we made the observation that mtDNA diversity cannot be interpreted without consideration of pest control and, possibly, the evolution of rodenticide resistance. However, demographic models explored by forward-time simulations cannot fully explain the low mtDNA diversity of European rats and lack of haplotype sharing with their source from Asia. Comprehensive nuclear marker analyses of a larger sample of Norway rats representing the world are needed to better resolve the evolutionary history of wild rats and of laboratory rats, as well as to better understand the evolution of anticoagulant resistance. PMID:24586325

  1. Is fructose sweeter than glucose for rats?

    PubMed

    Ramirez, I

    1996-11-01

    Because it is generally thought that the intensity of the taste of fructose is greater than that of glucose for rats, it seemed surprising when sham-fed rats drank substantially less of a mixture of 6% fructose plus saccharin than of a mixture of 6% glucose plus saccharin. At least 3 different factors contribute to this effect. First, the taste of fructose is less attractive to rats than is the taste of glucose; sham-fed rats strongly preferred glucose over fructose (no saccharin was used in this experiment). The second factor is experience. Rats having substantial previous experience with glucose, but not with fructose, consistently preferred glucose over fructose. Conversely, rats having substantial previous experience with fructose, but not with glucose, initially showed no consistent preference but subsequently tended to prefer glucose. The third factor is an interaction between saccharin and the type of sugar. Rats given only one solution at a time drink approximately as much fructose as glucose when the solutions contain no saccharin. The addition of 0.25% saccharin to 6% glucose stimulated intake, whereas the addition of the same amount of saccharin to 6% fructose did not stimulate intake. As a result, rats ingested substantially more of a mixture of 0.25% saccharin plus 6% glucose than they did of a comparable mixture of saccharin and fructose, even though rats ingest similar amounts of fructose and glucose without saccharin in single-bottle tests. Because the differential effect of saccharin on intake appeared within 2 h in naive rats, and did not greatly change over a 3-day period, it is probably not attributable to conditioning. These results suggest that these sugars have qualitatively different tastes. PMID:8916185

  2. Mitochondrial DNA Phylogeography of the Norway Rat

    PubMed Central

    Song, Ying; Lan, Zhenjiang; Kohn, Michael H.

    2014-01-01

    Central Eastern Asia, foremost the area bordering northern China and Mongolia, has been thought to be the geographic region where Norway rats (Rattus norvegicus) have originated. However recent fossil analyses pointed to their origin in southern China. Moreover, whereas analyses of fossils dated the species' origin as ∼1.2–1.6 million years ago (Mya), molecular analyses yielded ∼0.5–2.9 Mya. Here, to study the geographic origin of the Norway rat and its spread across the globe we analyzed new and all published mitochondrial DNA cytochrome-b (cyt-b; N = 156) and D-loop (N = 212) sequences representing wild rats from four continents and select inbred strains. Our results are consistent with an origin of the Norway rat in southern China ∼1.3 Mya, subsequent prehistoric differentiation and spread in China and Asia from an initially weakly structured ancestral population, followed by further spread and differentiation across the globe during historic times. The recent spreading occurred mostly from derived European populations rather than from archaic Asian populations. We trace laboratory strains to wild lineages from Europe and North America and these represent a subset of the diversity of the rat; leaving Asian lineages largely untapped as a resource for biomedical models. By studying rats from Europe we made the observation that mtDNA diversity cannot be interpreted without consideration of pest control and, possibly, the evolution of rodenticide resistance. However, demographic models explored by forward-time simulations cannot fully explain the low mtDNA diversity of European rats and lack of haplotype sharing with their source from Asia. Comprehensive nuclear marker analyses of a larger sample of Norway rats representing the world are needed to better resolve the evolutionary history of wild rats and of laboratory rats, as well as to better understand the evolution of anticoagulant resistance. PMID:24586325

  3. Social exclusion intensifies anxiety-like behavior in adolescent rats.

    PubMed

    Lee, Hyunchan; Noh, Jihyun

    2015-05-01

    Social connection reduces the physiological reactivity to stressors, while social exclusion causes emotional distress. Stressful experiences in rats result in the facilitation of aversive memory and induction of anxiety. To determine the effect of social interaction, such as social connection, social exclusion and equality or inequality, on emotional change in adolescent distressed rats, the emotional alteration induced by restraint stress in individual rats following exposure to various social interaction circumstances was examined. Rats were assigned to one of the following groups: all freely moving rats, all rats restrained, rats restrained in the presence of freely moving rats and freely moving rats with a restrained rat. No significant difference in fear-memory and sucrose consumption between all groups was found. Change in body weight significantly increased in freely moving rats with a restrained rat, suggesting that those rats seems to share the stressful experience of the restrained rat. Interestingly, examination of the anxiety-like behavior revealed only rats restrained in the presence of freely moving rats to have a significant increase, suggesting that emotional distress intensifies in positions of social exclusion. These results demonstrate that unequally excluded social interaction circumstances could cause the amplification of distressed status and anxiety-related emotional alteration. PMID:25680679

  4. Identity Matching-to-Sample with Olfactory Stimuli in Rats

    ERIC Educational Resources Information Center

    Pena, Tracy; Pitts, Raymond C.; Galizio, Mark

    2006-01-01

    Identity matching-to-sample has been difficult to demonstrate in rats, but most studies have used visual stimuli. There is evidence that rats can acquire complex forms of olfactory stimulus control, and the present study explored the possibility that identity matching might be facilitated in rats if olfactory stimuli were used. Four rats were…

  5. Glucagon Metabolism in the Rat

    PubMed Central

    Emmanouel, D. S.; Jaspan, J. B.; Rubenstein, A. H.; Huen, A. H-J.; Fink, E.; Katz, A. I.

    1978-01-01

    The renal handling of the biologically active glucagon component (the 3,500-mol wt fraction of immunoreactive glucagon [IRG]) and the contribution of the kidney to its overall peripheral metabolism were studied in normal and uremic rats. The metabolic clearance rate of glucagon was 31.8 ± 1.2 ml/min per kg in normal animals and was diminished by approximately one-third in each of three groups of rats with compromized renal function: 22.3±1.6 ml/min per kg in partially (70%) nephrectomized; 22.9±3.3 ml/min per kg in bilaterally ureteral ligated; and 23.2±1.2 ml/min per kg in bilaterally nephrectomized animals. In normal rats the kidney contributed 30% to the overall metabolic clearance of the hormone and the renal extraction of endogenous and exogenous glucagon was similar, averaging 22.9±1.6% and was independent of plasma IRG levels over a wide range of arterial concentrations. The remnant kidney of partially (70%) nephrectomized animals continued to extract substantial amounts (16.6±4.2%) of the hormone, but accounted for only 8% of the total peripheral catabolism of IRG. In the two groups of animals with filtering kidneys, renal glucagon uptake was linearly related to its filtered load and could be accounted for by glomerular filtration and tubular reabsorption. However, the kidneys of animals with both ureters ligated (renal extraction of inulin = 3.2±1.8%) and hence virtual absence of glomerular filtration, continued to extract 11.5±1.9% of the renal arterial glucagon, contributing by 9% to its overall metabolic clearance, indicating that IRG uptake occurs also from the post glomerular capillaries. PMID:659638

  6. Retained folates in the rat.

    PubMed Central

    Barford, P A; Staff, R J; Blair, J A

    1977-01-01

    The retention of radioactivity after doses of 14C- and 3H-labelled folic acid is described. Radioactivity was retained in liver, kidney and gut of rats for some time after administration of the dose. The retained radioactivity could not be displaced by large doses of unlabelled folic acid or unlabelled 5-methyltetrahydrofolate. 14C- and 3H-labbelled folates showed similar chromatographic behaviour onion-exchange chromatography to 5-methyltetrahydrofolate, and on ion-exchange and gel-permeation chromatography to synthetic pteroylhepta-gamma-glutamate. PMID:883955

  7. Anxiolytic Treatment Impairs Helping Behavior in Rats.

    PubMed

    Ben-Ami Bartal, Inbal; Shan, Haozhe; Molasky, Nora M R; Murray, Teresa M; Williams, Jasper Z; Decety, Jean; Mason, Peggy

    2016-01-01

    Despite decades of research with humans, the biological mechanisms that motivate an individual to help others remain poorly understood. In order to investigate the roots of pro-sociality in mammals, we established the helping behavior test, a paradigm in which rats are faced with a conspecific trapped in a restrainer that can only be opened from the outside. Over the course of repeated test sessions, rats exposed to a trapped cagemate learn to open the door to the restrainer, thereby helping the trapped rat to escape (Ben-Ami Bartal et al., 2011). The discovery of this natural behavior provides a unique opportunity to probe the motivation of rodent helping behavior, leading to a deeper understanding of biological influences on human pro-sociality. To determine if an affective response motivates door-opening, rats receiving midazolam, a benzodiazepine anxiolytic, were tested in the helping behavior test. Midazolam-treated rats showed less helping behavior than saline-treated rats or rats receiving no injection. Yet, midazolam-treated rats opened a restrainer containing chocolate, highlighting the socially specific effects of the anxiolytic. To determine if midazolam interferes with helping through a sympatholytic effect, the peripherally restricted beta-adrenergic receptor antagonist nadolol was administered; nadolol did not interfere with helping. The corticosterone response of rats exposed to a trapped cagemate was measured and compared to the rats' subsequent helping behavior. Rats with the greatest corticosterone responses showed the least helping behavior and those with the smallest responses showed the most consistent helping at the shortest latency. These results are discussed in terms of their implications for the interaction between stress and pro-social behavior. Finally, we observed that door-opening appeared to be reinforcing. A novel analytical tool was designed to interrogate the pattern of door-opening for signs that a rat's behavior on one session

  8. Electroencephalographic changes in albino rats subjected to stress

    NASA Technical Reports Server (NTRS)

    Mercier, J.; Assouline, G.; Fondarai, J.

    1980-01-01

    Twenty one albino Wistar rats were subjected to stress for 7 hours. There was a significant difference in the slopes of regression lines for 7 nonulcerous rats and those for 14 ulcerous rats. Nonulcerous rats subjected to stress showed greater EEG curve synchronization than did ulcerous rats. If curve synchronization can be equated to a relaxed state, it may therefore be possible to explain the protective action of hypnotics, tranquilizers and analgesics on ulcers.

  9. The long pursued Holy Grail of the true "alcoholic" rat.

    PubMed

    Gessa, Gian Luigi

    2016-08-15

    An anthology of microdialysis and electrophysiological studies on ethanol effect on mesolimbic dopaminergic neurons is presented. The usefulness of rats with innate preference for ethanol, such as the Sardinian alcohol-preferring (sP), in studying ethanol rewarding and reinforcing effects is signaled. The generation of the long sought "alcoholics rat" from sP rats is announced. Rats of the sP line avoid the shortcomings of using rats non selected for ethanol preference. PMID:26867703

  10. Analysis of vkorc1 polymorphisms in Norway rats using the roof rat as outgroup

    PubMed Central

    2010-01-01

    Background Certain mutations in the vitamin K epoxide reductase subcomponent 1 gene (vkorc1) mediate rodent resistance to warfarin and other anticoagulants. Testing for resistance often involves analysis of the vkorc1. However, a genetic test for the roof rat (Rattus rattus) has yet to be developed. Moreover, an available roof rat vkorc1 sequence would enable species identification based on vkorc1 sequence and the evaluation of natural selection on particular vkorc1 polymorphisms in the Norway rat (R. norvegicus). Results We report the coding sequence, introns and 5' and 3' termini for the vkorc1 gene of roof rats (R. r. alexandrinus and R. r. frugivorus) from Uganda, Africa. Newly designed PCR primers now enable genetic testing of the roof rat and Norway rat. Only synonymous and noncoding polymorphisms were found in roof rats from Uganda. Both nominal subspecies of roof rats were indistinguishable from each other but were distinct from R. losea and R. flavipectus; however, the roof rat also shares at least three coding sequence polymorphisms with R. losea and R. flavipectus. Many of recently published vkorc1 synonymous and non-synonymous single nucleotide polymorphisms (SNPs) in Norway rats are likely SNPs from roof rats and/or other Rattus species. Tests applied to presumably genuine Norway rat vkorc1 SNPs are consistent with a role for selection in two populations carrying the derived Phe63Cys and Tyr139Cys mutations. Conclusion Geographic mapping of vkorc1 SNPs in roof rats should be facilitated by our report. Our assay should be applicable to most species of Rattus, which are intermediate in genetic distance from roof and Norway rats. Vkorc1-mediated resistance due to non-synonymous coding SNPs is not segregating in roof rats from Uganda. By using the roof rat sequence as a reference vkorc1, SNPs now can be assigned to the correct rat species with more confidence. Sampling designs and genotyping strategies employed so far have helped detect candidate mutations

  11. Metabolism of ochratoxin A by rats.

    PubMed Central

    Støren, O; Holm, H; Størmer, F C

    1982-01-01

    Albino rats were given ochratoxin A (6.6 mg/kg body weight) intraperitoneally or per os. Independent of route administration, 6% of a given dose was excreted as the toxin, 1 to 1.5% as (4R)-4-hydroxyochratoxin A, and 25 to 27% as ochratoxin alpha in the urine. The metabolite (4S)-4-hydroxyochratoxin A, which is formed by rat liver microsomes in the presence of NADPH, was not detected. Only traces of ochratoxins A and alpha were found in feces. Identical experiments were carried out with brown rats, since the Km value for the formation of the 4S epimer was considerably lower when brown rat microsomes were used. About the same ratios of metabolites and metabolite recoveries as those found for albino rats were found for brown rats. Brown rats were also given the two hydroxylated metabolites and ochratoxin alpha (0.66 mg/kg body weight) intraperitoneally. The three compounds were excreted in the urine; within 48 h, 90% recovery of ochratoxin alpha and 54 and 35%, respectively, of the 4R and 4S isomers were observed. PMID:7149712

  12. Total parenteral nutrition in diabetic rats

    SciTech Connect

    Norcross, E.D.; Stein, T.P.

    1986-03-01

    Parenteral Nutrition with hypertonic glucose is frequently given to diabetic patients. Large amounts of insulin can be required. The purpose of this investigation was to develop a totally parenterally nourished diabetic rat model. 200 g Female Sprague Dawley rats were made diabetic by i.v. injection of streptozotocin (50 mg/kg). Rats were then allowed to recover for at least 1 week before undergoing surgical insertion of a central venous catheter for parenteral feeding. TPN was begun 3 days after surgery. Prior to this they were allowed unlimited access to food and water. Control (non-streptozotocin treated) rats were run at the same time. Protein turnover was investigated by using /sup 15/N glycine. Preliminary results: diabetic rats given mostly fat as a calorie source survived well in the absence of exogenous insulin whereas those that were given glucose only as their non-protein calorie source showed poor survival even with exogenous insulin. N balance and protein turnover in the lipid treated diabetic rats were comparable to the non-diabetic control rats.

  13. Radiation and G tolerance in rats

    SciTech Connect

    Mattsson, J.L.; Cordts, R.E.; Deyak, R.R. Jr.

    1981-07-01

    Male hooded rats were exposed to 2100 rad 60Co radiation and 18 h later were exposed to +Gz acceleration until heart rate was reduced to 50% of baseline rate. G tolerance was 9.2% less in irradiated rats than in controls. Although small, this difference was significant at p less than 0.05. A similar group of rats was anesthetized 18 h postirradiation and carotid mean arterial pressures were measured. Mean arterial pressure was 122.1 torr for controls and 114.5 for irradiated. This difference was not significant.

  14. Skeletal muscle metabolism in hypokinetic rats

    NASA Technical Reports Server (NTRS)

    Tischler, M. E.

    1984-01-01

    Muscle growth, protein metabolism, and amino acid metabolism were studied in various groups of rats. Certain groups were adrenaliectomized; some rats were suspended while others (the controls) were weight bearing. Results show that: (1) metabolic changes in the extensor digitorum longus muscle of suspended rats are due primarily to increased circulating glucocorticoids; (2) metabolic changes in the soleus muscle due to higher steroid levels are probably potentiated by greater numbers of steroid receptors; and (3) not all metabolic responses of the soleus muscle to unloading are due to the elevated levels of glucocorticoids or the increased sensitivity of this muscle to these hormones.

  15. Rats are the smart choice: Rationale for a renewed focus on rats in behavioral genetics

    PubMed Central

    Parker, Clarissa C.; Chen, Hao; Flagel, Shelly B.; Geurts, Aron M.; Richards, Jerry B.; Robinson, Terry E.; Solberg Woods, Leah C.; Palmer, Abraham A.

    2013-01-01

    Due in part to their rich behavioral repertoire rats have been widely used in behavioral studies of drug abuse-related traits for decades. However, the mouse became the model of choice for researchers exploring the genetic underpinnings of addiction after the first mouse study was published demonstrating the capability of engineering the mouse genome through embryonic stem cell technology. The sequencing of the mouse genome and more recent re-sequencing of numerous inbred mouse strains has further cemented the status of mice as the premier mammalian organism for genetic studies. As a result, many of the behavioral paradigms initially developed and optimized for rats have been adapted to mice. However, numerous complex and interesting drug abuse-related behaviors that can be studied in rats are very difficult or impossible to adapt for use in mice, impeding the genetic dissection of those traits. Now, technological advances have removed many of the historical limitations of genetic studies in rats. For instance, the rat genome has been sequenced and many inbred rat strains are now being re-sequenced and outbred rat stocks are being used to fine-map QTLs. In addition, it is now possible to create “knockout” rats using zinc finger nucleases (ZFN), transcription activator-like effector nucleases (TALENs) and related techniques. Thus, rats can now be used to perform quantitative genetic studies of sophisticated behaviors that have been difficult or impossible to study in mice. PMID:23791960

  16. Rat Bite Fever Resembling Rheumatoid Arthritis.

    PubMed

    Akter, Ripa; Boland, Paul; Daley, Peter; Rahman, Proton; Al Ghanim, Nayef

    2016-01-01

    Rat bite fever is rare in Western countries. It can be very difficult to diagnose as blood cultures are typically negative and a history of rodent exposure is often missed. Unless a high index of suspicion is maintained, the associated polyarthritis can be mistaken for rheumatoid arthritis. We report a case of culture-positive rat bite fever in a 46-year-old female presenting with fever and polyarthritis. The clinical presentation mimicked rheumatoid arthritis. Infection was complicated by discitis, a rare manifestation. We discuss the diagnosis and management of this rare zoonotic infection. We also review nine reported cases of rat bite fever, all of which had an initial presumptive diagnosis of a rheumatological disorder. Rat bite fever is a potentially curable infection but can have a lethal course if left untreated. PMID:27366177

  17. Rat Bite Fever Resembling Rheumatoid Arthritis

    PubMed Central

    Akter, Ripa; Boland, Paul; Daley, Peter; Rahman, Proton; Al Ghanim, Nayef

    2016-01-01

    Rat bite fever is rare in Western countries. It can be very difficult to diagnose as blood cultures are typically negative and a history of rodent exposure is often missed. Unless a high index of suspicion is maintained, the associated polyarthritis can be mistaken for rheumatoid arthritis. We report a case of culture-positive rat bite fever in a 46-year-old female presenting with fever and polyarthritis. The clinical presentation mimicked rheumatoid arthritis. Infection was complicated by discitis, a rare manifestation. We discuss the diagnosis and management of this rare zoonotic infection. We also review nine reported cases of rat bite fever, all of which had an initial presumptive diagnosis of a rheumatological disorder. Rat bite fever is a potentially curable infection but can have a lethal course if left untreated. PMID:27366177

  18. Rat preference for food-related odors.

    PubMed

    Tabuchi, E; Ono, T; Uwano, T; Takashima, Y; Kawasaki, M

    1991-01-01

    Preferences for food-related odors and the effects of fasting on those preferences were investigated during rat bar pressing for brief odor presentation. A rat was housed in an equilateral octagonal cage and had free access to food and water, except during fasting. Among 8 food-related odor substances (black pepper, cheese, coffee, milk, nut, peppermint, plum and orange), black pepper, milk and coffee were most preferred, and cheese was least preferred, but even the bar pressing rate for cheese was above the operant level. This data indicates that all 8 odors were preferred by rats, although there were different degrees of preference in individual animals. Fasting substantially increased the rate of bar pressing for odors and changed the odors preferences. This result was probably due to increased search for food and water. Since bar pressing was reinforced by nothing other than odor presentation, the results reveal inherent odor preferences of rats. PMID:1959035

  19. Hypergravity induced prolactin surge in female rats

    NASA Technical Reports Server (NTRS)

    Megory, E.; Oyama, J.

    1985-01-01

    Acute initial exposure to hypergravity (HG) was previously found to induce prolonged diestrous in rats, which was followed by return to normal estrous cycling upon more prolonged exposure to continuous HG. Bromergocryptine was found to prevent this prolonged diestrous. In this study it is found that in female rats 20 h of 3.14 G exposure (D-1 1200 h until D-2 0800 h) can induce prolactin surge at D-2 1600 h. Shorter exposure time (8 h), or exposure during a different part of the estrous cycle (19 h: from D-1 0700 h until D-2 0200 h) could not elicit this prolactin surge. Similar exposure of male rats of HG did not alter significantly their prolactin levels. It is possible that the hypothalamus of male and female rats responds differently to stimulation by HG.

  20. 2011 Desert RATS Sights and Sounds

    NASA Video Gallery

    Watch scenes from the 2011 Desert Research and Technology Studies (RATS) analog field test, as NASA scientists and engineers drive the Space Exploration Vehicle, assemble equipment in the Habitat D...

  1. Corona Discharge Influences Ozone Concentrations Near Rats

    SciTech Connect

    Goheen, Steven C.; Gaither, Kari A.; Anantatmula, Shantha M.; Mong, Gary M.; Sasser, Lyle B.; Lessor, Delbert L.

    2004-02-26

    Ozone is produced by corona discharge in air. Its production is enhanced near grounded water. Whether grounded animals behave like grounded water, producing more ozone was investigated. Rats were exposed to corona discharge in a plastic cage. The concentration of ozone in the gas phase was monitored. The ozone concentration exceeded ambient levels only in the presence of corona discharge and either rats or water. When water or rats were exposed to corona discharge, ozone levels were more than 10 times higher than controls. Ozone levels increased rapidly with applied voltage. There was also a correlation between the distance of the corona needle to the rats and the amount of ozone produced. As the distance increased, ozone production decreased. These results are discussed in relation to the potential exposure of mammals to ozone in the vicinity of corona discharge and electric fields.

  2. RAT SPERM MOTILITY ANALYSIS: METHODOLOGICAL CONSIDERATIONS

    EPA Science Inventory

    The objective of these studies was to optimize conditions for computer assisted sperm analysis (CASA) of rat epididymal spermatozoa. ethodological issues addressed include sample collection technique, sampling region within the epididymis, type of diluent medium used, and sample ...

  3. Rat sperm motility analysis: methodologic considerations

    EPA Science Inventory

    The objective of these studies was to optimize conditions for computer-assisted sperm analysis (CASA) of rat epididymal spermatozoa. Methodologic issues addressed include sample collection technique, sampling region within the epididymis, type of diluent medium used, and sample c...

  4. Anxiolytic Treatment Impairs Helping Behavior in Rats

    PubMed Central

    Ben-Ami Bartal, Inbal; Shan, Haozhe; Molasky, Nora M. R.; Murray, Teresa M.; Williams, Jasper Z.; Decety, Jean; Mason, Peggy

    2016-01-01

    Despite decades of research with humans, the biological mechanisms that motivate an individual to help others remain poorly understood. In order to investigate the roots of pro-sociality in mammals, we established the helping behavior test, a paradigm in which rats are faced with a conspecific trapped in a restrainer that can only be opened from the outside. Over the course of repeated test sessions, rats exposed to a trapped cagemate learn to open the door to the restrainer, thereby helping the trapped rat to escape (Ben-Ami Bartal et al., 2011). The discovery of this natural behavior provides a unique opportunity to probe the motivation of rodent helping behavior, leading to a deeper understanding of biological influences on human pro-sociality. To determine if an affective response motivates door-opening, rats receiving midazolam, a benzodiazepine anxiolytic, were tested in the helping behavior test. Midazolam-treated rats showed less helping behavior than saline-treated rats or rats receiving no injection. Yet, midazolam-treated rats opened a restrainer containing chocolate, highlighting the socially specific effects of the anxiolytic. To determine if midazolam interferes with helping through a sympatholytic effect, the peripherally restricted beta-adrenergic receptor antagonist nadolol was administered; nadolol did not interfere with helping. The corticosterone response of rats exposed to a trapped cagemate was measured and compared to the rats’ subsequent helping behavior. Rats with the greatest corticosterone responses showed the least helping behavior and those with the smallest responses showed the most consistent helping at the shortest latency. These results are discussed in terms of their implications for the interaction between stress and pro-social behavior. Finally, we observed that door-opening appeared to be reinforcing. A novel analytical tool was designed to interrogate the pattern of door-opening for signs that a rat’s behavior on one

  5. Rats and Humans Paying Attention

    PubMed Central

    Demeter, Elise; Sarter, Martin; Lustig, Cindy

    2008-01-01

    Substantial gains have been made on the neurobiology of attention from systems neuroscience work in animal models and human cognitive neuroscience. However, the integration of rodent-based research on the specific neurotransmitter systems that subserve attention with the results from human behavioral and neuroimaging studies has been hampered by the lack of tasks that validly assess attention in both species. To address this issue, an operant sustained attention task that has been extensively used in research on the neurobiology of attention in rats was re-designed and validated for use in humans. Although humans showed better performance overall, the two species showed similar effects of several attention-related variables, including the introduction of distractor-related challenge. This task provides a useful tool for integrative, cross-species research, and may help to determine how specific neurotransmitter systems contribute to the hemodynamic changes observed in human functional neuroimaging experiments. PMID:18999353

  6. Rat growth during chronic centrifugation

    NASA Technical Reports Server (NTRS)

    Pitts, G. C.; Oyama, J.

    1978-01-01

    Female weanling rats were chronically centrifuged at 4.15 G with controls at terrestrial gravity. Samples were sacrificed for body composition studies at 0, 28, 63, 105 and 308 days of centrifugation. The centrifuged group approached a significantly lower mature body mass than the controls (251 and 318g) but the rate of approach was the same in both groups. Retirement to 1G on the 60th day resulted in complete recovery. Among individual components muscle, bone, skin, CNS, heart, kidneys, body water and body fat were changed in the centrifuged group. However, an analysis of the growth of individual components relative to growth of the total fat-free compartment revealed that only skin (which increased in mass) was responding to centrifugation per se.

  7. Sleep Homeostasis in Infant Rats

    PubMed Central

    Blumberg, Mark S.; Middlemis-Brown, Jessica E.; Johnson, Eric D.

    2008-01-01

    Homeostatic regulation is a defining characteristic of sleep but has rarely been examined in infants. This study presents an automated method of sleep deprivation in which 5-day-old rats were shocked whenever the nuchal muscle became atonic. The intensity of shock was always set at the minimal level required to maintain arousal. Deprived pups exhibited rapid increases in sleep pressure, as evidenced by increased attempts to enter sleep and subsequent increases in sensory threshold; this increased sensory threshold was not due to sensory adaptation of peripheral receptors. In addition, myoclonic twitching was suppressed during the 30-min deprivation period, leading to rebound twitching during recovery sleep. These results provide the earliest demonstration of the homeostatic regulation of sleep in an altricial mammal. PMID:15598134

  8. The rat brain hippocampus proteome.

    PubMed

    Fountoulakis, Michael; Tsangaris, George T; Maris, Antony; Lubec, Gert

    2005-05-01

    The hippocampus is crucial in memory storage and retrieval and plays an important role in stress response. In humans, the CA1 area of hippocampus is one of the first brain areas to display pathology in Alzheimer's disease. A comprehensive analysis of the hippocampus proteome has not been accomplished yet. We applied proteomics technologies to construct a two-dimensional database for rat brain hippocampus proteins. Hippocampus samples from eight months old animals were analyzed by two-dimensional electrophoresis and the proteins were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The database comprises 148 different gene products, which are in the majority enzymes, structural proteins and heat shock proteins. It also includes 39 neuron specific gene products. The database may be useful in animal model studies of neurological disorders. PMID:15797529

  9. Tracheal tissue engineering in rats.

    PubMed

    Jungebluth, Philipp; Haag, Johannes C; Sjöqvist, Sebastian; Gustafsson, Ylva; Beltrán Rodríguez, Antonio; Del Gaudio, Costantino; Bianco, Alessandra; Dehnisch, Ivar; Uhlén, Per; Baiguera, Silvia; Lemon, Greg; Lim, Mei Ling; Macchiarini, Paolo

    2014-09-01

    Tissue-engineered tracheal transplants have been successfully performed clinically. However, before becoming a routine clinical procedure, further preclinical studies are necessary to determine the underlying mechanisms of in situ tissue regeneration. Here we describe a protocol using a tissue engineering strategy and orthotopic transplantation of either natural decellularized donor tracheae or artificial electrospun nanofiber scaffolds into a rat model. The protocol includes details regarding how to assess the scaffolds' biomechanical properties and cell viability before implantation. It is a reliable and reproducible model that can be used to investigate the crucial aspects and pathways of in situ tracheal tissue restoration and regeneration. The model can be established in <6 months, and it may also provide a means to investigate cell-surface interactions, cell differentiation and stem cell fate. PMID:25122525

  10. How rats combine temporal cues.

    PubMed

    Guilhardi, Paulo; Keen, Richard; MacInnis, Mika L M; Church, Russell M

    2005-05-31

    The procedures for classical and operant conditioning, and for many timing procedures, involve the delivery of reinforcers that may be related to the time of previous reinforcers and responses, and to the time of onsets and terminations of stimuli. The behavior resulting from such procedures can be described as bouts of responding that occur in some pattern at some rate. A packet theory of timing and conditioning is described that accounts for such behavior under a wide range of procedures. Applications include the food searching by rats in Skinner boxes under conditions of fixed and random reinforcement, brief and sustained stimuli, and several response-food contingencies. The approach is used to describe how multiple cues from reinforcers and stimuli combine to determine the rate and pattern of response bouts. PMID:15845307

  11. Can You Find the Rat Holes?

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Using its rock abrasion tool, otherwise known as 'Rat,' NASA's Mars Exploration Rover Opportunity dotted the slope of 'Endurance Crater' with dimples that give scientists a glimpse into its layered geologic history. This image from the rover's navigation camera, taken on sol 169 (July 15, 2004), highlights the prolific work of the robotic 'rodent.' How many Rat holes can you identify? You will be able to check your answer against an image to be posted soon with all the holes identified.

  12. Finding prefrontal cortex in the rat.

    PubMed

    Leonard, Christiana M

    2016-08-15

    The prefrontal cortex of the rat. I. Cortical projection of the mediodorsal nucleus. II. Efferent connections The cortical projection field of the mediodorsal nucleus of the thalamus (MD) was identified in the rat using the Fink-Heimer silver technique for tracing degenerating fibers. Small stereotaxic lesions confined to MD were followed by terminal degeneration in the dorsal bank of the rhinal sulcus (sulcal cortex) and the medial wall of the hemisphere anterior and dorsal to the genu of the corpus callosum (medial cortex). No degenerating fibers were traced to the convexity of the hemisphere. The cortical formation receiving a projection from MD is of a relatively undifferentiated type which had been previously classified as juxtallocortex. A study of the efferent fiber connections of the rat׳s MD-projection cortex demonstrated some similarities to those of monkey prefrontal cortex. A substantial projection to the pretectal area and deep layers of the superior colliculus originates in medial cortex, a connection previously reported for caudal prefrontal (area 8) cortex in the monkey. Sulcal cortex projects to basal olfactory structures and lateral hypothalamus, as does orbital frontal cortex in the monkey. The rat׳s MD-projection cortex differs from that in the monkey in that it lacks a granular layer and appears to have no prominent direct associations with temporal and juxtahippocampal areas. Furthermore, retrograde degeneration does not appear in the rat thalamus after damage to MD-projection areas, suggesting that the striatum or thalamus receives a proportionally larger share of the MD-projection in this animal than it does in the monkey. Comparative behavioral investigations are in progress to investigate functional differences between granular prefrontal cortex in the primate and the relatively primitive MD-projection cortex in the rat. © 1969. This article is part of a Special Issue entitled SI:50th Anniversary Issue. PMID:26867704

  13. EVOLUTION: Parasites Make Scaredy-Rats Foolhardy.

    PubMed

    Zimmer, C

    2000-07-28

    In the 7 August issue of the Proceedings of the Royal Society of London B, researchers offer a striking demonstration of the ability of some parasites to alter the behavior of their hosts for their own benefit. Rats, the intermediate hosts of the protozoan Toxoplasma gondii, appear to lose their fear of cats, Toxoplasma's final host, when the parasite infects them. By precisely altering rat brains, the parasite potentially increases its chances of completing its life cycle. PMID:17832058

  14. Quantity Discrimination in Domestic Rats, Rattus norvegicus

    PubMed Central

    Cox, Laura; Montrose, V. Tamara

    2016-01-01

    Simple Summary Quantity discrimination involves distinguishing which of two quantities is greater. This discrimination between larger and smaller quantities has only been demonstrated in rats post extensive training. We tested whether domestic rats could perform quantity discrimination without explicit training. We found that rats could distinguish the greater amount in comparisons of 1 vs. 2, 2 vs. 3, 3 vs. 5, 3 vs. 8, 4 vs. 6, and 4 vs. 8. Rats could not distinguish between 3 vs. 4, 4 vs. 5 and 5 vs. 6. We also found that as the ratio between quantities became finer the choice of the larger quantity decreased. We conclude that rats can perform quantity discrimination without extensive training and that their quantity discrimination ability is influenced by the ratio between quantities. Abstract Quantity discrimination is a basic form of numerical competence where an animal distinguishes which of two amounts is greater in size. Whilst quantity discrimination in rats has been investigated via training paradigms, rats’ natural quantity discrimination abilities without explicit training for a desired response have not been explored. This study investigated domestic rats’ ability to perform quantity discrimination. Domestic rats (n = 12) were examined for their ability to distinguish the larger amount under nine quantity comparisons. One-sample t-tests identified a significant preference for the larger quantity in comparisons of 1 vs. 2, 2 vs. 3, 3 vs. 5, 3 vs. 8, 4 vs. 6, and 4 vs. 8. No preference between quantities was found for comparisons of 3 vs. 4, 4 vs. 5 and 5 vs. 6. Overall, this study drew two key conclusions. Firstly, that domestic rats are capable of performing quantity discrimination without extensive training. Secondly, as subjects adhered to Weber’s law, it was concluded that the approximate number system underpins domestic rats’ ability to perform spontaneous quantity discrimination. PMID:27527223

  15. Traumatic arteriogenic erectile dysfunction: a rat model.

    PubMed

    El-Sakka, A; Yen, T S; Lin, C S; Lue, T F

    2001-06-01

    We developed a rat model of traumatic arteriogenic erectile dysfunction (ED) for the study of vasculogenic ED. Bilateral ligation of the internal iliac artery was performed on 30 three-month old male Sprague-Dawley rats as an experimental group. The control group consisted of 12 rats which underwent dissection of the internal iliac artery without ligation. Before their euthanization at 3 days, 7 days, and 1 month (10 rats in the experimental group and four rats in the control group at each time point), erectile function was assessed by electrostimulation of the cavernous nerves. Penile tissues were collected for nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining, trichrome staining, electron microscopy and RT-PCR for transforming growth factor beta (TGF-beta1), insulin like growth factor-I (IGF-I) and fibroblast growth factors (FGF) mRNA expression. Electrostimulation of the cavernous nerves revealed a highly significant declining of the intracavernous pressure after 3 and 7 days. No significant recovery of erectile function was noted at 1 month. Histology showed degeneration of the dorsal nerve fibers in all experimental rats. There was little decrease in the bulk of intracavernous smooth muscle in the experimental rats euthanazed 7 and 30 days. NADPH diaphorase staining revealed a significant decrease in nitric oxide synthase (NOS) containing nerve fibers in the dorsal and intracavernosal nerves in all rats in the experimental group. Electron microscopy showed a variety of changes such as collapse of sinusoids, increased cell debris, fibroblast and myofibroblast loss, intracellular deposition of fat and collagen and fatty degeneration. RT-PCR revealed up-regulation of TGF-beta1 after 3 days but not after 7 days or 1 month. There is no significant difference in IGF-I or FGF expression between the experimental and control group. Bilateral ligation of internal iliac arteries produces a reliable animal model for traumatic arteriogenic ED. Further

  16. Maturation of Jejunum and Ileum in Rats

    PubMed Central

    Younoszai, M. K.; Sapario, R. S.; Laughlin, M.

    1978-01-01

    During osmotic diarrhea, loss of water and electrolytes appears to be greater in infants than in adults. In 2-, 3-, and 7-wk-old rats, we studied net transport of H2O, Na, and Cl, during in vivo perfusion of segments of the jejunum and ileum, from solutions with osmolalities of 300, 375, 500, or 700 mosmol/kg. In the jejunal segments, from the hypertonic solutions net transport of H2O, Na, and Cl was into the lumen and greater in the 2- than 7-wk-old rats. In the ileal segments, transport of water was into the lumen, transport of Na was minimal and variable, whereas transport of Cl was usually out the lumen. In 3-wk-old rats, transport rates were intermediate between those in 2- and 7-wk-old rats. The calculated filtration coefficient (microliters of H2O transported per hour per unit osmolality gradient—lumen-serum—per gram dry weight) of water suggested that the resistance to water flow did not increase with rise in luminal hypertonicity in the jejunum of the 2- and 3-wk-old rats, whereas in jejunum of the 7-wk-old rats and in ileum of rats in all three ages, the resistance to water flow increased with the rise in luminal osmolality. The differences in the transport rates and the resistance to water flow, between segments of the 2-, 3-, and 7-wk-old rats, suggested a maturational phenomenon that appears to continue beyond the 3rd wk of life and could have been due to differences in some physical property of the mucosal membrane. PMID:670394

  17. Hindlimb unweighting affects rat vascular capacitance function

    NASA Technical Reports Server (NTRS)

    Dunbar, S. L.; Tamhidi, L.; Berkowitz, D. E.; Shoukas, A. A.

    2001-01-01

    Microgravity is associated with an impaired stroke volume and, therefore, cardiac output response to orthostatic stress. We hypothesized that a decreased venous filling pressure due to increased venous compliance may be an important contributing factor in this response. We used a constant flow, constant right atrial pressure cardiopulmonary bypass procedure to measure total systemic vascular compliance (C(T)), arterial compliance (C(A)), and venous compliance (C(V)) in seven control and seven 21-day hindlimb unweighted (HLU) rats. These compliance values were calculated under baseline conditions and during an infusion of 0.2 microg*kg(-1)*min(-1) norepinephrine (NE). The change in reservoir volume, which reflects changes in unstressed vascular volume (DeltaV(0)) that occurred upon infusion of NE, was also measured. C(T) and C(V) were larger in HLU rats both at baseline and during the NE infusion (P < 0.05). Infusion of NE decreased C(T) and C(V) by 20% in both HLU and control rats (P < 0.01). C(A) was also significantly decreased in both groups of rats by NE (P < 0.01), but values of C(A) were similar between HLU and control rats both at baseline and during the NE infusion. Additionally, the NE-induced DeltaV(0) was attenuated by 53% in HLU rats compared with control rats (P < 0.05). The larger C(V) and attenuated DeltaV(0) in HLU rats could contribute to a decreased filling pressure during orthostasis and thus may partially underlie the mechanism leading to the exaggerated fall in stroke volume and cardiac output seen in astronauts during an orthostatic stress after exposure to microgravity.

  18. Marginal Hepatectomy in the Rat

    PubMed Central

    Madrahimov, Nodir; Dirsch, Olaf; Broelsch, Christoph; Dahmen, Uta

    2006-01-01

    Objective: Based on the 3-dimensional visualization of vascular supply and drainage, a vessel-oriented resection technique was optimized. The new surgical technique was used to determine the maximal reduction in liver mass enabling a 50% 1-week survival rate. Background Data: Determination of the minimal liver mass is necessary in clinical as well as in experimental liver surgery. In rats, survival seems to depend on the surgical technique applied. Extended hepatectomy with removal of 90% of the liver mass was long regarded as a lethal model. Introduction of a vessel-oriented approach enabled long-term survival in this model. Methods: The lobar and vascular anatomy of rat livers was visualized by plastination of the whole organ, respectively, by corrosion casts of the portal vein, hepatic artery and liver veins. The three-dimensional models were used to extract the underlying anatomic structure. In 90% partial hepatectomy, the liver parenchyma was clamped close to the base of the respective liver lobes (left lateral, median and right, liver lobe). Piercing sutures were placed through the liver parenchyma, so that the stem of portal vein and the accompanying hepatic artery but also the hepatic vein were included. Results: A 1-week survival rate of 100% was achieved after 90% hepatectomy. Extending the procedure to 95% resection by additional removal of the upper caudate lobe led to a 1-week survival rate of 66%; 97% partial hepatectomy, accomplished by additional resection of the lower caudate lobe only leaving the paracaval parts of the liver behind, resulted in 100% lethality within 4 days. Conclusions: Using a anatomically based, vessel-oriented, parenchyma-preserving surgical technique in 95% liver resections led to long-term survival. This represents the maximal reduction of liver mass compatible with survival. PMID:16794393

  19. Calcitonin treatment of immobilization osteoporosis in rats.

    PubMed

    Tuukkanen, J; Jalovaara, P; Väänänen, K

    1991-01-01

    We studied changes in bone mass induced by immobilization and the ability of salmon calcitonin to inhibit immobilization osteoporosis in rat. The bone mass of the immobilized hind leg of rat was compared with the contralateral non-treated leg. Neurectomy and cast immobilization reduced the bone mineral mass to an equal extent. However, the dose-response of calcitonin was different with these immobilization techniques. Calcitonin 15 IU kg-1 administered once daily reduced bone ash weight difference significantly after 2 weeks' neurectomy (P less than 0.001). This had no significant effect on the bone loss induced by cast immobilization, but the dose had to be delivered as two injections given every 12 h. Two weeks' immobilization decreased the incorporation of 45Ca into bones. Calcitonin could not prevent this. However, calcitonin tended to inhibit the overall incorporation of 45Ca into bones in immobilized rats but yet had no effect on 45Ca incorporation in non-immobilized rats. Immobilization decreased serum alkaline phosphatase activity in cast-immobilized animals. Neurectomy did not change serum alkaline phosphatase activity from a sham operation level. The tartrate-resistant acid phosphatase to total acid phosphatase ratio in the serum increased significantly in neurectomized rats and in cast-immobilized calcitonin-treated rats. PMID:2053438

  20. Regulation of brain aromatase activity in rats

    SciTech Connect

    Roselli, C.E.; Ellinwood, W.E.; Resko, J.A.

    1984-01-01

    The distribution and regulation of aromatase activity in the adult rat brain with a sensitive in vitro assay that measures the amount of /sup 3/H/sub 2/O formed during the conversion of (1 beta-/sup 3/H)androstenedione to estrone. The rate of aromatase activity in the hypothalamus-preoptic area (HPOA) was linear with time up to 1 h, and with tissue concentrations up to 5 mgeq/200 microliters incubation mixture. The enzyme demonstrated a pH optimum of 7.4 and an apparent Michaelis-Menten constant (Km) of 0.04 microns. The greatest amount of aromatase activity was found in amygdala and HPOA from intact male rats. The hippocampus, midbrain tegmentum, cerebral cortex, cerebellum, and anterior pituitary all contained negligible enzymatic activity. Castration produced a significant decrease in aromatase activity in the HPOA, but not in the amygdala or cerebral cortex. The HPOAs of male rats contained significantly greater aromatase activity than the HPOAs of female rats. In females, this enzyme activity did not change during the estrous cycle or after ovariectomy. Administration of testosterone to gonadectomized male and female rats significantly enhanced HPOA aromatase activities to levels approximating those found in HPOA from intact males. Therefore, the results suggest that testosterone, or one of its metabolites, is a major steroidal regulator of HPOA aromatase activity in rats.

  1. Colonic Fermentation Promotes Decompression sickness in Rats.

    PubMed

    de Maistre, Sébastien; Vallée, Nicolas; Gempp, Emmanuel; Lambrechts, Kate; Louge, Pierre; Duchamp, Claude; Blatteau, Jean-Eric

    2016-01-01

    Massive bubble formation after diving can lead to decompression sickness (DCS). During dives with hydrogen as a diluent for oxygen, decreasing the body's H2 burden by inoculating hydrogen-metabolizing microbes into the gut reduces the risk of DCS. So we set out to investigate if colonic fermentation leading to endogenous hydrogen production promotes DCS in fasting rats. Four hours before an experimental dive, 93 fasting rats were force-fed, half of them with mannitol and the other half with water. Exhaled hydrogen was measured before and after force-feeding. Following the hyperbaric exposure, we looked for signs of DCS. A higher incidence of DCS was found in rats force-fed with mannitol than in those force-fed with water (80%, [95%CI 56, 94] versus 40%, [95%CI 19, 64], p < 0.01). In rats force-fed with mannitol, metronidazole pretreatment reduced the incidence of DCS (33%, [95%CI 15, 57], p = 0.005) at the same time as it inhibited colonic fermentation (14 ± 35 ppm versus 118 ± 90 ppm, p = 0.0001). Pre-diveingestion of mannitol increased the incidence of DCS in fasting rats when colonic fermentation peaked during the decompression phase. More generally, colonic fermentation in rats on a normal diet could promote DCS through endogenous hydrogen production. PMID:26853722

  2. Glucocorticoid-induced osteoporosis in growing rats.

    PubMed

    Lin, Sien; Huang, Jianping; Zheng, Liang; Liu, Yanzhi; Liu, Guihua; Li, Nan; Wang, Kuixing; Zou, Liyi; Wu, Tie; Qin, Ling; Cui, Liao; Li, Gang

    2014-10-01

    This study evaluated whether growing rats were appropriate animal models of glucocorticoid-induced osteoporosis. The 3-month-old male rats were treated with either vehicle or prednisone acetate at 1.5, 3.0, and 6.0 mg/kg/day by oral gavage, respectively. All rats were injected with tetracycline and calcein before sacrificed for the purpose of double in vivo labeling. Biochemistry, histomorphometry, mechanical test, densitometry, micro-CT, histology, and component analysis were performed. We found that prednisone treatments dose dependently decreased body weight, serum biomarkers, biomechanical markers, bone formation, and bone resorption parameters in both tibial and femoral trabecular bone without trabecular bone loss. We also found that significant bone loss happened in femoral cortical bone in the glucocorticoid-treated rats. The results suggested that prednisone not only inhibited bone formation, but also inhibited bone resorption which resulted in poor bone strength but with no cancellous bone loss in growing rats. These data also suggested that the effects of glucocorticoid on bone metabolism were different between cortical bone and trabecular bone, and different between tibia and femur. Growing rats may be a glucocorticoid-induced osteoporosis animal model when evaluated the effects of drugs upon juvenile patients exposed to GC for a long time. PMID:25086673

  3. Vitamin C modulates lead excretion in rats

    PubMed Central

    Lihm, Hoseob; Kim, Hyun; Chang, Heekyung; Yoon, Myunghee; Lee, Kayoung

    2013-01-01

    Lead, one of the most toxic heavy metals, takes longer time to be excreted from the body than other heavy metals. The purpose of this study is, by measuring lead excretion via urine and feces, to find out the effect of vitamin C in lead chelation. Thirty-six rats were randomly assorted into four groups. All 33 rats except for the control group were administered with lead, before orally administered with different doses of vitamin C per kilogram of body weight. The lead excretion levels in urine and feces as well as the survival rate were then measured for each group. The rats with lead administrations (10/13, 76.9%) with lead administrations only, 10/11 rats (90.9%) with lead administrations and low dose of vitamin C, 9/9 rats (100%) with lead administrations and high dose of vitamin C survived. Among the 29 surviving rats, low vitamin C intake group exhibited higher urinary excretion than the lead only group. The urinary excretion level in high dose vitamin C intakegroup was significantly higher than the lead only group. In addition, fecal lead excretion seemed to be increased in the high dose vitamin C intake group, compared to the group with lead administrations only with statistical significance. Through animal experiment, it was found out that administrating high dose of vitamin C accelerated the excretion of lead in body compared to low dose of vitamin C. PMID:24386596

  4. Hematological Characteristics of the BB Wistar Rat.

    PubMed

    Wright, J R; Yates, A J; Shah, N T; Neff, J C; Covey, D W; Thibert, P

    1983-01-01

    Complete blood counts, differential white blood cell and platelet counts were performed on male and female BB Wistar diabetic rats (BBWd), their nondiabetic siblings (BBWnd) and outbred Wistar rats of the line from which the BB Wistar rats were derived. Most of the observed changes were strain-related (those present in both BBWd and BBWnd but not in control rats) rather than diabetes-related (those in BBWd but neither BBWnd nor control rats) and therefore probably due to the inbreeding process. The BBW strain had significantly lower numbers of white cells and platelets, as well as markedly changed differential white cell counts. Differential counts showed a pattern of lymphopenia, neutrophilia, monocytosis and eosinophilia. It is possible that these white blood cell changes contribute to the increased susceptibility to infection reported for the BBW strain. No significant difference in serum immunoglobulin concentrations was found in any of these three groups of rats. There- fore, hypogammaglobutinemia cannot account for the increased susceptibility to infections, but it is not possible to rule out an abnormality in the distribution of immunoglobulin fractions as an etiological factor. PMID:15311399

  5. Hypergravity modulates behavioral nociceptive responses in rats

    NASA Astrophysics Data System (ADS)

    Kumei, Y.; Shimokawa, R.; Toda, K.; Kawauchi, Y.; Makita, K.; Terasawa, M.; Ohya, K.; Shimokawa, H.

    Hypergravity (2G) exposure elevated the nociceptive threshold (pain suppression) concomitantly with evoked neuronal activity in the hypothalamus. Young Wistar male rats were exposed to 2G by centrifugal rotation for 10 min. Before and after 2G exposure, the nociceptive threshold was measured as the withdrawal reflex by using the von Frey type needle at a total of 8 sites of each rat (nose, four quarters, upper and lower back, tail), and then rats were sacrificed. Fos expression was examined immunohistochemically in the hypothalamic slices of the 2G-treated rats. When rats were exposed to 2G hypergravity, the nociceptive threshold was significantly elevated to approximately 150 to 250% of the 1G baseline control levels in all the examination sites. The 2G hypergravity remarkably induced Fos expression in the paraventricular and arcuate nuclei of the hypothalamus. The analgesic effects of 2G hypergravity were attenuated by naloxone pretreatment. Data indicate that hypergravity induces analgesic effects in rats, mediated through hypothalamic neuronal activity in the endogenous opioid system and hypothalamo-pituitary-adrenal axis.

  6. Peripheral Neuropathy in Rats Exposed to Dichloroacetate

    PubMed Central

    Calcutt, Nigel A.; Lopez, Veronica L.; Bautista, Arjel D.; Mizisin, Leah M.; Torres, Brenda R.; Shroads, Albert L.; Mizisin, Andrew P.; Stacpoole, Peter W.

    2009-01-01

    The use of dichloroacetate (DCA) for treating patients with mitochondrial diseases is limited by the induction of peripheral neuropathy. The mechanisms of DCA-induced neuropathy are not known. Oral DCA treatment (50–500 mg/kg/day for up to 16 weeks) induced tactile allodynia in both juvenile and adult rats; concurrent thermal hypoalgesia developed at higher doses. Both juvenile and adult rats treated with DCA developed nerve conduction slowing that was more pronounced in adult rats. No overt axonal or glial cell abnormalities were identified in peripheral nerves or spinal cord of any DCA-treated rats but morphometric analysis identified a reduction of mean axonal caliber of peripheral nerve myelinated fibers. DCA treatment also caused accumulation of oxidative stress markers in the nerves. These data indicate that behavioral, functional and structural indices of peripheral neuropathy may be induced in both juvenile and adult rats treated with DCA at doses similar to those in clinical use. DCA-induced peripheral neuropathy primarily afflicts axons and involves both metabolic and structural disorders. The DCA-treated rat may provide insight into the pathogenesis of peripheral neuropathy and facilitate development of adjuvant therapeutics to prevent this disorder that currently restricts the clinical use of DCA. PMID:19680144

  7. Thermoregulation in hypergravity-acclimated rats

    NASA Technical Reports Server (NTRS)

    Monson, Conrad B.; Patterson, Susan L.; Horowitz, John M.; Oyama, Jiro

    1989-01-01

    The effect of acclimation to hypergravity on thermoregulatory responses of rats was determined by comparing data on core temperature, T(c), tail temperature, and O2 consumption in rats raised at 1 G (C) and at 2.1 G. It was found that, when C rats were exposed to an ambient temperature of 9 C concurrently with exposure to 2.1 G, the T(c) fell by about 6 C, while in rats acclimated to 2.1 G, the T(c) fell only by 1 C. Results of O2 consumption measurements showed that C rats exposed simultaneously to cold and hypergravity were not activating their thermogenic mechanism sufficiently to prevent a fall in T(c). In other experiments, rats acclimated to either 1 or 2.1 G were found to lack the ability to maintain their T(c) when exposed to a 5.8-G field or when cold-stressed at 1 G for extended times.

  8. Colonic Fermentation Promotes Decompression sickness in Rats

    PubMed Central

    de Maistre, Sébastien; Vallée, Nicolas; Gempp, Emmanuel; Lambrechts, Kate; Louge, Pierre; Duchamp, Claude; Blatteau, Jean-Eric

    2016-01-01

    Massive bubble formation after diving can lead to decompression sickness (DCS). During dives with hydrogen as a diluent for oxygen, decreasing the body’s H2 burden by inoculating hydrogen-metabolizing microbes into the gut reduces the risk of DCS. So we set out to investigate if colonic fermentation leading to endogenous hydrogen production promotes DCS in fasting rats. Four hours before an experimental dive, 93 fasting rats were force-fed, half of them with mannitol and the other half with water. Exhaled hydrogen was measured before and after force-feeding. Following the hyperbaric exposure, we looked for signs of DCS. A higher incidence of DCS was found in rats force-fed with mannitol than in those force-fed with water (80%, [95%CI 56, 94] versus 40%, [95%CI 19, 64], p < 0.01). In rats force-fed with mannitol, metronidazole pretreatment reduced the incidence of DCS (33%, [95%CI 15, 57], p = 0.005) at the same time as it inhibited colonic fermentation (14 ± 35 ppm versus 118 ± 90 ppm, p = 0.0001). Pre-diveingestion of mannitol increased the incidence of DCS in fasting rats when colonic fermentation peaked during the decompression phase. More generally, colonic fermentation in rats on a normal diet could promote DCS through endogenous hydrogen production. PMID:26853722

  9. Transient dehydration of lungs in tail-suspended rats

    NASA Technical Reports Server (NTRS)

    Hargens, A. R.; Steskal, J.; Morey-Holton, E. R.

    1985-01-01

    The fluid balance in the lungs of rats exposed to head-down tilt is examined. Six Munich-Wister rats were suspended for 7 days and 10 Sprague-Dawley rats for 14 days using the technique of Morey (1979). The water contents of the lungs of the suspended and a control group are calculated and compared. The data reveal that the two-days suspended rats had dehydrated lungs; however, the lungs of the 14-day suspended and control group rats were similar. It is noted that the dehydration in the 2-day suspended rats is caused by general dehydration not the head-tilt position.

  10. Hemagglutination by Pasteurellaceae isolated from rodents.

    PubMed

    Boot, R; Thuis, H; Teppema, J S

    1993-06-01

    Pasteurellaceae notably P. pneumotropica, have been associated with severe outbreaks of respiratory disease in several species of rodents. Host-specific parasitism of Pasteurellaceae in rodents has hardly been studied. Since host tropism in many bacteria involves adhesive mechanisms, we examined the hemagglutinating (HA) properties of 44 isolates from different rodent species (mouse (15) rat (8), hamster (9), gerbil (10) and Mastomys (2)). Only 13 mouse isolates and the 2 Mastomys isolates hemagglutinated human (type O Rh+) and canine red blood cells (RBCs). No HA was found using RBCs from 10 other animal species. HA was not inhibited by simple sugars and glycoconjugates, but was completely inhibited by heating of bacterial cells for 10 min at 80 or 100 degrees C, partially inhibited by glutaraldehyde and inhibited in a dose-dependent mode by NaIO4, suggesting the involvement of bacterial polysaccharide structures in the HA process. Enrichment procedures did not reveal the presence of HA- subpopulations in HA+ isolates or the presence of HA+ subpopulations in HA- isolates. Electron microscopy revealed the presence of fimbriae both in HA+ and HA- isolates. A regularly structured (RS) layer was detected on cells of part of the HA+ isolates only. Our results suggest that Pasteurellaceae of mice and Mastomys may be related and differ from isolates isolated from other rodent species. PMID:8219497

  11. Genetic influence on brain catecholamines: high brain norepinephrine in salt-sensitive rats

    SciTech Connect

    Iwai, J; Friedman, R; Tassinari, L

    1980-01-01

    Rats genetically sensitive to salt-induced hypertension evinced higher levels of plasma norepinephrine and epinephrine than rats genetically resistant to hypertension. The hypertension-sensitive rats showed higher hypothalamic norepinephrine and lower epinephrine than resistant rats. In response to a high salt diet, brain stem norepinephrine increased in sensitive rats while resistant rats exhibited a decrease on the same diet.

  12. CHARACTERIZATION OF RESPIRATORY DISEASE IN RATS FOLLOWING NEONATAL INOCULATION WITH A RAT-ADAPTED INFLUENZA VIRUS

    EPA Science Inventory

    Neonatal F344 rats were infected with a rat-adapted influenza virus (RAIV) as a potential model to study the combined effects of early life viral respiratory infection with air pollutant dosimetry and toxic responses, as well as on the development of respiratory disease and incre...

  13. Lassa fever: review of epidemiology and epizootiology

    PubMed Central

    Monath, T. P.

    1975-01-01

    The basic ecology of Lassa fever appears to involve enzootic transmission of virus in commensal populations of a single murine species, Mastomys natalensis. Virus may spill over from the rodent cycle to man by various routes. Secondary spread between humans may occur within domiciliary groups, and persons infected within the community who develop clinical disease may introduce the virus into hospital and begin a cycle of nosocomial infection. Between 1969, when Lassa fever was first described, and June 1975, the disease was recognized on 9 discrete occasions, affecting 114 persons. Over one-third of these infections were acquired by person-to-person spread within hospitals. In only one outbreak (in Sierra Leone) were the majority of cases acquired in the community. Recent observations have indicated hyperendemic disease in eastern Sierra Leone. Cases have occurred in Nigeria, Sierra Leone, and Liberia, and serological evidence exists for activity of the virus elsewhere in West and Central Africa. Seasonal factors appear to play a role in the appearance of human cases. Attack rates have been higher in adults than in children. The source of infection and potential routes of virus transmission in the various epidemics are discussed, and perspectives for future epidemiological research are presented. PMID:782738

  14. Spatial Segregation between Invasive and Native Commensal Rodents in an Urban Environment: A Case Study in Niamey, Niger

    PubMed Central

    Garba, Madougou; Dalecky, Ambroise; Kadaoure, Ibrahima; Kane, Mamadou; Hima, Karmadine; Veran, Sophie; Gagare, Sama; Gauthier, Philippe; Tatard, Caroline; Rossi, Jean-Pierre; Dobigny, Gauthier

    2014-01-01

    Invasive rodents have been responsible for the diffusion worldwide of many zoonotic agents, thus representing major threats for public health. Cities are important hubs for people and goods exchange and are thus expected to play a pivotal role in invasive commensal rodent dissemination. Yet, data about urban rodents' ecology, especially invasive vs. native species interactions, are dramatically scarce. Here, we provide results of an extensive survey of urban rodents conducted in Niamey, Niger, depicting the early stages of rodent bioinvasions within a city. We explore the species-specific spatial distributions throughout the city using contrasted approaches, namely field sampling, co-occurrence analysis, occupancy modelling and indicator geostatistics. We show that (i) two species (i.e. rural-like vs. truly commensal) assemblages can be identified, and that (ii) within commensal rodents, invasive (Rattus rattus and Mus musculus) and native (Mastomys natalensis) species are spatially segregated. Moreover, several pieces of arguments tend to suggest that these exclusive distributions reflect an ongoing native-to-invasive species turn over. The underlying processes as well as the possible consequences for humans are discussed. PMID:25379785

  15. Lassa virus isolates from Mali and the Ivory Coast represent an emerging fifth lineage

    PubMed Central

    Manning, John T.; Forrester, Naomi; Paessler, Slobodan

    2015-01-01

    Previous imported cases of Lassa fever (LF) into the United Kingdom from the Ivory Coast and Mali, as well as the detection of Lassa virus (LASV) among the Mastomys natalensis population within Mali has led to the suggestion that the endemic area for LF is expanding. Initial phylogenetic analyses arrange isolates from Mali and the Ivory Coast separately from the classical lineage IV isolates taken from Sierra Leone, Guinea, and Liberia. The availability of full genome sequences continues to increase, allowing for a more complete phylogenetic comparison of the isolates from Mali and the Ivory Coast to the other existing isolates. In this study, we utilized a Bayesian approach to infer the demographic histories of each LASV isolate for which the full sequence was available. Our results indicate that the isolates from Mali and the Ivory Coast group separately from the isolates of lineage IV, comprising a distinct fifth lineage. The split between lineages IV and V is estimated to have occurred around 200–300 years ago, which coincides with the colonial period of West Africa. PMID:26483768

  16. Effects of Land Use on Plague (Yersinia pestis) Activity in Rodents in Tanzania

    PubMed Central

    McCauley, Douglas J.; Salkeld, Daniel J.; Young, Hillary S.; Makundi, Rhodes; Dirzo, Rodolfo; Eckerlin, Ralph P.; Lambin, Eric F.; Gaffikin, Lynne; Barry, Michele; Helgen, Kristofer M.

    2015-01-01

    Understanding the effects of land-use change on zoonotic disease risk is a pressing global health concern. Here, we compare prevalence of Yersinia pestis, the etiologic agent of plague, in rodents across two land-use types—agricultural and conserved—in northern Tanzania. Estimated abundance of seropositive rodents nearly doubled in agricultural sites compared with conserved sites. This relationship between land-use type and abundance of seropositive rodents is likely mediated by changes in rodent and flea community composition, particularly via an increase in the abundance of the commensal species, Mastomys natalensis, in agricultural habitats. There was mixed support for rodent species diversity negatively impacting Y. pestis seroprevalence. Together, these results suggest that land-use change could affect the risk of local transmission of plague, and raise critical questions about transmission dynamics at the interface of conserved and agricultural habitats. These findings emphasize the importance of understanding disease ecology in the context of rapidly proceeding landscape change. PMID:25711606

  17. Effects of land use on plague (Yersinia pestis) activity in rodents in Tanzania.

    PubMed

    McCauley, Douglas J; Salkeld, Daniel J; Young, Hillary S; Makundi, Rhodes; Dirzo, Rodolfo; Eckerlin, Ralph P; Lambin, Eric F; Gaffikin, Lynne; Barry, Michele; Helgen, Kristofer M

    2015-04-01

    Understanding the effects of land-use change on zoonotic disease risk is a pressing global health concern. Here, we compare prevalence of Yersinia pestis, the etiologic agent of plague, in rodents across two land-use types-agricultural and conserved-in northern Tanzania. Estimated abundance of seropositive rodents nearly doubled in agricultural sites compared with conserved sites. This relationship between land-use type and abundance of seropositive rodents is likely mediated by changes in rodent and flea community composition, particularly via an increase in the abundance of the commensal species, Mastomys natalensis, in agricultural habitats. There was mixed support for rodent species diversity negatively impacting Y. pestis seroprevalence. Together, these results suggest that land-use change could affect the risk of local transmission of plague, and raise critical questions about transmission dynamics at the interface of conserved and agricultural habitats. These findings emphasize the importance of understanding disease ecology in the context of rapidly proceeding landscape change. PMID:25711606

  18. Novel Arenavirus Sequences in Hylomyscus sp. and Mus (Nannomys) setulosus from Côte d'Ivoire: Implications for Evolution of Arenaviruses in Africa

    PubMed Central

    Kouassi, Stéphane K.; Fichet-Calvet, Elisabeth; Becker-Ziaja, Beate; Rieger, Toni; Ölschläger, Stephan; Dosso, Hernri; Denys, Christiane; ter Meulen, Jan; Akoua-Koffi, Chantal; Günther, Stephan

    2011-01-01

    This study aimed to identify new arenaviruses and gather insights in the evolution of arenaviruses in Africa. During 2003 through 2005, 1,228 small mammals representing 14 different genera were trapped in 9 villages in south, east, and middle west of Côte d'Ivoire. Specimens were screened by pan-Old World arenavirus RT-PCRs targeting S and L RNA segments as well as immunofluorescence assay. Sequences of two novel tentative species of the family Arenaviridae, Menekre and Gbagroube virus, were detected in Hylomyscus sp. and Mus (Nannomys) setulosus, respectively. Arenavirus infection of Mus (Nannomys) setulosus was also demonstrated by serological testing. Lassa virus was not found, although 60% of the captured animals were Mastomys natalensis. Complete S RNA and partial L RNA sequences of the novel viruses were recovered from the rodent specimens and subjected to phylogenetic analysis. Gbagroube virus is a closely related sister taxon of Lassa virus, while Menekre virus clusters with the Ippy/Mobala/Mopeia virus complex. Reconstruction of possible virus–host co-phylogeny scenarios suggests that, within the African continent, signatures of co-evolution might have been obliterated by multiple host-switching events. PMID:21695269

  19. Imported Lassa fever--New Jersey, 2004.

    PubMed

    2004-10-01

    Lassa fever is an acute viral illness caused by Lassa virus, which is hosted by rodents in the Mastomys natalensis species complex and rarely imported to countries outside of those areas in Africa where the disease is endemic. Lassa fever is characterized by fever, muscle aches, sore throat, nausea, vomiting, and chest and abdominal pain. Approximately 15%-20% of patients hospitalized for Lassa fever die from the illness; however, approximately 80% of human infections with Lassa virus are mild or asymptomatic, and 1% of infections overall result in death. On August 28, 2004, a man aged 38 years residing in New Jersey died from Lassa fever after returning from travel to West Africa. This report summarizes the clinical and epidemiologic investigations conducted by federal, state, and local public health agencies. The findings illustrate the need for clinicians and public health officials to remain alert to emerging infectious diseases and to institute appropriate measures to promptly identify and limit spread of unusual pathogens. PMID:15457145

  20. Advanced vaccine candidates for Lassa fever.

    PubMed

    Lukashevich, Igor S

    2012-11-01

    Lassa virus (LASV) is the most prominent human pathogen of the Arenaviridae. The virus is transmitted to humans by a rodent reservoir, Mastomys natalensis, and is capable of causing lethal Lassa Fever (LF). LASV has the highest human impact of any of the viral hemorrhagic fevers (with the exception of Dengue Fever) with an estimated several hundred thousand infections annually, resulting in thousands of deaths in Western Africa. The sizeable disease burden, numerous imported cases of LF in non-endemic countries, and the possibility that LASV can be used as an agent of biological warfare make a strong case for vaccine development. Presently there is no licensed vaccine against LF or approved treatment. Recently, several promising vaccine candidates have been developed which can potentially target different groups at risk. The purpose of this manuscript is to review the LASV pathogenesis and immune mechanisms involved in protection. The current status of pre-clinical development of the advanced vaccine candidates that have been tested in non-human primates will be discussed. Major scientific, manufacturing, and regulatory challenges will also be considered. PMID:23202493

  1. Advanced Vaccine Candidates for Lassa Fever

    PubMed Central

    Lukashevich, Igor S.

    2012-01-01

    Lassa virus (LASV) is the most prominent human pathogen of the Arenaviridae. The virus is transmitted to humans by a rodent reservoir, Mastomys natalensis, and is capable of causing lethal Lassa Fever (LF). LASV has the highest human impact of any of the viral hemorrhagic fevers (with the exception of Dengue Fever) with an estimated several hundred thousand infections annually, resulting in thousands of deaths in Western Africa. The sizeable disease burden, numerous imported cases of LF in non-endemic countries, and the possibility that LASV can be used as an agent of biological warfare make a strong case for vaccine development. Presently there is no licensed vaccine against LF or approved treatment. Recently, several promising vaccine candidates have been developed which can potentially target different groups at risk. The purpose of this manuscript is to review the LASV pathogenesis and immune mechanisms involved in protection. The current status of pre-clinical development of the advanced vaccine candidates that have been tested in non-human primates will be discussed. Major scientific, manufacturing, and regulatory challenges will also be considered. PMID:23202493

  2. Mapping the zoonotic niche of Lassa fever in Africa

    PubMed Central

    Mylne, Adrian Q. N.; Pigott, David M.; Longbottom, Joshua; Shearer, Freya; Duda, Kirsten A.; Messina, Jane P.; Weiss, Daniel J.; Moyes, Catherine L.; Golding, Nick; Hay, Simon I.

    2015-01-01

    Background Lassa fever is a viral haemorrhagic illness responsible for disease outbreaks across West Africa. It is a zoonosis, with the primary reservoir species identified as the Natal multimammate mouse, Mastomys natalensis. The host is distributed across sub-Saharan Africa while the virus' range appears to be restricted to West Africa. The majority of infections result from interactions between the animal reservoir and human populations, although secondary transmission between humans can occur, particularly in hospital settings. Methods Using a species distribution model, the locations of confirmed human and animal infections with Lassa virus (LASV) were used to generate a probabilistic surface of zoonotic transmission potential across sub-Saharan Africa. Results Our results predict that 37.7 million people in 14 countries, across much of West Africa, live in areas where conditions are suitable for zoonotic transmission of LASV. Four of these countries, where at-risk populations are predicted, have yet to report any cases of Lassa fever. Conclusions These maps act as a spatial guide for future surveillance activities to better characterise the geographical distribution of the disease and understand the anthropological, virological and zoological interactions necessary for viral transmission. Combining this zoonotic niche map with detailed patient travel histories can aid differential diagnoses of febrile illnesses, enabling a more rapid response in providing care and reducing the risk of onward transmission. PMID:26085474

  3. Lassa fever in West African sub-region: an overview.

    PubMed

    Ogbu, O; Ajuluchukwu, E; Uneke, C J

    2007-03-01

    Lassa fever is an acute viral zoonotic illness caused by Lassa virus, an arenavirus known to be responsible for a severe haemorrhagic fever characterised by fever, muscle aches, sore throat, nausea, vomiting and, chest and abdominal pain. The virus exhibits persistent, asymptomatic infection with profuse urinary virus excretion in the ubiquitous rodent vector, Mastomys natalensis. Lassa fever is endemic in West Africa and has been reported from Sierra Leone, Guinea, Liberia, and Nigeria. Some studies indicate that 300,000 to 500,000 cases of Lassa fever and 5000 deaths occur yearly across West Africa. Studies reported in English, that investigated Lassa fever with reference to West Africa were identified using the Medline Entrez-PubMed search and were used for this review. The scarcity of resources available for health care delivery system and the political instability that characterise the West African countries would continue to impede efforts for the control of Lassa fever in the sub-region. There is need for adequate training of health care workers regarding diagnostics, intensive care of patients under isolation, contact tracing, adequate precautionary measures in handling infectious laboratory specimens, control of the vector as well as care and disposal of infectious waste. PMID:17378212

  4. Sequence homology between RNAs encoding rat alpha-fetoprotein and rat serum albumin.

    PubMed Central

    Jagodzinski, L L; Sargent, T D; Yang, M; Glackin, C; Bonner, J

    1981-01-01

    We have determined the sequences of the recombinant DNA inserts of three bacterial plasmid cDNA clones containing most of the rat alpha a-fetoprotein mRNA. The resultant nucleotide sequence of alpha-fetoprotein was exhaustively compared to the nucleotide sequence of the mRNA encoding rat serum albumin. These two mRNAs have extensive homology (50%) throughout and the same intron locations. The amino acid sequence of rat alpha-fetoprotein has been deduced from the nucleotide sequence, and its comparison to rat serum albumin's amino acid sequence reveals a 34% homology. The regularly spaced positions of the cysteines found in serum albumin are conserved in rat alpha-fetoprotein, indicating that these two proteins may have a similar secondary folding structure. These homologies indicate that alpha-fetoprotein and serum albumin were derived by duplication of a common ancestral gene and constitute a gene family. PMID:6167988

  5. Social Structure Predicts Genital Morphology in African Mole-Rats

    PubMed Central

    Seney, Marianne L.; Kelly, Diane A.; Goldman, Bruce D.; Šumbera, Radim; Forger, Nancy G.

    2009-01-01

    Background African mole-rats (Bathyergidae, Rodentia) exhibit a wide range of social structures, from solitary to eusocial. We previously found a lack of sex differences in the external genitalia and morphology of the perineal muscles associated with the phallus in the eusocial naked mole-rat. This was quite surprising, as the external genitalia and perineal muscles are sexually dimorphic in all other mammals examined. We hypothesized that the lack of sex differences in naked mole-rats might be related to their unusual social structure. Methodology/Principal Findings We compared the genitalia and perineal muscles in three African mole-rat species: the naked mole-rat, the solitary silvery mole-rat, and the Damaraland mole-rat, a species considered to be eusocial, but with less reproductive skew than naked mole-rats. Our findings support a relationship between social structure, mating system, and sexual differentiation. Naked mole-rats lack sex differences in genitalia and perineal morphology, silvery mole-rats exhibit sex differences, and Damaraland mole-rats are intermediate. Conclusions/Significance The lack of sex differences in naked mole-rats is not an attribute of all African mole-rats, but appears to have evolved in relation to their unusual social structure and reproductive biology. PMID:19829697

  6. Intermittent heat exposure and thirst in rats.

    PubMed

    Barney, Christopher C; Kuhrt, David M

    2016-04-01

    Adequate water intake, supporting both cardiovascular function and evaporative cooling, is a critical factor in mitigating the effects of heat waves, which are expected to increase with global warming. However, the regulation of water intake during periods of intermittent heat exposure is not well understood. In this study, the effects of access to water or no access during intermittent heat exposure were assessed using male Sprague-Dawley rats exposed to 37.5°C for 4 h/day. After 7 days of intermittent heat exposure, reductions in evaporative water loss were observed in all animals and reductions in water intake following heat exposure occurred as the days of heat exposure increased. Rats that were not allowed water during the 7 days of exposure had decreased rehydration levels, however, rats allowed access to water increased water intake during exposure and exhibited higher overall rehydration levels over the same time period. Peripheral administration of angiotensinII, mimicking activation of volemic thirst, or hypertonic saline solution, activating intracellular thirst, did not result in alteration of water intake in rats exposed to heat with access to water compared to control rats. In contrast, rats exposed to heat without access to water had reduced water intake after administration of hypertonic saline and increased water intake after administration of angiotensinIIcompared to control rats. These experiments demonstrate that thirst responses to intermittent heat exposure are altered by providing water during heat exposure and that intermittent heat exposure without access to water alters drinking responses to both intracellular and extracellular thirst challenges. PMID:27095836

  7. Effect of simulated weightlessness on energy metabolism in the rat

    NASA Technical Reports Server (NTRS)

    Jordan, J. P.; Sykes, H. A.; Crownover, J. C.; Schatte, C. L.; Simmons, J. B., II; Jordan, D. P.

    1982-01-01

    Results of measurements of food uptake and body weight changes occurring in rats suspended from a harness so that the antigravity muscles were not used for locomotion are presented. The rats were tested in pairs, with both in a harness but only one suspended off its hind legs; this section lasted 7 days. A second phase of the experiment involved feeding the nonsuspended rat the same amount of food the experimental rat had consumed the previous day. All rats experienced decreased in body weight and food intake in the first stage, while in the second stage the suspended rat lost more weight. The total oxygen uptake, CO2 output, and rate of C-14O2 production were depressed in the suspended rats, then returned to normal levels once the rats were back on the ground. It is concluded that the gross metabolic processes are unaffected by simulated weightlessness.

  8. Neighborhood Rats as Depressing as Crime, Study Finds

    MedlinePlus

    ... nih.gov/medlineplus/news/fullstory_157831.html Neighborhood Rats as Depressing as Crime, Study Finds Research suggests ... 17, 2016 THURSDAY, March 17, 2016 (HealthDay News) -- Rat infestations may harm the mental health of people ...

  9. High prevalence of rat hepatitis E virus in wild rats in China.

    PubMed

    Li, Wei; Guan, Dawei; Su, Juan; Takeda, Naokazu; Wakita, Takaji; Li, Tian-Cheng; Ke, Chang Wen

    2013-08-30

    Serum samples from a total of 713 wild rats captured in Zhanjiang city in China from December 2011 to September 2012 were investigated for the prevalence of rat hepatitis E virus (HEV) by exploring rat HEV-specific antibodies and RNA. By an ELISA based on recombinant rat HEV-like particles (HEV-LPs), 23.3% (166/713) of the rats were positive for anti-HEV IgG, and 8.3% (59/713) were positive for anti-HEV IgM. The IgG-positive rates in Rattus norvegicus, Bandicota indica, Rattus flavipectus, Rattus rattoides losea, and Rattus rattus hainanus, were 27.8% (64/230), 23.0% (40/174), 19.9% (34/171), 21.5% (26/121), and 11.8% (2/17), while the IgM-positive rates were 8.3% (19/230), 6.9% (12/174), 8.2% (14/171), 10.7% (13/121), and 5.9% (1/17), respectively. The IgG-positive rate of the rats captured in rural areas, 24.1% (84/348), was higher than that in the central area of Zhanjiang city, 15.1% (32/212). The highest IgG-positive rates, as high as 45.3% (39/86), were detected in wild rats trapped in the garbage dump. Twelve of the 59 IgM-positive serum samples were positive for HEV RNA, which was detected in all of the wild rat species except R. rattus hainanus. A phylogenetic analysis of the partial genome of rat HEV ORF1 indicated that all of the 12 HEV strains belong to rat HEV, and no other genotype HEV were detected. The rat HEV from Zhangjiang city could be classified into three separated clusters, suggesting that the infection due to rat HEV with a variety of genome entities occurs extensively among wild rats in China. PMID:23623690

  10. Urea synthesis in rats fed diet containing kidney beans.

    PubMed

    Scislowski, P W; Grant, G; Harris, I; Pickard, K; Pusztai, A

    1992-10-01

    When rats were fed a diet containing kidney bean (Phaesolus vulgaris) urea excretion was increased 3-5 fold. Isolated liver mitochondria from rats fed the kidney bean diet produced 40% more citrulline in the presence of arginine than mitochondria isolated from control rats. Mitochondrial activities of urea cycle enzymes and N-acetylglutamate synthetase were similar in animals fed diets containing kidney bean or lactalbumin. The possible mechanisms causing acute urea production in rats fed with kidney bean are discussed. PMID:1445392

  11. An experimental task to examine the mirror system in rats

    PubMed Central

    Takano, Yuji; Ukezono, Masatoshi

    2014-01-01

    The mirror system in the brain is considered to be a neural basis of sociality, but previous studies have been limited to primates. Here we report an experimental task to examine the mirror system in rats. We show that a rat could reach to a pellet and grasp and eat it in front of another rat that was observing the reaching, which indicates that the task will enable us to start exploring the rat mirror system. PMID:25323637

  12. Nigella Sativa reverses osteoporosis in ovariectomized rats

    PubMed Central

    2014-01-01

    Background Osteoporosis poses a significant public health issue. It is a skeletal disorder characterized by compromised bone strength that predisposes to increased risk of fracture. There is a direct relationship between the lack of estrogen after menopause and the development of osteoporosis. About 33% of women over 50 will experience bone fractures as a result of osteoporosis. Nigella Sativa (NS) has been shown to have beneficial effects on bone and joint diseases. The present study was conducted to elucidate the protective effect of Nigella Sativa on osteoporosis produced by ovariectomy in rats. Methods Female Wistar rats aged 12–14 months were divided into three groups: sham-operated control (SHAM), ovariectomized (OVX), and ovariectomized supplemented with nigella sativa (OVX-NS) orally for 12 weeks; 4 weeks before ovariectomy and 8 weeks after. After 12 weeks, plasma levels of calcium (Ca+2), phosphorous (Pi), alkaline phosphatase (ALP), amino terminal collagen type 1 telopeptide, malondialdehyde (MDA), nitrates, nitric oxide surrogate, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were measured. Histological examination of the liver and the tibia was conducted. Histomorphometric analysis of the tibia was also performed. Results OVX rats showed significant decrease in plasma Ca+2, accompanied by a significant increase in plasma ALP, amino terminal collagen type 1 telopeptide, MDA, nitrates, TNF-α and IL-6. These changes were reversed by NS supplementation in OVX-NS group to be near SHAM levels. Histological examination of the tibias revealed discontinuous eroded bone trabeculae with widened bone marrow spaces in OVX rats accompanied by a significant decrease in both cortical and trabecular bone thickness compared to Sham rats. These parameters were markedly reversed in OVX-NS rats. Histological examination of the liver showed mononuclear cellular infiltration and congestion of blood vessels at the portal area in OVX rats which were not found

  13. Opioids and rat erythrocyte deformability.

    PubMed

    Rhoads, D L; Wei, L X; Lin, E T; Rezvani, A; Way, E L

    1986-01-01

    In previous studies from this laboratory, it was noted that opioids in vitro reduced human red blood cell deformability. The effect was found to be dose-dependent, naloxone reversible and preferentially selective kappa ligands exhibited the highest potency. To extend these findings studies were carried out using rat erythrocytes. The time required for erythrocytes to pass through a 5.0 um pore membrane was determined and used as an index of deformability. Opioids added in vitro produced inhibition of deformability in a dose-dependent, naloxone reversible manner. Injecting naive animals with morphine or nalbuphine also produced dose related reductions in red cell deformability. The degree of inhibition produced by nalbuphine correlated well with its plasma concentrations as measured by high performance liquid chromatography (HPLC). Chronic morphine treatment by pellet implantation resulted in the development of tolerance as evidenced by a loss in the ability of morphine in vitro to inhibit red cell deformability. Addition of naloxone resulted in a decrease in filtration time. Thus, the data confirm and extend previous findings on human red blood cells. In as much as previous data from this laboratory demonstrated that opioids inhibit calcium flux from erythrocytes by inhibiting calcium-ATPase and calcium efflux is necessary for normal deformability, it is concluded that opioids act to reduce red cell deformability by inhibition of the calcium pump. PMID:3123933

  14. Pharmacokinetics of azithromycin in rats and dogs.

    PubMed

    Shepard, R M; Falkner, F C

    1990-01-01

    After intravenous or oral administration to rats and dogs, azithromycin was rapidly distributed into the tissues, where concentrations frequently exceeded those in serum by 100-fold or more within 24 h of a single dose. Tissue concentrations were proportional to the dose following single administrations of 10 to 40 mg/kg in rats and dogs. Tissue concentrations were higher after multiple dosing and became greater as the dose was increased from 10 to 40 mg/kg. Elimination half-lives were similar in most tissues and were about 40 h in rats after seven doses of 20 mg/kg and about 90 h in dogs after five doses of 30 mg/kg. Serum concentrations declined in a multi-exponential manner, reflecting initial rapid distribution into tissues and then slow return to serum from tissues. Azithromycin had good oral bioavailability in rats and dogs (46% and 97%, respectively). Rapid uptake of azithromycin by tissues from serum and slow redistribution from tissues to serum are apparently factors governing the pharmacokinetics of azithromycin in rats and dogs. Serum concentrations do not reflect the availability of azithromycin in tissues. PMID:2154438

  15. Cardiopulmonary Changes with Moderate Decompression in Rats

    NASA Technical Reports Server (NTRS)

    Robinson, R.; Little, T.; Doursout, M.-F.; Butler, B. D.; Chelly, J. E.

    1996-01-01

    Sprague-Dawley rats were compressed to 616 kPa for 120 min then decompressed at 38 kPa/min to assess the cardiovascular and pulmonary responses to moderate decompression stress. In one series of experiments the rats were chronically instrumented with Doppler ultrasonic probes for simultaneous measurement of blood pressure, cardiac output, heart rate, left and right ventricular wall thickening fraction, and venous bubble detection. Data were collected at base-line, throughout the compression/decompression protocol, and for 120 min post decompression. In a second series of experiments the pulmonary responses to the decompression protocol were evaluated in non-instrumented rats. Analyses included blood gases, pleural and bronchoalveolar lavage (BAL) protein and hemoglobin concentration, pulmonary edema, BAL and lung tissue phospholipids, lung compliance, and cell counts. Venous bubbles were directly observed in 90% of the rats where immediate post-decompression autopsy was performed and in 37% using implanted Doppler monitors. Cardiac output, stroke volume, and right ventricular wall thickening fractions were significantly decreased post decompression, whereas systemic vascular resistance was increased suggesting a decrease in venous return. BAL Hb and total protein levels were increased 0 and 60 min post decompression, pleural and plasma levels were unchanged. BAL white blood cells and neutrophil percentages were increased 0 and 60 min post decompression and pulmonary edema was detected. Venous bubbles produced with moderate decompression profiles give detectable cardiovascular and pulmonary responses in the rat.

  16. Radioimmunoimaging of pneumocystis carinii infection in rats

    SciTech Connect

    Vallabhajosula, S.; Shane, L.B.; Goldsmith, S.J.; Lipszyc, H.; Walzer, P.

    1984-01-01

    Pneumocystis carinil pneumonia (PCP) is seen in patients with impaired immunity due to chemotherapeutic suppression or to a primary disorder, congenital or AIDS. Although radiogallium imaging has been helpful in the workup of PCP, it is non-specific. Since there is no early specific non-invasive method to diagnose PCP, the authors are developing an imaging technique using radiolabeled antibodies. Fulminant PCP was induced in rats by injecting cortisone, 20mg 2-3 times/wk for 8 wks. PC cells isolated from rat lung were injected into rabbits. The antiserum thus derived was separated and purified using Protein-A bound sepharose column with identification of IgG by polyacrylamide gel electrophoresis. Both rabbit antipneumocystis antibodies and purified IgG(Sigma) were iodinated with I-131 to a high specific activity (3-5..mu..Ci/ug) using a lactoperoxidase method. /sup 131/I-labeled specific and non-specific IgG were injected into rats with PC infection and imaged with an Anger camera. After sacrifice, I-131 activity/gram tissue (lung, liver, heart) was determined and expressed as organ ratios. An increased uptake of specific antibody in lungs of rats with PCP was demonstrated by organ counting and imaging. This increase was not seen in normal controls or rats injected with non-specific IgG. These data provide a basis for radioimmunoimaging of infectious diseases.

  17. Opiates and cerebral functional activity in rats

    SciTech Connect

    Trusk, T.C.

    1986-01-01

    Cerebral activity was measured using the free-fatty acid (1-/sup 14/C) octanoate as a fast functional tracer in conscious, unrestrained rats 5 minutes after intravenous injection of heroin, cocaine or saline vehicle. Regional changes of octanoate labeling density in the autoradiograms relative to saline-injected animals were used to determine the functional activity effects of each drug. Heroin and cocaine each produced a distinctive pattern of activity increases and suppression throughout the rat brain. Similar regional changes induced by both drugs were found in limbic brain regions implicated in drug reinforcement. Labeled octanoate autoradiography was used to measure the cerebral functional response to a tone that had previously been paired to heroin injections. Rats were trained in groups of three consisting of one heroin self-administration animal, and two animals receiving yoked infusion of heroin or saline. A tone was paired with each infusion during training. Behavioral experiments in similarly trained rats demonstrated that these training conditions impart secondary reinforcing properties to the tone in animals previously self-administering heroin, while the tone remains behaviorally neutral in yoked-infusion rats. Cerebral functional activity was measured during presentation of the tone without drug infusion. Octanoate labeling density changed in fifteen brain areas in response to the tone previously paired to heroin without response contingency. Labeling density was significantly modified in sixteen regions as a result of previously pairing the tone to response-contingent heroin infusions.

  18. Glutathione system in young spontaneously hypertensive rats.

    PubMed

    Lee, S K; Arunkumar, Sundaram; Sirajudeen, K N S; Singh, H J

    2010-12-01

    Glutathione (GSH) forms a part of the antioxidant system that plays a vital role in preventing oxidative stress, and an imbalance in the oxidant/antioxidant system has been linked to the pathogenesis of hypertension. The aim of this study was to investigate the status of the GSH system in the kidney of spontaneously hypertensive rats (SHR). Components of the GSH system, including glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), and total GSH content, were measured in the kidneys of 4, 6, 8, 12, and 16 weeks old SHR and Wistar-Kyoto (WKY) rats. Systolic blood pressure of SHR was significantly higher from the age of 6 weeks onwards compared with age-matched WKY rats. GPx activity in the SHR was significantly lower from the age of 8 weeks onwards when compared to that in age-matched WKY rats. No significant differences were evident in the GPx-1 protein abundance, and its relative mRNA levels, GR, GST activity, and total GSH content between SHR and age-matched WKY rats. The lower GPx activity suggests of an impairment of the GSH system in the SHR, which might be due to an abnormality in its protein rather than non-availability of a cofactor. Its role in the development of hypertension in SHR however remains unclear. PMID:20680541

  19. Group G streptococcal lymphadenitis in rats.

    PubMed

    Corning, B F; Murphy, J C; Fox, J G

    1991-12-01

    Group G streptococci which have been isolated from the oral flora of rats are also normal inhabitants of the human skin, oropharynx, gastrointestinal tract, and female genital tract. This group of streptococci can cause a wide variety of clinical diseases in humans, including septicemia, pharyngitis, endocarditis, pneumonia, and meningitis. Ten days after oral gavage with 7,12-dimethylbenz[a]anthracene, 12 of 22 two-month-old, female, outbred, viral-antibody-free rats presented with red ocular and nasal discharges and marked swelling of the cervical region. Various degrees of firm, nonpitting edema in the region of the cervical lymph nodes and salivary glands as well as pale mucous membranes and dehydration were observed. Pure cultures of beta-hemolytic streptococci were obtained from the cervical lymph nodes of three rats that were necropsied. A rapid latex test system identified the isolates to have group G-specific antigen. These streptococcal isolates fermented trehalose and lactose but not sorbitol and inulin and did not hydrolize sodium hippurate or bile esculin. A Voges-Proskauer test was negative for all six isolates. Serologic tests to detect the presence of immunoglobulin G antibody to rat viral pathogens and Mycoplasma pulmonis were negative. Histopathologic changes included acute necrotizing inflammation of the cervical lymph nodes with multiple large colonies of coccoid bacteria at the perimeter of the necrotiz zone. To our knowledge, this is the first report of naturally occurring disease attributed to group G streptococci in rats. PMID:1757539

  20. EVALUATION OF PERFLUOROOCTANE SULFONATE (PFOS) IN THE RAT BRAIN

    EPA Science Inventory

    This study examined whether there is a differential distribution of PFOS within the brain, and compares adult rats with neonatal rats at an age when formation of the blood-brain barrier is not yet complete (postnatal day 7). Male and female Sprague-Dawley rats (60-70 day old, 4/...

  1. On the rat model of human osteopenias and osteoporoses

    NASA Technical Reports Server (NTRS)

    Frost, Harold M.; Jee, Webster S. S.

    1992-01-01

    The idea that rats cannot model human osteopenias errs. The same mechanisms control gains in bone mass (longitudinal bone growth and modeling drifts) and losses (BMU-based remodeling), in young and aged rats and humans. Furthermore, they respond similarly in rats and man to mechanical influences, hormones, drugs and other agents.

  2. Estimation of restraint stress in rats using salivary amylase activity.

    PubMed

    Matsuura, Tetsuya; Takimura, Ryo; Yamaguchi, Masaki; Ichinose, Mitsuyuki

    2012-09-01

    The rat is an ideal model animal for studying physical and psychological stresses. Recent human studies have shown that salivary amylase activity is a useful biomarker of stress in our social life. To estimate the usefulness of amylase activity as a biomarker of stress in rats, we analyzed changes in physiological parameters including amylase activity and anatomical variables, which were induced by a mild restraint of paws (10 min, 3 times/week, 9 weeks). The quantities of food and water intake and excretion amount of the stress rats were smaller than those of the control rats during the experimental period (5-13 weeks). The body weight of the stress rats decreased compared with that of the control rats. Moreover, the enlargement of the adrenal gland was confirmed in the stress rats, indicating that the mild restraint caused a chronic stress response. The amylase activities of the stress rats were significantly greater than those of the control rats at 5 weeks of age. However, the amylase activity of the stress rats decreased compared with that of the control rats after 6 weeks of age. These results indicate that amylase activity is increased by acute stress and reduced by chronic stress, which is caused by repeated restraint stress. In conclusion, amylase activity is a useful biomarker of acute and chronic stresses in rats. PMID:22753135

  3. Deficits in reproductive behaviour in septally lesioned female rats.

    PubMed

    Gogate, M G; Brid, S V; Wingkar, K C

    1991-12-01

    Estrous cycle and sexual behaviour were studied in septally lesioned female albino Wistar rats. In lesioned rats the vaginal smears showed continuous diestrus and the females failed to exhibit sexual receptivity during the postoperative period. Ovarian and uterine weights in lesioned rats were also significantly decreased. The results suggest that the septal nuclei exert a modulatory influence on female sexual behaviour. PMID:1816101

  4. Fetal rat pancreas transplantation in BB rats: immunohistochemical and functional evaluation.

    PubMed

    Yderstraede, K B; Starklint, H; Steinbruchel, D; Jørgensen, T W; Gotfredsen, C F

    1993-01-01

    Spontaneously diabetic BB/Wor rats received either a syngeneic fetal pancreas transplant or adult islets. In the former, 4-8 fetal pancreases were transplanted, and in the latter, 3-5000 islets. Transplantation was performed by transferring a blood clot containing the pancreases or islets to the renal subcapsular space. Insulin therapy was undertaken postoperatively, except in one experiment with adult islets. Of the fetal pancreas transplanted BB rats, 52% became normoglycaemic, and 21% remained so throughout an observation period of 10 months. Nephrectomy caused a prompt return of diabetes. The histological appearance of the grafts transplanted to the diabetic animals closely resembled that of grafts transplanted to normal rats in a parallel series. For comparison a group of BB rats received a syngeneic transplant of isolated adult islets from WF rats or BBW rats. Following adult islet transplantation, 5 out of 6 animals became hyperglycaemic after a median of 20.5 days when no insulin was given post-transplantation. Four out of 5 animals became hyperglycaemic after a median of 23 days when supportive insulin therapy was administered after the transplantation. The results indicate that recurrent diabetes is not inevitable following syngeneic fetal pancreas transplantation to spontaneously diabetic BB rats. Recurrent diabetes was only occasionally associated with mononuclear cell infiltration. Transplanted tissue was well-preserved and vascularized; mega-islets were a constant finding. PMID:8401812

  5. Rat sequences of the Kirsten and Harvey murine sarcoma virus genomes: nature, origin, and expression in rat tumor RNA.

    PubMed Central

    Anderson, G R; Robbins, K C

    1976-01-01

    Two murine sarcoma viruses, the Kirsten and the Harvey, were isolated by passage of mouse type C leukemia viruses through rats. These sarcoma viruses have genomes containing portions of their parental type C mouse leukemia virus genomes, in stable association with specific rat cellular sequences that we find to be quite likely not those of a rat type C leukemia virus. To determine if these murine sarcoma viruses provide a model relevant to the events occurring in spontaneous tumors, we have hybridized DNA and RNA prepared from rat tumors and normal rat tissues to [3H]DNA prepared from the Kirsten murine sarcoma virus. We have also hybridized these rat tissue nucleic acids to [3H]DNA prepared from a respresentative endogenous rat type C leukemia virus, the WFU (Wistar-Furth). Sarcoma-viral rat cellular sequences and endogenous rat leukemia viral sequences were detected in the DNA of both tumor and normal tissues, with no evidence of either gene amplification or additional sequences being present in tumor DNA. Sarcoma-viral rat cellular sequences and endogenous rat leukemia viral sequences were detected at elevated concentrations in the RNA of many rat tumors and in specific groups of normal tissues. PMID:176419

  6. Small intestine biopotentials in rats after hypokinesia

    NASA Astrophysics Data System (ADS)

    Groza, P.; Stanciu, C.

    To study the effect of hypokinesia on rats small intestine (jejunum and ileum) biopotentials it was first necessary to characterize it. Biopotentials were recorded by intracellular placed microelectrodes from oral and caudal segments of the small intestine. The character of rats small intestine biopotentials differs from that of other species (man, cat, rabbit, dog, e.a.), the slow waves (SW) being smaller and the frequency of basal electrical rhythm higher (31.23 c/min orally and 24.50 caudally). Spike potentials are inscribed on the descending slope of SW but frequently delayed in each successive wave with a regular interval. Hypokinesia obtained by keeping rats in small cages for two weeks create only little changes in intestine biopotentials. The only clear difference was the increase of the slow waves amplitude. The other parameters were not specifically changed.

  7. Placentophagia in Weanling Female Laboratory Rats

    PubMed Central

    Harding, Kaitlyn M.; Lonstein, Joseph S.

    2014-01-01

    Placentophagia is common in parturient mammals and offers physiological and behavioral advantages for mothers. In natural environments, weanlings are often present during the birth of younger siblings, but it is unknown if weanling rats are placentophagic or prefer placenta over other substances. To examine this, primiparous rats were remated during the postpartum estrus and weanling females remained in the nest during their mother’s next parturition. Continuous observation revealed that 58% of weanlings were placentophagic. To determine if this placentophagia occurs away from parturient mothers, weanling females still living in their natal nest were offered placenta, liver, or cake frosting in a novel chamber. They ingested more placenta and liver than frosting. Thus, many weanling female laboratory rats are placentophagic during birth of younger siblings but do not selectively prefer placenta when tested outside their natal nest. Consequences of placentophagia by weanlings are unknown, but it may promote their alloparenting or postpartum mothering. PMID:24604548

  8. Vitelline cyst in the rat ileum

    PubMed Central

    Oshikata, Takafumi; Kobayashi, Azusa; Kumabe, Shino; Kawasako, Kazufumi; Katoku, Koshirou; Mitsuishi, Mikio; Kanno, Takeshi; Hamamura, Masao

    2015-01-01

    Congenital vitelline duct anomalies other than Meckel’s diverticulum are rare in animals. A cyst of approximately 8 mm in diameter was observed on the antimesenteric surface of the ileal serosa in a 10-week-old female Crl:CD(SD) rat. Microscopically, the cyst closely resembled the ileum, but it did not communicate with the ileal lumen. We diagnosed this case as a vitelline cyst derived from the vitelline duct based on the location where it developed and its histological behavior. In rats, only Meckel’s diverticulum has been reported with a congenital anomaly of the vitelline duct, and no other spontaneous anomalies including a vitelline cyst have been reported. This case may be the first report concerning a vitelline cyst in the rat ileum. PMID:26538812

  9. Opportunity Leaves a Trail of 'Rat' Holes

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Opportunity's rock abrasion tool, known informally as the 'Rat,' has nibbled seven holes into the slope of 'Endurance Crater.' This image from the rover's navigation camera was released previously (PIA06716) without the Rat holes labeled so that viewers could try to find the holes themselves. Here, the holes have been identified. Starting from the uppermost pictured (closest to the crater rim) to the lowest, the Rat hole targets are: 'Tennessee,' 'Cobblehill,' 'Virginia,' 'London,' 'Grindstone,' 'Kettlestone,' and 'Drammensfjorden.' These holes were drilled on sols 138 (June 13, 2004), 143 (June 18), 145 (June 20), 148 (June 23), 151 (June 26), 153 (June 28) and 161 (July 7), respectively. Each hole is 4.5 centimeters (1.8 inches) in diameter.

  10. Body temperature regulation and thermoneutrality in rats.

    PubMed

    Poole, S; Stephenson, J D

    1977-04-01

    Various concepts of thermoneutrality were considered for a proposed study of the role of hypothalamic amines in temperature regulation of rats. The classic definition, the ambient temperature over which metabolic rate is minimum and constant, gave a range of approximately 28 to 32 degrees C. However, within this temperature range rats were inactive, the inactivity apparently representing a behavioural response to heat stress and itself responsible for the reduced metabolic rate; certain thermoregulatory effectors were also activated to increase heat loss. Therefore an alternative range, 18.0 +/- 1.9 (mean +/- S.D.) to 28.1 +/- 1.0 degrees C, was defined in which rats displayed normal activity, behavioural thermoregulations being absent. PMID:585477

  11. Metabolic neural mapping in neonatal rats

    SciTech Connect

    DiRocco, R.J.; Hall, W.G.

    1981-01-01

    Functional neural mapping by /sup 14/C-deoxyglucose autoradiography in adult rats has shown that increases in neural metabolic rate that are coupled to increased neurophysiological activity are more evident in axon terminals and dendrites than neuron cell bodies. Regions containing architectonically well-defined concentrations of terminals and dendrites (neuropil) have high metabolic rates when the neuropil is physiologically active. In neonatal rats, however, we find that regions containing well-defined groupings of neuron cell bodies have high metabolic rates in /sup 14/C-deoxyglucose autoradiograms. The striking difference between the morphological appearance of /sup 14/C-deoxyglucose autoradiograms obtained from neonatal and adult rats is probably related to developmental changes in morphometric features of differentiating neurons, as well as associated changes in type and locus of neural work performed.

  12. Weight control and restraint of laboratory rats

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Van Breda Kolff, K.

    1979-01-01

    The use of restrained and confined rats in some procedures used in combustion toxicology introduces the problems of obtaining rats of the appropriate size for the apparatus, and of identifying any artifacts resulting from the use of restraint alone. Feeding studies indicate that controlled feeding of fast-growing strains such as the Sprague-Dawley can hold rat size essentially constant for significant periods of time. The undesirable aspects are the need to cage the animals individually, with resultant psychological as well as metabolic effects. Restraint studies of slow-growing strains such as the Fischer 344 indicate that denying access to food and water for periods of several hours at a time interrupts normal gain only temporarily.

  13. Ozone dosimetry predictions for humans and rats

    SciTech Connect

    Overton, J.H.; Graham, R.C.; McCurdy, T.R.; Richmond, H.M.

    1990-11-01

    The report summarizes ozone (O3) dosimetry model predictions for rats and humans under several different scenarios based on the most recent empirical data and theoretical considerations in the field of O3 dosimetry. The report was prepared at the request of the Office of Air Quality Planning and Standards (OAQPS) as an input to be considered by scientists participating in a chronic lung injury risk assessment project for O3. As indicated in the report a number of judgments and assumptions had to be made to obtain the dosimetry predictions. In addition to presenting the simulation results, the O3 dosimetry model used to make the predictions is discussed and the choice or method of selecting important physiological parameters explained. This includes anatomical dimensions, choices of rat and human ventilatory parameters, and the method of estimating human and rat upper respiratory tract uptake. Finally, a comparison of simulation results to recent experimental dosimetry results is discussed.

  14. Toxicity of oleic acid anilide in rats.

    PubMed

    Khan, M F; Kaphalia, B S; Palafox, A; Jerrells, T R; Ansari, G A

    1991-11-01

    In the present investigation, we have studied the toxic potential of oleic acid anilide (OAA) and heated oleic acid anilide (HOAA) in relation to the toxic oil syndrome (TOS). Male Sprague-Dawley rats were given 250 mg/kg of OAA or HOAA in mineral oil by gavage, on alternate days for 2 weeks (total 7 doses). The control rats received an equal volume of mineral oil only. The animals were sacrificed at days 1, 7, and 28 following the last dose. Ratio of organ-to-body weight showed increases in spleen and kidney of HOAA and OAA treated rats, respectively, at day 1 while this ratio for liver in HOAA treated group showed a decrease at day 1. Among blood parameters, white blood cells increased in HOAA treated group at day 1 and in both OAA and HOAA groups at day 28. Mean corpuscular hemoglobin (MCH) and mean cell volume (MCV) also showed increases in the HOAA treated rats at days 7 and 28. Serum lactate dehydrogenase (LDH) decreased in both OAA and HOAA treated rats at day 1, while at day 7 the decrease was confined only to the HOAA group. Serum glutamic oxalacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) activities also decreased at most of the time points. Liver mitochondrial ATPase activity decreased in the HOAA group at day 7 and in the OAA group at day 28. Among serum immunoglobulins, IgA levels increased throughout the study but the changes were more pronounced in HOAA treated rats.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1759851

  15. Rats exhibit reference-dependent choice behavior.

    PubMed

    Bhatti, Mehwish; Jang, Hyeran; Kralik, Jerald D; Jeong, Jaeseung

    2014-07-01

    Human preferences depend on whether a chosen outcome appears to be a loss or a gain compared with what had been expected, i.e., in comparison to a reference point. Because reference dependence has such a strong influence on human decision-making, it is important to uncover its origins, which will in turn help delineate the underlying mechanisms. It remains unknown whether rats use reference points in decision-making, and yet, the study of rats could help address the question of whether reference dependence is evolutionarily conserved among mammals and could provide a nonhuman animal model to investigate the neural mechanisms underlying this important cognitive process. The aim of the current study was to determine whether rats show reference-dependent choice behavior. We developed a novel paradigm by modifying the "T" maze by installing "pockets" to the left and right of the "T" stem that held reward pellets so rats would potentially develop reference values for each option prior to choice. We found that the rats were indeed sensitive to the way alternatives were presented. That is, they exhibited reference-dependent choice behavior by avoiding the choice option framed as a loss (e.g., having four reward pellets in the pocket, but receiving only one), at least under conditions with certain outcomes and clear differences between the reference and outcome quantities. Despite the small number of rats in this study, this species-level capacity suggests that reference dependence in general and loss aversion in particular may be conserved traits that evolved at or before the emergence of mammals. PMID:24657593

  16. Aspartame and the rat brain monoaminergic system.

    PubMed

    Perego, C; De Simoni, M G; Fodritto, F; Raimondi, L; Diomede, L; Salmona, M; Algeri, S; Garattini, S

    1988-12-01

    A high dose of aspartame (APM) was administered to rats to study possible effects on brain monoaminergic systems. APM and its metabolite phenylalanine (Phe) were given orally at doses of 1000 and 500 mg/kg, respectively. Significant increases were seen in brain Phe and tyrosine (Tyr) levels. Two different approaches were used to study monoaminergic systems: whole tissue measurements by HPLC-ED and in vivo voltammetry in freely moving rats. Dopamine, serotonin and their metabolites were taken as indexes of neuronal activity. In spite of the high dose used, no modification was found in monoamines or their metabolites in striatum, hippocampus and nucleus accumbens. PMID:2464204

  17. Glucose transporter expression in rat mammary gland.

    PubMed Central

    Burnol, A F; Leturque, A; Loizeau, M; Postic, C; Girard, J

    1990-01-01

    The expression of different glucose transporter isoforms was measured during the development and differentiation of the rat mammary gland. Before conception, when the mammary gland is mainly composed of adipocytes, Glut 4 and Glut 1 mRNAs and proteins were present. During pregnancy, the expression of Glut 4 decreased progressively, whereas that of Glut 1 increased. In the lactating mammary gland only Glut 1 was present, and was expressed at a high level. The absence of Glut 4 suggests that glucose transport is not regulated by insulin in the lactating rat mammary gland. Images Fig. 1. Fig. 2. PMID:2396989

  18. Subchronic oral toxicity of zinc in rats

    SciTech Connect

    Llobet, J.M.; Domingo, J.L.; Colomina, M.T.; Mayayo, E.; Corbella, J.

    1988-07-01

    It is well known that zinc has important biological functions. Clinical manifestations in zinc-deficient animals include growth retardation, testicular atrophy, skin changes, and poor appetite. On the other hand, high levels of dietary zinc have been shown to induce copper deficiency in rats and to interfere with the metabolism of calcium and iron. Little is known on the oral toxicity of zinc in mammals. However, some toxic effects in human subjects, rodents, and sheep have been reported. In order to extend the information about the oral toxicity of zinc, a semichronic toxicity study of zinc acetate in rats has been carried out in this paper.

  19. The oncogenic action of ionizing radiation on rat skin

    SciTech Connect

    Burns, F.J.

    1991-01-01

    Progress has occurred in several areas corresponding to the specific aims of the proposal: (1) Progression and multiple events in radiation carcinogenesis of rat skin as a function of LET; (2) cell cycle kinetics of irradiated rat epidermis as determined by double labeling and double emulsion autoradiography; (3) oncogene activation detected by in situ hybridization in radiation-induced rat skin tumors; (4) amplification of the c-myc oncogene in radiation-induced rat skin tumors as a function of LET; and (5) transformation of rat skin keratinocytes by ionizing radiation in combination with c-Ki-ras and c-myc oncogenes. 111 refs., 13 figs., 12 tabs.

  20. SCFA transport in rat duodenum

    PubMed Central

    Kaji, Izumi; Iwanaga, Toshihiko; Watanabe, Masahiko; Guth, Paul H.; Engel, Eli; Akiba, Yasutada

    2014-01-01

    Bacterial or ingested food-derived short-chain fatty acids (SCFAs) are present in the duodenal lumen. Acetate, the most abundant SCFA in the foregut lumen, is absorbed immediately after ingestion, although the mechanism by which this absorption occurs is not fully understood. We investigated the distribution and function of candidate SCFA transporters in rat duodenum. The Na+-coupled monocarboxylate transporter-1 (SMCT1) was localized to the brush border, whereas the pH-dependent monocarboxylate transporter (MCT) 1 and MCT4 were localized to the duodenocyte basolateral membrane. In Ussing chambered duodenal mucosa, luminal acetate dose-dependently increased short-circuit current (Isc) in the presence of serosal bumetanide and indomethacin by a luminal Na+-dependent, ouabain-sensitive mechanism. The Isc response was inhibited dose-dependently by the SMCT1 nonsubstrate inhibitor ibuprofen, consistent with net electrogenic absorption of acetate via SMCT1. Other SCFAs and lactate also increased Isc. Furthermore, duodenal loop perfusion of acetate increased portal venous acetate concentration, inhibited by coperfusion of ibuprofen or a MCT inhibitor. Luminal acetate perfusion increased duodenal HCO3− secretion via capsaicin-sensitive afferent nerve activation and cyclooxygenase activity, consistent with absorption-mediated HCO3− secretion. These results suggest that absorption of luminal SCFA via SMCT1 and MCTs increases duodenal HCO3− secretion. In addition to SCFA sensing via free fatty acid receptors, the presence of rapid duodenal SCFA absorption may be important for the suppression of luminal bacterial colonization and implicated in the generation of functional dyspepsia due to bacterial overgrowth. PMID:25394661

  1. Purinoceptors in the rat heart.

    PubMed Central

    Fleetwood, G.; Gordon, J. L.

    1987-01-01

    The effects of an intracoronary bolus of adenosine triphosphate (ATP), alpha, beta-methylene ATP (APCPP), beta, gamma-methylene ATP (APPCP), adenosine diphosphate (ADP), adenosine monophosphate (AMP) and adenosine on coronary tone and ventricular myocardial contraction were investigated in the perfused rat heart. Adenine nucleotides, given by bolus injection were negatively inotropic in amounts greater than 3 X 10(-7) mol. The potency order was ATP greater than ADP greater than AMP. Adenosine (less than 1 X 10(-5)mol) had no effect on ventricular myocardial contraction. Adenine nucleotides and adenosine (1 X 10(-10)-1 X 10(-7) mol) reduced coronary tone. The potency order was ATP greater than ADP greater than AMP = adenosine. The ATP analogue APPCP was less active than ATP at reducing coronary tone, and APCPP had no vasodilator effect. This suggests the presence of a P2-purinoceptor, subclass P2Y, which mediates vasodilation. ATP and ADP increased the concentration of prostacyclin (measured as 6-keto prostaglandin F1 alpha) in the perfusate, but only after injection of greater than 3 X 10(-7) mol, suggesting that the vasodilator responses to ATP and ADP were not mediated by prostacyclin. AMP and adenosine had no effect, even at 1 X 10(-5) mol. At a dose of 3 X 10(-9) mol, approximately 40% of ATP and 70% of ADP was converted to AMP and adenosine whilst passing through the heart. The amounts of AMP and adenosine formed, however, were insufficient to account for the vasodilator effects of ATP and ADP.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3814919

  2. Metabolism of pyridalyl in rats.

    PubMed

    Nagahori, Hirohisa; Saito, Koichi; Tomigahara, Yoshitaka; Isobe, Naohiko; Kaneko, Hideo

    2009-12-01

    Metabolism of pyridalyl [2,6-dichloro-4-(3,3-dichloroallyloxy)phenyl 3-[5-(trifluoromethyl)-2-pyridyloxy]propyl ether] was examined in male and female Sprague-Dawley rats. After a single oral administration of [dichlorophenyl-(14)C]pyridalyl at 5 or 500 mg/kg, the (14)C concentration in blood reached maxima at 2 to 10 h and then decreased rapidly with a biological half-life of approximately 11 to 12 h. (14)C concentrations in liver, fat, adrenal gland, and spleen were relatively high at a low dose, reaching 2.3 to 2.7, 1.9 to 2.3, 1.1 to 1.9, and 1.4 ppm, respectively, in these tissues at 2 to 24 h after administration. Although (14)C elimination from fat and hair and skin was relatively slow compared with that from other tissues, the total residue on the 7th day was low, in the range of 1.3 to 2.3% of the dose. The (14)C distribution in tissues with a high dose, as examined by whole-body autoradiography, was similar to that observed for the low dose. Results revealed that more than 88% of the dosed radiocarbon was excreted within 1 day after administration, with cumulative (14)C excretion into urine and feces 7 days after administration of 1.7 to 2.6 and 98.7 to 101.7%, respectively. One urinary and fecal major metabolite (resulting from O-dealkylation) and two minor metabolites were identified by NMR and mass spectrometry. Residual (14)C in fat was extracted, and analysis by thin-layer chromatography showed it to be due to pyridalyl itself. No marked sex-related differences were observed in (14)C elimination, (14)C distribution, and metabolites. PMID:19773539

  3. Glycoconjugate in rat taste buds.

    PubMed

    Kano, K; Ube, M; Taniguchi, K

    2001-05-01

    The taste buds of the fungiform papillae, circumvallate papilla, foliate papillae, soft palate and epiglottis of the rat oral cavity were examined by lectin histochemistry to elucidate the relationships between expression of glycoconjugates and innervation. Seven out of 21 lectins showed moderate to intense staining in at least more than one taste bud. They were succinylated wheat germ agglutinin (s-WGA). Dolichos biflorus agglutinin (DBA), Bandeiraea simplicifolia lectin-I (BSL-I), Ricinus communis agglutinin-I (RCA-I), peanut agglutinin (PNA), Ulex europaeus agglutinin-I (UEA-I) and Phaseolus vulgaris agglutinin-L (PHA-L). UEA-I and BSL-I showed moderate to intense staining in all of the taste buds examined. They strongly stained the taste buds of the epiglottis, which are innervated by the cranial nerve X. UEA-I intensely stained the taste buds of the fungiform papillae and soft palate, both of which are innervated by the cranial nerve VII. The taste buds of circumvallate papilla and foliate papillae were innervated by the cranial nerve IX and strongly stained by BSL-I. Thus, UEA-I and BSL-I binding glycoconjugates, probably alpha-linked fucose and alpha-D-galactose, respectively, might be specific for taste buds. Although the expression of these glycoconjugates would be related to the innervation of the cranial nerve X, the differential expression of alpha-linked fucose and alpha-D-galactose might be related to the innervation of the cranial nerve VII and IX, respectively. PMID:11411494

  4. Cecal infusion of nutrients improves nutritional status of rats.

    PubMed

    Aghdassi, E; Raina, N; Allard, J P

    1995-11-01

    The role of colonic fermentation in providing energy was investigated in rats with small bowel transection (T) or 80% resection (SBR). Rats were randomized to receive for 12 d either saline (S) or the enteral solution (E) through a cecostomy to meet 30% of energy requirement; the rest (70%) was provided by parenteral nutrition. Although SBR-S rats lost weight significantly compared with d 1 of the study, SBR-E rats gained. Significantly greater carcass wet weight and fat were found in SBR-E and T-E rats compared with SBR-S and T-S rats. SBR-E and T-E rats had significantly greater colonic mucosal dry weight and protein compared with SBR-S and T-S rats. Cecal short-chain fatty acid (SCFA) contents were also significantly higher in SBR-E and T-E rats compared with SBR-S and T-S rats. There was no significant effect of surgery (T vs. SBR) on any of the variables studied. These results suggest that the products of fermentation of an enteral solution infused through a cecostomy contribute substantially to energy requirement, maintenance of body composition and nutritional status of rats. PMID:7472670

  5. Erythrocyte Flow in Choriocapillaris of Normal and Diabetic Rats

    PubMed Central

    Braun, Rod D.; Wienczewski, Christopher A.; Abbas, Asad

    2009-01-01

    The choriocapillaris is a unique capillary bed that provides nutrients to the retinal photoreceptors. It changes anatomically in diabetes, but the impact of these changes on blood flow is unknown. In this study hemodynamic parameters in individual choriocapillaris vessels were compared in normal and diabetic rats. Three groups were studied: normal buffer-injected control rats, streptozotocin (STZ)-injected mildly hyperglycemic (STZ-MH) rats, and STZ-injected diabetic (STZ-D) rats. 7-8 weeks after STZ injection, the rats were anesthetized, and epifluorescent, intravital microscopy was used to record the flow of fluorescent red blood cells (RBC) in the choriocapillaris. Diameter, RBC flux, and RBC velocity were measured in 153 capillary pathways in five control rats, 98 pathways in four STZ-MH rats, and 153 pathways in seven STZ-D rats. There was no difference in capillary diameter among the groups. RBC flux and velocity were lower in the STZ-injected rats compared to the controls (p≤0.023), which is similar to changes found in other capillary beds. RBC velocity and flux were significantly correlated in all three groups, but the correlations in the STZ-injected rats were much stronger than in the controls. This indicates a more heterogeneous distribution of RBCs at upstream arteriolar branchpoints in hyperglycemic rats, which could lead to a decrease in choriocapillaris hematocrit. These changes in the hyperglycemic choriocapillaris could contribute to impaired oxygen delivery to the photoreceptors in diabetic retina. PMID:19269298

  6. [Foci of the rat mite Ornithonyssus bacoti (Mesostigmata, Macronyssidae) and rat-mite dermatitis in Moscow].

    PubMed

    Lopatina, Iu V; Sokolova, T V; Niiazova, M V

    1992-01-01

    High density of the rat population in Moscow in 1990-1991 resulted in the appearance of Ornithonyssus bacoti foci and of cases of the rat-mite dermatitis in humans. A total of 36 foci of the disease were examined and eradicated. A method for the detection of such foci has been developed. Two types of foci are distinguished, communal and industrial, and their specific features as regards the rodent and mite populations and clinical features of dermatitis in humans are described. A system of measures for liquidation of foci of rat mites is suggested, including rat and mite eradication and treatment of the patients. Specific features of these measures for various types of foci and in case of a focus reappearance are enumerated. PMID:1299760

  7. Inhibition of Mitosis and Macromolecular Synthesis in Rat Embryo Cells by Kilham Rat Virus

    PubMed Central

    Tennant, Raymond W.

    1971-01-01

    The effects of Kilham rat virus multiplication were studied in cultured rat embryo cells to examine the mechanisms by which virus infection might be related to developmental defects in rats and hamsters. The virus was found to inhibit motosis and deoxyribonucleic acid (DNA) synthesis within 2 to 10 hr after infection. However, total ribonucleic acid synthesis was relatively unaffected until about 20 hr after infection, and total protein synthesis did not decline significantly until loss of viable cells was apparent in the cultures. No effect on chromosomes was detected. The effect of Kilham rat virus on DNA synthesis appears to be due to inhibition of macromolecular synthesis rather than to an inhibition of uptake of precursors into cells. The effect of the virus on mitosis may be an addition to the effect on DNA synthesis, since mitosis is inhibited even in cultures in which cells are able to divide at the time of infection and which have presumably completed DNA synthesis. PMID:5167023

  8. Hepatitis E virus genotype 3 in wild rats, United States.

    PubMed

    Lack, Justin B; Volk, Kylie; Van Den Bussche, Ronald A

    2012-08-01

    The role of rodents in the epidemiology of zoonotic hepatitis E virus (HEV) infection has been a subject of considerable debate. Seroprevalence studies suggest widespread HEV infection in commensal Rattus spp. rats, but experimental transmission has been largely unsuccessful and recovery of zoonotic genotype 3 HEV RNA from wild Rattus spp. rats has never been confirmed. We surveyed R. rattus and R. norvegicus rats from across the United States and several international populations by using a hemi-nested reverse transcription PCR approach. We isolated HEV RNA in liver tissues from 35 of 446 rats examined. All but 1 of these isolates was relegated to the zoonotic HEV genotype 3, and the remaining sequence represented the recently discovered rat genotype from the United States and Germany. HEV-positive rats were detected in urban and remote localities. Genetic analyses suggest all HEV genotype 3 isolates obtained from wild Rattus spp. rats were closely related. PMID:22840202

  9. Hepatitis E Virus Genotype 3 in Wild Rats, United States

    PubMed Central

    Volk, Kylie; Van Den Bussche, Ronald A.

    2012-01-01

    The role of rodents in the epidemiology of zoonotic hepatitis E virus (HEV) infection has been a subject of considerable debate. Seroprevalence studies suggest widespread HEV infection in commensal Rattus spp. rats, but experimental transmission has been largely unsuccessful and recovery of zoonotic genotype 3 HEV RNA from wild Rattus spp. rats has never been confirmed. We surveyed R. rattus and R. norvegicus rats from across the United States and several international populations by using a hemi-nested reverse transcription PCR approach. We isolated HEV RNA in liver tissues from 35 of 446 rats examined. All but 1 of these isolates was relegated to the zoonotic HEV genotype 3, and the remaining sequence represented the recently discovered rat genotype from the United States and Germany. HEV-positive rats were detected in urban and remote localities. Genetic analyses suggest all HEV genotype 3 isolates obtained from wild Rattus spp. rats were closely related. PMID:22840202

  10. Core temperature of tailless rats exposed to centrifugation

    NASA Technical Reports Server (NTRS)

    Monson, C. B.; Oyama, J.

    1984-01-01

    The role of the tail in the altered thermoregulation of rats during acute exposure to hypergravity was investigated, using groups of rats of two ages: 55 days (young) and 138 days (old). Rectal and foot temperature changes were measured in intact and tailless rats subjected to 1 h centrifugation of 2.8 G, with preceding (1 h) and following (1-3 h) 1 G periods. At 22 C, the loss of body heat from the tail per se does not measurably contribute to the hypothermia induced by hypergravity. However, the heat loss from the feet was greater in the tailless rats than in the intact rats from the young group of animals, although there was no significant difference between the tailless and intact rats in the old animal group. It is concluded that the inhibition of heat production is a significant factor in the hypothermia of centrifuged tailless rats, as it has been previously shown to be in the intact animals.

  11. Witnessing traumatic events causes severe behavioral impairments in rats.

    PubMed

    Patki, Gaurav; Solanki, Naimesh; Salim, Samina

    2014-12-01

    Witnessing a traumatic event but not directly experiencing it can be psychologically quite damaging. In North America alone, ∼30% of individuals who witness a traumatic event develop post-traumatic stress disorder (PTSD). While effects of direct trauma are evident, consequences of indirect or secondary trauma are often ignored. Also unclear is the role of social support in the consequences of these experiences. The social defeat paradigm, which involves aggressive encounters by a large Long-Evans male rat (resident) towards a smaller Sprague-Dawley male rat (intruder), is considered a rodent model of PTSD. We have modified this model to create a trauma witness model (TWM) and have used our TWM model to also evaluate social support effects. Basically, when an intruder rat is placed into the home cage of a resident rat, it encounters an agonistic behavior resulting in intruder subordination. The socially defeated intruder is designated the SD rat. A second rat, the cage mate of the SD, is positioned to witness the event and is the trauma witnessing (TW) rat. Experiments were performed in two different experimental conditions. In one, the SD and TW rats were cagemates and acclimatized together. Then, one SD rat was subjected to three sessions of social defeat for 7 d. TW rat witnessed these events. After each social defeat exposure, the TW and SD rats were housed together. In the second, the TW and SD rats were housed separately starting after the first defeat. At the end of each protocol, depression-anxiety-like behavior and memory tests were conducted on the SD and TW rats, blood withdrawn and specific organs collected. Witnessing traumatic events led to depression- and anxiety-like behavior and produced memory deficits in TW rats associated with elevated corticosterone levels. PMID:24887568

  12. Witnessing traumatic events causes severe behavioral impairments in rats

    PubMed Central

    Patki, Gaurav; Solanki, Naimesh; Salim, Samina

    2015-01-01

    Witnessing a traumatic event but not directly experiencing it can be psychologically quite damaging. In North America alone, ~30% of individuals who witness a traumatic event develop post-traumatic stress disorder (PTSD). While effects of direct trauma are evident, consequences of indirect or secondary trauma are often ignored. Also unclear is the role of social support in the consequences of these experiences. The social defeat paradigm, which involves aggressive encounters by a large Long–Evans male rat (resident) towards a smaller Sprague–Dawley male rat (intruder), is considered a rodent model of PTSD. We have modified this model to create a trauma witness model (TWM) and have used our TWM model to also evaluate social support effects. Basically, when an intruder rat is placed into the home cage of a resident rat, it encounters an agonistic behavior resulting in intruder subordination. The socially defeated intruder is designated the SD rat. A second rat, the cage mate of the SD, is positioned to witness the event and is the trauma witnessing (TW) rat. Experiments were performed in two different experimental conditions. In one, the SD and TW rats were cagemates and acclimatized together. Then, one SD rat was subjected to three sessions of social defeat for 7 d. TW rat witnessed these events. After each social defeat exposure, the TW and SD rats were housed together. In the second, the TW and SD rats were housed separately starting after the first defeat. At the end of each protocol, depression-anxiety-like behavior and memory tests were conducted on the SD and TW rats, blood withdrawn and specific organs collected. Witnessing traumatic events led to depression- and anxiety-like behavior and produced memory deficits in TW rats associated with elevated corticosterone levels. PMID:24887568

  13. Palmitoylated PrRP analog decreases body weight in DIO rats but not in ZDF rats.

    PubMed

    Holubová, Martina; Zemenová, Jana; Mikulášková, Barbora; Panajotova, Vladimíra; Stöhr, Jiří; Haluzík, Martin; Kuneš, Jaroslav; Železná, Blanka; Maletínská, Lenka

    2016-05-01

    Anorexigenic neuropeptides produced and acting in the brain have the potential to decrease food intake and ameliorate obesity, but are ineffective after peripheral application, owing to a limited ability to cross the blood-brain barrier. We have designed lipidized analogs of prolactin-releasing peptide (PrRP), which is involved in energy balance regulation as demonstrated by obesity phenotypes of both Prrp-knockout and Prrp receptor-knockout mice. The aim of this study was to characterize the subchronic effect of a palmitoylated PrRP analog in two rat models of obesity and diabetes: diet-induced obese Sprague-Dawley rats and leptin receptor-deficient Zucker diabetic (ZDF) rats. In the rats with diet-induced obesity (DIO), a two-week intraperitoneal treatment with palmitoylated PrRP lowered food intake by 24% and body weight by 8%. This treatment also improved glucose tolerance and tended to decrease leptin levels and adipose tissue masses in a dose-dependent manner. In contrast, in ZDF rats, the same treatment with palmitoylated PrRP lowered food intake but did not significantly affect body weight or glucose tolerance, probably in consequence of severe leptin resistance due to a nonfunctional leptin receptor. Our data indicate a good efficacy of lipidized PrRP in DIO rats. Thus, the strong anorexigenic, body weight-reducing, and glucose tolerance-improving effects make palmitoylated PrRP an attractive candidate for anti-obesity treatment. PMID:26906745

  14. Piperlonguminine is neuroprotective in experimental rat stroke.

    PubMed

    Yang, Tiansong; Sun, Shixiao; Wang, Tiegang; Tong, Xin; Bi, Junhui; Wang, Yulin; Sun, Zhongren

    2014-12-01

    Inflammatory damage plays an important role in cerebral ischemic pathogenesis and may represent a target for treatment. Piperlonguminine (PE) has been proved to have anti-inflammatory actions. In this study, we investigated the effects of PE on cultured neuronal cell line, SH-SY5Y in vitro and experimental rat ischemic stroke in vivo. For oxygen-glucose deprivation (OGD) and tumor necrosis factor-α (TNF-α) stimulated SH-SY5Y cell line in vitro, SH-SY5Y cells were incubated with PE. In vivo, rats were subjected to middle cerebral artery occlusion (MACO) for 1h, followed by reperfusion for 23 h. The results of this study showed that treatment of SH-SY5Y cells with PE reduced the OGD-induced cytotoxicity and apoptosis and blocked TNF-α-induced activation of NF-κB and MAPK. Intraperitoneal injection of PE (2.4 mg/kg) produced a significant neuroprotective potential in rats with cerebral ischemia. PE attenuated neurological deficit scores, brain infarct volume and brain water content in rats, and inhibited activation of NF-κB and MAPK. These data show that PE protects the brain against ischemic cerebral injury via alleviating blood-brain barrier (BBB) breakdown, which may be mediated via inhibiting NF-κB and MAPK signaling pathways. PMID:25257731

  15. MECHANISMS OF CADMIUM ABSORPTION IN RATS

    EPA Science Inventory

    This study was undertaken in order to help clarify the factors which determine the fractional absorption of an oral load of cadmium (Cd) from the intestine of the rat. The experiments utilized intact segments of intestine, perfused or incubated in situ with their blood supply int...

  16. THE METABOLISM OF NALED INHALED BY RATS

    EPA Science Inventory

    Naled (Dibrom) was prepared with a (14)carbon label in the 1-ethyl position. The labeled compound was administered in appropriate formulation vehicles to female rats by the inhalation, oral or intraperitoneal routes. Treated animals were either placed in metabolism cages and thei...

  17. Okara ameliorates glucose tolerance in GK rats

    PubMed Central

    Hosokawa, Masaya; Katsukawa, Michiko; Tanaka, Hiroshi; Fukuda, Hitomi; Okuno, Sonomi; Tsuda, Kinsuke; Iritani, Nobuko

    2016-01-01

    Okara, a food by-product from the production of tofu and soy milk, is rich in three beneficial components: insoluble dietary fiber, β-conglycinin, and isoflavones. Although isoflavones and β-conglycinin have recently been shown to improve glucose tolerance, the effects of okara have not yet been elucidated. Therefore, we herein investigated the effects of okara on glucose tolerance in Goto-Kakizaki (GK) rats, a representative animal model of Japanese type 2 diabetes. Male GK rats were fed a 10% lard diet with or without 5% dry okara powder for 2 weeks and an oral glucose tolerance test was performed. Rats were then fed each diet for another week and sacrificed. The expression of genes that are the master regulators of glucose metabolism in adipose tissue was subsequently examined. No significant differences were observed in body weight gain or food intake between the two groups of GK rats. In the oral glucose tolerance test, increases in plasma glucose levels were suppressed by the okara diet. The mRNA expression levels of PPARγ, adiponectin, and GLUT4, which up-regulate the effects of insulin, were increased in epididymal adipose tissue by the okara diet. These results suggest that okara provides a useful means for treating type 2 diabetes. PMID:27257347

  18. EVALUATION OF RENAL FUNCTION IN NEONATAL RATS

    EPA Science Inventory

    The ontogenetic profile of several parameters of neonatal renal development in the rat is presented. Nephrogenesis was observed to continue at a rapid pace between birth and 8 days of age and to be virtually complete by 11 days of age. The activity of alkaline phosphatase, a brus...

  19. Pack rats (Neotoma spp.): Keystone ecological engineers?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential role of two species of pack rats (Neotoma albigula and Neotoma micropus) as keystone ecological engineers was examined by estimating the species diversity of invertebrates living in the nest middens, and nitrogen mineralization rates in soils associated with the middens. Although pack-...

  20. Voluntary Oral Administration of Losartan in Rats.

    PubMed

    Diogo, Lucília N; Faustino, Inês V; Afonso, Ricardo A; Pereira, Sofia A; Monteiro, Emília C; Santos, Ana I

    2015-09-01

    Gavage is a widely performed technique for daily dosing in laboratory rodents. Although effective, gavage comprises a sequence of potentially stressful procedures for laboratory animals that may introduce bias into experimental results, especially when the drugs to be tested interfere with stress-dependent parameters. We aimed to test vehicles suitable for drug delivery by voluntary ingestion in rats. Specifically, Male Wistar rats (age, 2 to 3 mo) were used to test nut paste (NUT), peanut butter (PB), and sugar paste (SUG) as vehicles for long-term voluntary oral administration of losartan, an angiotensin II receptor blocker. Vehicles were administered for 28 d without drug to assess effects on the glucose level and serum lipid profile. Losartan was mixed with vehicles and either offered to the rats or administered by gavage (14 d) for subsequent quantification of losartan plasma levels by HPLC. After a 2-d acclimation period, all rats voluntarily ate the vehicles, either alone or mixed with losartan. NUT administration reduced blood glucose levels. The SUG group had higher concentrations of losartan than did the gavage group, without changes in lipid and glucose profiles. Our results showed that NUT, PB, and SUG all are viable for daily single-dose voluntary ingestion of losartan and that SUG was the best alternative overall. Drug bioavailability was not reduced after voluntary ingestion, suggesting that this method is highly effective for chronic oral administration of losartan to laboratory rodents. PMID:26424254

  1. Interaction between succinylcholine and cimetidine in rats.

    PubMed

    Mishra, Y; Ramzan, I

    1992-04-01

    The hypothesis that histamine H2 receptor blockade adversely affects neuromuscular function was tested, in vivo, in rats anaesthetised with urethane during mechanical pulmonary ventilation. Succinylcholine was administered as a bolus and constant-rate infusion to maintain 49.2% (+/- 1.5 SEM) twitch suppression in 19 rats. Cimetidine iv, 3.2, 7.5, 10, 17.8, 23.7, 31.6, or 56.2 mg.kg-1 was then administered in groups of two to three rats. Cimetidine produced an immediate potentiation of twitch suppression followed by a transient reversal and then a continued potentiation. Peak potentiation occurred within 19.0 (+/- 2.7) sec and was maintained in 11 rats at steady-state. Reversal was evident 4.1 (+/- 0.4) min after cimetidine administration. There was a good relationship between peak potentiation and serum cimetidine concentration with 50% potentiation occurring at 46.5 (+/- 4.6) micrograms.ml-1. Potentiation at steady-state was not correlated to serum cimetidine concentration but there was a weak relationship between reversal and serum cimetidine concentration. These results support reports from patients of an interaction between cimetidine and succinylcholine. PMID:1314141

  2. Prenatal Caffeine Exposure Impairs Pregnancy in Rats

    PubMed Central

    Yadegari, Maryam; Khazaei, Mozafar; Anvari, Morteza; Eskandari, Mohadeseh

    2016-01-01

    Background In recent years, concerns have been raised about human reproductive disorders. Caffeine consumption is increasing by the world’s population and there is a relationship between caffeine intake and adverse reproductive outcomes. The aim of this study was to evaluate the effects of caffeine on implantation sites, number of live births, birth weight, crown-rump length (CRL) and abnormality in pregnant rats. Materials and Methods In this experimental study, 40 female albino rats (170-190 g) were randomly divided into two experimental and two control groups (n=10/each group). In both experimental groups, animals received caffeine intraperitoneally (IP: 150 mg/kg/day) on days 1-5 of pregnancy. In experimental group 1, treated animals were euthanized on day 7of pregnancy and the number of implantation sites was counted. In experimental group 2, treated animals maintained pregnant and after delivery, the number of live births, birth weight, CRL and abnormality of neonates were investigated. In control group, animals received IP injections of distilled water. Data were analyzed by independent t test. Results Results showed that administration of caffeine significantly decreased the number of implantation sites, number of live births and CRL as compared with control group (P<0.05). There were no significant differences regarding birth weight and abnormality of neonate rats between experimental and control groups. Conclusion These results suggest that caffeine caused anti-fertility effect and significantly decreased CRL in neonate rats. PMID:26985345

  3. Voluntary Oral Administration of Losartan in Rats

    PubMed Central

    Diogo, Lucília N; Faustino, Inês V; Afonso, Ricardo A; Pereira, Sofia A; Monteiro, Emília C; Santos, Ana I

    2015-01-01

    Gavage is a widely performed technique for daily dosing in laboratory rodents. Although effective, gavage comprises a sequence of potentially stressful procedures for laboratory animals that may introduce bias into experimental results, especially when the drugs to be tested interfere with stress-dependent parameters. We aimed to test vehicles suitable for drug delivery by voluntary ingestion in rats. Specifically, Male Wistar rats (age, 2 to 3 mo) were used to test nut paste (NUT), peanut butter (PB), and sugar paste (SUG) as vehicles for long-term voluntary oral administration of losartan, an angiotensin II receptor blocker. Vehicles were administered for 28 d without drug to assess effects on the glucose level and serum lipid profile. Losartan was mixed with vehicles and either offered to the rats or administered by gavage (14 d) for subsequent quantification of losartan plasma levels by HPLC. After a 2-d acclimation period, all rats voluntarily ate the vehicles, either alone or mixed with losartan. NUT administration reduced blood glucose levels. The SUG group had higher concentrations of losartan than did the gavage group, without changes in lipid and glucose profiles. Our results showed that NUT, PB, and SUG all are viable for daily single-dose voluntary ingestion of losartan and that SUG was the best alternative overall. Drug bioavailability was not reduced after voluntary ingestion, suggesting that this method is highly effective for chronic oral administration of losartan to laboratory rodents. PMID:26424254

  4. Okara ameliorates glucose tolerance in GK rats.

    PubMed

    Hosokawa, Masaya; Katsukawa, Michiko; Tanaka, Hiroshi; Fukuda, Hitomi; Okuno, Sonomi; Tsuda, Kinsuke; Iritani, Nobuko

    2016-05-01

    Okara, a food by-product from the production of tofu and soy milk, is rich in three beneficial components: insoluble dietary fiber, β-conglycinin, and isoflavones. Although isoflavones and β-conglycinin have recently been shown to improve glucose tolerance, the effects of okara have not yet been elucidated. Therefore, we herein investigated the effects of okara on glucose tolerance in Goto-Kakizaki (GK) rats, a representative animal model of Japanese type 2 diabetes. Male GK rats were fed a 10% lard diet with or without 5% dry okara powder for 2 weeks and an oral glucose tolerance test was performed. Rats were then fed each diet for another week and sacrificed. The expression of genes that are the master regulators of glucose metabolism in adipose tissue was subsequently examined. No significant differences were observed in body weight gain or food intake between the two groups of GK rats. In the oral glucose tolerance test, increases in plasma glucose levels were suppressed by the okara diet. The mRNA expression levels of PPARγ, adiponectin, and GLUT4, which up-regulate the effects of insulin, were increased in epididymal adipose tissue by the okara diet. These results suggest that okara provides a useful means for treating type 2 diabetes. PMID:27257347

  5. Central action of phenylethylamine in rats.

    PubMed

    Jagiełło-Wójtowicz, E

    1981-01-01

    Phenylethylamine (PEA), 10, 50 and 100 microgram/rat ivc depressed the spontaneous and explorative motor activities, did not affect the body temperature and potentiated the action of hypnotics. The PEA-induced depression of motor activity was antagonized by spiperone, phenoxybenzamine, propranolol and, slightly, by alpha-MT. In rats with total chemical destruction of catecholamine neurons and in rats with selective lesion of dopamine neurons, PEA increased motor activity. Similar effect was observed after administration of reserpine, reserpine together with 6-hydroxydopamine and yohimbine. PEA potentiated the amphetamine and apomorphine stereotypy but inhibited amphetamine hypermotility: in the latter experiment slight periodical stereotyped head movements were observed. PEA did not affect haloperidol and fluphenazine induced catalepsy. It did not change the immobility period in the behavioral despair test. In doses of 0 . 1, 1 and 10 mg/kg iv it potentiated flexor reflex of the hind paw of the spinal rat. Phentolamine (10 mg/kg iv) and propranolol (5 mg/kg iv) slightly potentiated the stimulatory effect of PEA. In doses of 50 and 100 microgram ivc PEA did not affect the level and utilization of noradrenaline, and did not change the level of dopamine but depressed its utilization in the cerebral cortex, striatum and hippocampus. PMID:7196039

  6. TASTE DISCRIMINATION LEARNING IN PREWEANLING RATS

    EPA Science Inventory

    Seventeen-day-old rat pups received intraoral infusions of two novel flavors, coffee (.625% w/v Sanka, decaffeinated) and saccharin (.5% w/v), of which one (CS+) was paired with a .75X body weight, i.p. injection of 0.4 M LiCl, and the other (CS-) was presented alone. n the follo...

  7. DEVELOPMENTAL NEUROTOXICITY OF INHALED METHANOL IN RATS

    EPA Science Inventory

    Dr. Weiss and his colleagues conducted a controlled series of experiments in which they exposed pregnant rats and their newborn offspring to 4,500 parts per million (ppm) methanol by inhalation, and then submitted them to tests of behavioral function.

    Exposure to 4,500...

  8. On the absorption of alendronate in rats.

    PubMed

    Lin, J H; Chen, I W; deLuna, F A

    1994-12-01

    Alendronate is an antiosteolytic agent under investigation for the treatment of a number of bone disorders. Since the compound is a zwitterion with five pKa values and is completely ionized in the intestine at the physiological pH, absorption is poor; less than 1% of an oral dose is available systemically in rats. In the present studies, absorption was found to be predominantly in the upper part of the small intestine. Administration of buffered solutions of alendronate (pH 2-11) did not improve absorption. Whereas food markedly impaired the absorption of alendronate, EDTA enhanced absorption in a dose-dependent manner. Pretreatment of rats with ulcerogenic agents, mepirizole, acetylsalicylic acid, or indomethacin, resulted in a 3-7-fold increase in the oral absorption of alendronate. The absorption of phenol red, added as an indicator of intestinal tissue damage, was also increased in rats with experimental peptic ulcers. The enhanced absorption of alendronate observed in rats with experimental peptic ulcers was attributed to the alteration of the integrity of the intestinal membrane. PMID:7891304

  9. Baroreflex Function in Rats after Simulated Microgravity

    NASA Technical Reports Server (NTRS)

    Hasser, Eileen M.

    1997-01-01

    Prolonged exposure of humans to decreased gravitational forces during spaceflight results in a number of adverse cardiovascular consequences, often referred to as cardiovascular deconditioning. Prominent among these negative cardiovascular effects are orthostatic intolerance and decreased exercise capacity. Rat hindlimb unweighting is an animal model which simulates weightlessness, and results in similar cardiovascular consequences. Cardiovascular reflexes, including arterial and cardiopulmonary baroreflexes, are required for normal adjustment to both orthostatic challenges and exercise. Therefore, the orthostatic intolerance and decreased exercise capacity associated with exposure to microgravity may be due to cardiovascular reflex dysfunction. The proposed studies will test the general hypothesis that hindlimb unweighting in rats results in impaired autonomic reflex control of the sympathetic nervous system. Specifically, we hypothesize that the ability to reflexly increase sympathetic nerve activity in response to decreases in arterial pressure or blood volume will be blunted due to hindlimb unweighting. There are 3 specific aims: (1) To evaluate arterial and cardiopulmonary baroreflex control of renal and lumbar sympathetic nerve activity in conscious rats subjected to 14 days of hindlimb unweighting; (2) To examine the interaction between arterial and cardiopulmonary baroreflex control of sympathetic nerve activity in conscious hindlimb unweighted rats; (3) to evaluate changes in afferent and/or central nervous system mechanisms in baroreflex regulation of the sympathetic nervous system. These experiments will provide information related to potential mechanisms for orthostatic and exercise intolerance due to microgravity.

  10. Consensus Modeling of Oral Rat Acute Toxicity

    EPA Science Inventory

    An acute toxicity dataset (oral rat LD50) with about 7400 compounds was compiled from the ChemIDplus database. This dataset was divided into a modeling set and a prediction set. The compounds in the prediction set were selected so that they were present in the modeling set used...

  11. AUTOMATIVE QUANTIFICATION OF RAT DUODENAL RHYTHMIC CONTRACTION

    EPA Science Inventory

    The pacemaker activity of longitudinal muscle, as reflected by in vitro rhythmic contractions of the adult male rat's duodenum, has been examined in terms of intercontraction intervals that were collected using a microprocessor-based system. For each duodenal segment studied, 512...

  12. Neurons from rat brain coupled to transistors

    NASA Astrophysics Data System (ADS)

    Vassanelli, S.; Fromherz, P.

    Field-effect transistors form spontaneously capacitive junctions with cultured nerve cells from rat brains. The transfer of ac signals from neurons to silicon is studied and used to parametrize an equivalent circuit. The coupling is distinctly weaker than in junctions assembled with leech nerve cells. The implications with respect to the recording and stimulation of neuronal activity by silicon devices are considered.

  13. TRIMETHYLTIN REDUCES RECURRENT INHIBITION IN RATS

    EPA Science Inventory

    Rats with electrodes chronically implanted in the perforant path for electrical stimulation, and dentate gyrus for recording were treated with a single oral administration of either saline, 5 mg/kg trimethyltin (TMT) or 6 mg/kg TMT. Recurrent inhibition was assessed by paired pul...

  14. Surgical techniques of orthotopic rat liver transplantation.

    PubMed

    Spiegel, H U; Palmes, D

    1998-01-01

    Liver transplantation in rats is frequently used as a transplantation model. Although liver transplantation in larger laboratory animals such as dogs and pigs is technically easier, the rat has become the most important subject for experimental liver transplantation because of the availability of genetically defined animals. Numerous surgical techniques have been developed that permit the investigator to carry out studies with high clinical relevance. In this article the principal models of orthotopic rat liver transplantation and their technical modifications of vessel anastomoses, rearterialization, and bile duct reconstruction techniques are reviewed. More than 20 transplantation models are described in detail and demonstrated with clear illustrations. Finally, the advantages and uses of all the surgical procedures (e.g., suture and cuff anastomoses, bile duct anastomoses, and rearterialization techniques), specific problems, and survival criteria are discussed and the experiences of investigators who applied these techniques are analyzed. In conclusion, an overview and critical evaluation of all surgical techniques of orthotopic rat liver transplantation are given, together with instructions for learning these techniques. PMID:9700616

  15. Copper deficiency decreases plasma homocysteine in rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to determine the effects of copper deficiency on key aspects of homocysteine metabolism that involve methionine recycling and transsulfuration. Male weanling Sprague-Dawley rats were fed AIN-93-G-based diets containing <1 or approximately 6 mg Cu/kg. After 6 wk (experim...

  16. The rat choledochojejunostomy model for microsurgical training

    PubMed Central

    Lee, Jun Suh

    2016-01-01

    Purpose The feasibility of a rat choledochojejunostomy (CJ) training model was investigated, as an introductory model to microsurgery for general surgeons. Methods Roux-en-Y CJ was performed on 20 rats. Interrupted 10-0 prolene sutures were used to perform CJ. The animals were observed for 7 days and sacrificed and examined. Results The rats were divided into 2 groups of 10 based on surgical order. The CJ time showed a significant decrease from 36.2 ± 5.6 minutes in group 1 to 29.4 ± 5.7 minutes in group 2 (P = 0.015). The bile leakage rate was 40% in group 1 and 10% in group 2. The survival time was 5.4 ± 2.2 days in group 1 and 7 days in group 2 (P = 0.049). Conclusion The rat CJ training model is a feasible introductory model for general surgeons with no previous experience in microsurgery. PMID:27186568

  17. Spatial memory in spontaneously hypertensive rats (SHR).

    PubMed

    Sontag, Thomas-A; Fuermaier, Anselm B M; Hauser, Joachim; Kaunzinger, Ivo; Tucha, Oliver; Lange, Klaus W

    2013-01-01

    The spontaneously hypertensive rat (SHR) is an established animal model of ADHD. It has been suggested that ADHD symptoms arise from deficits in executive functions such as working memory, attentional control and decision making. Both ADHD patients and SHRs show deficits in spatial working memory. However, the data on spatial working memory deficits in SHRs are not consistent. It has been suggested that the reported cognitive deficits of SHRs may be related to the SHRs' locomotor activity. We have used a holeboard (COGITAT) to study both cognition and activity in order to evaluate the influence of the activity on the cognitive performance of SHRs. In comparison to Wistar-Kyoto (WKY) rats, SHRs did not have any impairment in spatial working memory and reference memory. When the rats' locomotor activity was taken into account, the SHRs' working memory and reference memory were significantly better than in WKY rats. The locomotor activity appears to be a confounding factor in spatial memory tasks and should therefore be controlled for in future studies. In the SHR model of ADHD, we were unable to demonstrate an impairment of working memory which has been reported in patients with ADHD. PMID:24009775

  18. NAT THE RAT - PUPIL'S BOOK. (TITLE SUPPLIED).

    ERIC Educational Resources Information Center

    ROJAS, PAULINE M.; AND OTHERS

    THE EXPERIMENTAL EDITION OF "NAT THE RAT" REPRESENTS LEVEL TWO OF THE "MIAMI LINGISTIC READERS" DESIGNED TO BE USED IN TEACHING BEGINNING READING TO PUPILS WHOSE PRESCHOOL LANGUAGE WAS OTHER THAN ENGLISH. THE FIVE MAJOR CHARACTERS IN THE STORY ARE INTRODUCED ON THE FIRST FIVE PAGES OF THE PUPILS' BOOK. ILLUSTRATIONS (BLACK AND WHITE) TO REINFORCE…

  19. METABOLISM AND DOSIMETRY OF VINCLOZOLIN IN RAT

    EPA Science Inventory

    Vinclozolin (V) is an agricultural fungicide. V administered to rats is hydrolyzed to 2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3-butenoic acid (M1) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2). V, M1and M2 are antiandrogenic by interacting with the androgen r...

  20. Microvascular effects of copper deficiency in rats

    SciTech Connect

    Schuschke, D.A.; Saari, J.T.; Ackermann, D.M.; Miller, F.N. )

    1989-02-15

    We have studied the microcirculatory responses in copper deficient rats using the rat cremaster muscle preparation. Male Sprague-Dawley rats were fed either a copper supplemented diet (CuS, 5 ppm) or a copper deficient diet (CuD, O ppm) for five weeks prior to experimentation. The rats (240-300g) were anesthetized with pentobarbital and the cremaster (with intact nerve and blood supply) were spread in a tissue bath filled with krebs solution. In vivo television microscopy was used to observe the microcirculation. Fluorescein isothiocyanate tagged to bovine serum albumin (FITC-BSA) was injected i.a. 30 min prior to the start of experimentation. In the CuS animals photoactivation of the intravascular FITC-BSA caused significant platelet aggregation and reduction in red blood cell column diameter (RBCCD) by 30 min and stasis of flow by 60 min. In CuD animals there was no reduction in RBCCD and only minor platelet aggregation after 60 min of photoactivation. Topical administration of compound 48/80 (1.0 and 10.0 {mu}g/ml) induced a significantly greater macromolecular leakage (increased interstitial fluorescence of FITC-BSA) in the CuD animals than in the control, CuS animals. These results suggest that copper deficiency results in marked alterations of the regulatory mechanisms governing thrombosis and inflammation.

  1. Cardiac Muscle Studies with Rat Ventricular Strips

    ERIC Educational Resources Information Center

    Whitten, Bert K.; Faleschini, Richard J.

    1977-01-01

    Details undergraduate physiology laboratory experiments that demonstrate mechanical properties of cardiac muscle, using strips from the ventricle of a rat heart. Includes procedures for obtaining length-tension curves, demonstrating the role of calcium in excitation-contraction coupling, and showing effects of several cardiovascular drugs…

  2. Avenanthramide bioavailability and tissue distribution in rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avenanthramides (AVA) are antioxidants found exclusively in oats. The aim of this study was to determine the time course of absorption of AVA into plasma, liver, and other tissues following their oral ingestion. Three fractions of AVA (AVN-A, AVN-B, and AVN-C) were fed to female Sprague-Dawley rat...

  3. Regional distribution of rat electroolfactogram.

    PubMed

    Ezeh, P I; Davis, L M; Scott, J W

    1995-06-01

    1. Electroolfactorgram (EOG) recordings were made from different regions of the rat olfactory epithelium to test for spatial distribution of odor responses. 2. The EOG recordings showed spatial distribution of the odor responses in the olfactory epithelium. While some odorants (amyl acetate, anisole, and ethyl butyrate) were more effective in evoking responses in the dorsal recess near the septum, other odorants (including limonene, cineole, cyclooctane, and hexane) were more effective in the lateral recesses among the turbinate bones. These differences were seen as statistically significant odorant-by-position interactions in analysis of variance. 3. Comparisons of recordings along the anteroposterior dimension of the epithelium produced smaller differences between the odor responses. These were not significant for 3-mm distances, but were statistically significant for 5- to 6-mm distances along the dorsomedial epithelium. 4. The latencies were significantly longer in the lateral recesses than in the medial region. This probably reflects a more tortuous air path along the turbinate bones to the lateral recesses. 5. The olfactory receptor cells were activated by antidromic stimulation via the nerve layer of the olfactory bulb. The population spikes evoked from the olfactory receptor cells could be suppressed by prior stimulation with odorants that evoked strong EOG responses. This collision of the antidromic action potentials with the odor-evoked action potentials indicates that the same population of receptor cells was activated in both cases. 6. The flow rate and duration of the artificial sniff were varied systematically in some experiments. The differential distribution of response sizes was present at all flow rates and sniff durations. Some odors (e.g., amyl acetate and anisole) produced increased responses in the epithelium of the lateral recesses when flow rates or sniff durations were high. We suggest that these changes may reflect the sorptive properties

  4. Helminth parasites in black rats (Rattus rattus) and brown rats (Rattus norvegicus) from different environments in the Netherlands

    PubMed Central

    Franssen, Frits; Swart, Arno; van Knapen, Frans; van der Giessen, Joke

    2016-01-01

    Background Rattus norvegicus (brown rat) and Rattus rattus (black rat) are known carriers of bacteria, viruses, and parasites of zoonotic and veterinary importance. Moreover, rats may play a role in the transmission of muscle larvae of the zoonotic nematode Trichinella spiralis to farm animals. We aimed to study the intestinal and intramuscular helminths in wild rats from three different environments to assess the relevance of rats as carrier of zoonotic parasites for public health. Materials and methods Wild brown rats (117 individuals) and black rats (44 individuals) were captured at farms, in suburban and in rural environments in the Netherlands. Intestinal helminths were isolated and identified morphologically. Artificial digestion was used to isolate muscle larvae. Results and discussion Morphological analysis of rat intestinal contents yielded six nematode species (Syphacia muris, Heterakis spumosa, Aonchotheca murissylvatici, Trichuris muris, Nippostrongylus brasiliensis, and Strongyloides sp.), three cestode species (Hymenolepis diminuta, H. nana and Hymenolepis (=Rodentolepis) fraterna), and four trematode species (Plagiorchis muris, Plagiorchis proximus, Echinostoma chloropodis, and Notocotylus imbricatus). Black rats at farms displayed the lowest intestinal helminth species variation (six species) and carried overall on average 0.93 species simultaneously. In comparison, brown rats at farms carried seven helminth species and 1.91 species simultaneously. Brown rats from suburban environments displayed the highest species variation (11 species) at 1.82 simultaneous helminth species. Absence of trematodes from rats at farms may suggest limited exchange of rats between farms and surrounding wet rural environments. We report four species of veterinary (Syphacia muris) or zoonotic relevance (Hymenolepis diminuta, Hymenolepis nana and Plagiorchis muris). We did not find Trichinella muscle larvae, consistent with long-term prevalence in Dutch wild rats. PMID

  5. Ontogeny of the rat hepatic adrenoceptors

    SciTech Connect

    McMillian, M.K.

    1985-01-01

    Hepatic alpha-1, alpha-2, and beta-2 adrenoceptors were characterized during development of the rat through Scatchard analysis of (/sup 3/H)-prazosin, (/sup 3/H)-rauwolscine and (/sup 125/I)-pindolol binding to washed particle membrane preparations. Major changes in adrenoceptor number occur shortly before birth and at weaning. The fetal rat liver is characterized by a large number of alpha-2 adrenoceptors which falls 10-20 fold at birth. The number of hepatic beta adrenoceptors decreases 30-50% during the third week after birth increases slightly at weaning, then decreases gradually in the adult. Hepatic alpha-1 adrenoceptor number increases 3-5 fold at weaning to become the predominant adrenoceptor in the adult rat liver. The basis for the fall in alpha-2 number at birth remains unclear. The fall in beta receptor number at the end of the second week post-natally appears dependent on increased insulin and corticosterone secretion as well as increased NE release form nerve terminals. The basis for the increase in beta number at weaning and the sex-dependent loss of beta function but not receptor number in the adult rat remains unknown. The dramatic increases in alpha-1 number and function at weaning are dependent on increased adrenocortical secretion, adrenalectomy prevents the normal. This effect of adrenocorticoids might be mediated through glycogen, as glycogen depletion during fasting decreases alpha-1 receptor number and function at weaning are dependent on increased adrenocortical secretion, adrenalectomy prevents the normal. This effect of adrenocorticoids might be mediated through glycogen, as glycogen depletion during fasting decreases alpha-1 receptor number and function. These findings suggest that hepatic adrenoceptor number adapts from the low carbohydrate diet of the suckling rat to the high carbohydrate diet of the adult at weaning.

  6. Revisiting the supratrigeminal nucleus in the rat.

    PubMed

    Fujio, T; Sato, F; Tachibana, Y; Kato, T; Tomita, A; Higashiyama, K; Ono, T; Maeda, Y; Yoshida, A

    2016-06-01

    The supratrigeminal nucleus (Vsup), originally proposed as a premotoneuron pool in the trigeminal reflex arc, is a key structure of jaw movement control. Surprisingly, however, the location of the rat Vsup has not precisely been defined. In light of our previous cat studies, we made two hypotheses regarding the rat Vsup: (1) the Vsup is cytoarchitectonically distinguishable from its surrounding structures; (2) the Vsup receives central axon terminals of the trigeminal mesencephalic nucleus (Vmes) neurons which are primary afferents innervating muscle spindles of jaw-closing muscles and periodontal ligaments around the teeth. To test the first hypothesis, we examined the cytoarchitecture of the rat Vsup. The Vsup was identified as an area medially adjacent to the dorsomedial part of trigeminal principal sensory nucleus (Vp), and extended from the level just rostral to the caudal two-thirds of the trigeminal motor nucleus (Vmo) to the level approximately 150μm caudal to the Vmo. Our rat Vsup was much smaller and its location was considerably different in comparison to the Vsup reported previously. To evaluate the second hypothesis, we tested the distribution patterns of Vmes primary afferent terminals in the cytoarchitectonically identified Vsup. After transganglionic tracer applications to the masseter, deep temporal, and medial pterygoid nerves, a large number of axon terminals were observed in all parts of Vsup (especially in its medial part). After applications to the inferior alveolar, infraorbital, and lingual nerves, a small number of axon terminals were labeled in the caudolateral Vsup. The Vsup could also be identified electrophysiologically. After electrical stimulation of the masseter nerve, evoked potentials with slow negative component were isolated only in the Vsup. The present findings suggest that the rat Vsup can be cytoarchitectonically and electrophysiologically identified, receives somatotopic termination of the trigeminal primary afferents, and

  7. Thallium kinetics in rat cardiac transplant rejection

    SciTech Connect

    Barak, J.H.; LaRaia, P.J.; Boucher, C.A.; Fallon, J.T.; Buckley, M.J.

    1988-04-01

    Cardiac transplant rejection is a very complex process involving both cellular and vascular injury. Recently, thallium imaging has been used to assess acute transplant rejection. It has been suggested that changes in thallium kinetics might be a sensitive indicator of transplant rejection. Accordingly, thallium kinetics were assessed in vivo in acute untreated rat heterotopic (cervical) transplant rejection. Male Lewis rats weighing 225-250 g received heterotopic heart transplants from syngeneic Lewis rats (group A; n = 13), or allogeneic Brown Norway rats (group B; n = 11). Rats were imaged serially on the 2nd and the 7th postoperative days. Serial cardiac thallium content was determined utilizing data collected every 150 sec for 2 hr. The data were fit to a monoexponential curve and the decay rate constant (/sec) derived. By day 7 all group B hearts had histological evidence of severe acute rejection, and demonstrated decreased global contraction. Group A hearts showed normal histology and contractility. However, thallium uptakes and washout of the two groups were the same. Peak thallium uptake of group B was +/- 3758 1166 counts compared with 3553 +/- 950 counts in the control group A (P = 0.6395); The 2-hr percentage of washout was 12.1 +/- 1.04 compared with 12.1 +/- 9.3 (P = 1.0000); and the decay constant was -0.00002065 +/- 0.00001799 compared with -0.00002202 +/- 0.00001508 (P = 0.8409). These data indicate that in vivo global thallium kinetics are preserved during mild-to-severe acute transplant rejection. These findings suggest that the complex cellular and extracellular processes of acute rejection limit the usefulness of thallium kinetics in the detection of acute transplant rejection.

  8. Laser welding of rat's facial nerve.

    PubMed

    Hwang, Kun; Kim, Sun Goo; Kim, Dae Joong; Lee, Chang Hyun

    2005-11-01

    The aim of this study is to compare regeneration of the severed nerves that were repaired by laser welding with those repaired by microsurgical suturing and evaluate the value in use of laser nerve welding in the head and neck area. In 12 rats the buccal branches of the facial nerves on the both sides were transected, and CO2 laser welding of the epineurium was performed on the right side and microsurgical suture technique was applied on the left side. In six rats Cholera Toxin B Subunit (CTb) was injected in the epineurium distal to the nerve anastomosis site at postoperative week 4. Another six rats were treated exactly in the same way in postoperative week 8. Six normal rats were used as controls. Intact facial nerve was observed after injection of CTb as well. Neurons of facial nuclei labeled positively by CTb were detected immunohistochemically, and the numbers were counted. CTb-positive neurons in the control group were 1311 +/- 258 (n = 6). CTb-positive neurons in the group (n = 6) with laser nerve welding were 1174 +/- 122 in postoperative week 4 and 1562 +/- 565 in postoperative week 8. CTb-positive neurons in the group (n = 6) with microsurgical suture were 1066 +/- 89 in postoperative week 4 and 1443 +/- 531 in postoperative week 8. CTb-positive neurons were seen significantly more in the group with laser welding than in the group with microsurgical suture in postoperative week (P = 0.028), but there was not much difference in postoperative week 8 (P = 0.463). None of 12 rats showed dehiscence at the nerve anastomosis done by laser welding. This study shows that nerve regeneration is more apparent in the nerve repaired by laser welding than in that repaired by microsurgical suture. PMID:16327562

  9. Inhomogeneous derangement of cardiac autonomic nerve control in diabetic rats.

    PubMed

    Sanyal, Shamarendra Nath; Arita, Makoto; Ono, Katsushige

    2002-03-01

    The present study compared autonomic nervous function in Kob [Spontaneously Diabetic, Bio-Breeding (BB)] rats with control Wistar rats to determine the development of cardiac neuropathy in diabetic rats. Telemetric ECG signals were obtained from an ECG radio-transmitter placed in a dorsal subcutaneous pouch of male Kob and Wistar rats for 30min every 6h at a sample rate of 5kHz. Heart rate (HR) and HR variability (HRV) were analyzed in each group by power spectrograms obtained by a fast Fourier transform algorithm. RR interval, total power (TP), low frequency (LF) power (0.04-0.67 Hz), high frequency (HF) power (0.79-1.48 Hz) and LF/HF ratio were also measured. The Kob rats had lower HRV than the control Wistar rats; HR, TP, and HF power, but not the LF/HF ratio, in the Kob rats were significantly lower than those of the control rats (p<0.001). However, in the Kob rats the response of these parameters to a muscarinic antagonist (atropine: 2mg/kg) was left intact, but their response to a beta-adrenergic antagonist (propranolol: 4mg/kg) was impeded. Autonomic nervous control of HR in spontaneously diabetic rats was inhomogeneously deranged in terms of the balance in sympathetic and parasympathetic tone, not only in the baseline condition, but also in the regulatory systems, including postsynaptic receptor function. PMID:11922279

  10. Genetic analyses of fancy rat-derived mutations.

    PubMed

    Kuramoto, Takashi; Yokoe, Mayuko; Yagasaki, Kayoko; Kawaguchi, Tatsuya; Kumafuji, Kenta; Serikawa, Tadao

    2010-01-01

    To collect rat mutations and increase the value of the rat model system, we introduced fancy-derived mutations to the laboratory and carried out genetic analyses. Six fancy rats were shipped from a fancy rat colony in the USA and used as founders. After initial crosses with a laboratory strain, TM/Kyo or PVG/Seac, inbreeding started and 6 partially inbred lines, including 2 sublines, were produced as Kyoto Fancy Rat Stock (KFRS) strains. During inbreeding, we isolated 9 mutations: 5 coat colors, American mink (am), Black eye (Be), grey (g), Pearl (Pel), siamese (sia); 1 coat pattern, head spot (hs); 2 coat textures, Rex (Re), satin (sat); and an ear pinnae malformation, dumbo (dmbo). Genetic analyses mapped 7 mutations to particular regions of the rat chromosomes (Chr): am to Chr 1, sia to Chr 1, sat to Chr 3, Re to Chr 7, g to Chr 8, dmbo to Chr 14, and hs to Chr 15. Candidate gene analysis revealed that a missense mutation in the tyrosinase gene, Ser79Pro, was responsible for sia. From mutant phenotypes and mapping positions, it is likely that all mutations isolated in this study were unique to the fancy rat. These findings suggest that fancy rat colonies are a good source for collecting rat mutations. The fancy-derived mutations, made available to biomedical research in the current study, will increase the scientific value of laboratory rats. PMID:20484848

  11. Sex differences in the stress response in SD rats.

    PubMed

    Lu, Jing; Wu, Xue-Yan; Zhu, Qiong-Bin; Li, Jia; Shi, Li-Gen; Wu, Juan-Li; Zhang, Qi-Jun; Huang, Man-Li; Bao, Ai-Min

    2015-05-01

    Sex differences play an important role in depression, the basis of which is an excessive stress response. We aimed at revealing the neurobiological sex differences in the same study in acute- and chronically-stressed rats. Female Sprague-Dawley (SD) rats were randomly divided into 6 groups: chronic unpredictable mild stress (CUMS), acute foot shock (FS) and controls, animals in all 3 groups were sacrificed in proestrus or diestrus. Male SD rats were randomly divided into 3 groups: CUMS, FS and controls. Comparisons were made of behavioral changes in CUMS and control rats, plasma levels of corticosterone (CORT), testosterone (T) and estradiol (E2), and of the hypothalamic mRNA-expression of stress-related molecules, i.e. estrogen receptor α and β, androgen receptor, aromatase, mineralocorticoid receptor, glucocorticoid receptor, corticotropin-releasing hormone, arginine vasopressin and oxytocin. CUMS resulted in disordered estrus cycles, more behavioral and hypothalamic stress-related molecules changes and a stronger CORT response in female rats compared with male rats. Female rats also showed decreased E2 and T levels after FS and CUMS, while male FS rats showed increased E2 and male CUMS rats showed decreased T levels. Stress affects the behavioral, endocrine and the molecular response of the stress systems in the hypothalamus of SD rats in a clear sexual dimorphic way, which has parallels in human data on stress and depression. PMID:25687843

  12. Decreased hepatobiliary transport of methotrexate in adjuvant arthritis rats.

    PubMed

    Achira, M; Totsuka, R; Fujimura, H; Kume, T

    2002-12-01

    1. We investigated the difference in hepatobiliary transport of methotrexate in normal and adjuvant arthritis (AA) rats and substantiated the expression level of multidrug resistance-associated protein 2 (MRP2) in the liver. 2. Biliary clearance of methotrexate in normal and AA rats was calculated from plasma concentrations and biliary excretion following intravenous infusion and hepatic uptake clearance was estimated from an integration plot using methotrexate concentrations in plasma and liver. 3. Biliary clearance of methotrexate in AA rats was 2.30 +/- 0.23 ml min(-1) kg(-1) (mean SD) and significantly lower than in normal rats (8.42 +/- 0.81 ml min(-1) kg(-1)). The uptake clearance of methotrexate in AA rats was also lower than in normal rats (0.138 versus 0.278 ml min(-1) g liver(-1)). 4. MRP2 in the liver was detected by fluorescein isothiocyanate-labelled antibody and visualized using a confocal laser microscope system. The expression level of MRP2 in AA rats was very low compared with normal rats, indicating a down-regulation in AA rats. 5. In conclusion, biliary clearance of methotrexate was decreased due to the lower activities in both uptake and canalicular secretion, suggesting that several active transporters in the liver, including MRP2, are down-regulated in AA rats. PMID:12593762

  13. Hypotension- and osmotically induced thirst in old Brown Norway rats

    PubMed Central

    Thunhorst, Robert L.; Beltz, Terry G.; Johnson, Alan Kim

    2009-01-01

    Compared to young cohorts, old rats drink less water in response to several thirst-inducing stimuli. In these experiments, we characterized water drinking in response to hypotension and cellular dehydration in young (4 mo), middle-aged adult (12 mo) and old (29–30 mo) male Brown Norway rats. We injected the vasodilator, minoxidil as an intravenous bolus in a range of doses (0–20 mg/kg), so that drinking responses could be compared at equivalent reductions of arterial pressure. Old rats had greatly diminished reflex tachycardia and became significantly more hypotensive after minoxidil compared with young and middle-aged rats. When compared at equivalent reductions of arterial pressure, old rats drank one-third as much as middle-aged rats, and one-fifth as much as young rats. In addition, there were age-related deficits in drinking in response to a range of administered loads of sodium (0.15–2 M NaCl, 2 ml/100 g body wt). Urinary excretion of water and sodium in response to the loads was equivalent across ages. Both middle-aged and old rats were less able than young rats to repair their water deficits after sodium loading, attributable almost entirely to their reduced drinking responses compared with young rats. Lastly, age-related declines in drinking appeared to be more severe in response to hypotension than in response to cellular dehydration. PMID:19420291

  14. Study of the effects of ozone in emphysematous rats

    SciTech Connect

    Dormans, J.A.; van Bree, L.; Boere, A.J.; Marra, M.; Rombout, P.J.

    1989-01-01

    The effects of short-term exposure to ozone on control and elastase-induced emphysematous rats were examined to investigate whether emphysema would change the pulmonary susceptibility to oxidant air pollution. Emphysema was induced in rats after a single intratracheal instillation of 0.2 IU elastase/g body weight. Histologically, panacinar emphysema was apparent at 2, 4, 8, and 16 wk, that is, the total duration of the experiment. The diagnosis was confirmed by morphometry: the mean linear intercepts (MLI) of elastase-treated rats were significantly increased at all observation times, whereas the internal surface areas (ISA) of the elastase-treated rats were significantly decreased. In addition, pulmonary function tests provided supportive evidence for the diagnosis of emphysema. Respiratory system compliance and functional residual capacity showed a significant increase in elastase-treated rats. No differences in inspiratory capacity or in forced vital capacity between control rats and elastase-treated rats were observed. The above data are indicative for a rat model for elastase-induced emphysema. Short-term exposure to ozone of elastase-treated rats revealed panacinar emphysema, including an inflammatory response in the centroacinar region. No differences in MLI as well as in ISA between ozone-exposed rats (with or without emphysema) and their respective controls were observed. Short-term exposure to ozone induced an identical, significant increase in protein content, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, and glutathione peroxidase activities in lungs of normal and emphysematous rats. Moreover, these results strongly suggest that emphysematous rats are not more susceptible to ozone than nonemphysematous rats.

  15. Metabolic responses to head-down suspension in hypophysectomized rats

    NASA Technical Reports Server (NTRS)

    Woodman, C. R.; Tipton, C. M.; Evans, J.; Linderman, J. K.; Gosselink, K.; Grindeland, R. E.

    1993-01-01

    Rats exposed to head-down suspension (HDS) exhibit reductions in maximal O2 consumption (VO2max) and atrophy of select hindlimb muscles. This study tested the hypothesis that an endocrine-deficient rat exposed to HDS would not exhibit reductions in VO2max or hindlimb muscle mass. Hypophysectomized (HYPX) and sham-operated (SHAM) rats were tested for VO2max before and after 28 days of HDS or cage control (CC) conditions. No significant reductions in VO2max were observed in HYPX rats. In contrast, SHAM-HDS rats exhibited a significant reduction in absolute (-16%) and relative (-29%) measures of aerobic capacity. Time course experiments revealed a reduction in VO2max in SHAM-HDS rats within 7 days, suggesting that cardiovascular adjustments to HDS occurred in the 1st wk. HDS was associated with atrophy of the soleus (-42%) in SHAM rats, whereas HYPX rats exhibited atrophy of the soleus (-36%) and plantaris (-13%). SHAM-HDS rats had significantly lower (-38%) soleus citrate synthase activities per gram muscle mass than SHAM-CC, but no significant differences existed between HYPX-HDS and -CC rats. HDS rats had an impaired ability to thermoregulate, as indicated by significantly greater temperature increases per unit run time, compared with their CC counterparts. Pretreatment plasma epinephrine levels were significantly lower in HYPX than in SHAM rats. Norepinephrine concentration was similar for all groups except HYPX-HDS, in which it was significantly higher. HDS had no significant effect on thyroxine or triiodothyronine. SHAM-HDS rats had significantly lower concentrations of testosterone and growth hormone.(ABSTRACT TRUNCATED AT 250 WORDS).

  16. Dysfunctional play and dopamine physiology in the Fischer 344 rat

    PubMed Central

    Siviy, Stephen M.; Crawford, Cynthia A.; Akopian, Garnik; Walsh, John P.

    2011-01-01

    Juvenile Fischer 344 rats are known to be less playful than other inbred strains, although the neurobiological substrate(s) responsible for this phenotype is uncertain. In the present study, Fischer 344 rats were compared to the commonly used outbred Sprague-Dawley strain on several behavioral and physiological parameters in order to ascertain whether the lack of play may be related to compromised activity of brain dopamine (DA) systems. As expected, Fischer 344 rats were far less playful than Sprague-Dawley rats, with Fischer 344 rats less likely to initiate playful contacts with a playful partner and less likely to respond playfully to these contacts. We also found that Fischer 344 rats showed less of a startle response and greater pre-pulse inhibition (PPI), especially at higher pre-pulse intensities. The increase in PPI seen in the Fischer 344 rat could be due to reduced DA modulation of sensorimotor gating and neurochemical measures were consistent with Fischer 344 rats releasing less DA than Sprague-Dawley rats. Fast scan cyclic voltammetry (FSCV) revealed Fischer 344 rats had less evoked DA release in dorsal and ventral striatal brain slices and high-performance liquid chromatography revealed Fischer 344 rats to have less DA turnover in the striatum and prefrontal cortex. We also found DA-dependent forms of cortical plasticity were deficient in the striatum and prefrontal cortex of the Fischer 344 rat. Taken together, these data indicate that deficits in play and enhanced PPI of Fischer 344 rats may be due to reduced DA modulation of corticostriatal and mesolimbic/mesocortical circuits critical to the execution of these behaviors. PMID:21335036

  17. Effects of rat cytomegalovirus on the nervous system of the early rat embryo.

    PubMed

    Sun, Xiuning; Guan, YingJun; Li, Fengjie; Li, Xutong; Wang, Xiaowen; Guan, Zhiyu; Sheng, Kai; Yu, Li; Liu, Zhijun

    2012-08-01

    The purpose of the study was to investigate the impact of rat cytomegalovirus (RCMV) infection on the development of the nervous system in rat embryos, and to evaluate the involvement of Wnt signaling pathway key molecules and the downstream gene neurogenin 1 (Ngn1) in RCMV infected neural stem cells (NSCs). Infection and control groups were established, each containing 20 pregnant Wistar rats. Rats in the infection group were inoculated with RCMV by intraperitoneal injection on the first day of pregnancy. Rat E20 embryos were taken to evaluate the teratogenic rate. NSCs were isolated from E13 embryos, and maintained in vitro. We found: 1) Poor fetal development was found in the infection group with low survival and high malformation rates. 2) The proliferation and differentiation of NSCs were affected. In the infection group, NSCs proliferated more slowly and had a lower neurosphere formation rate than the control. The differentiation ratio from NSCs to neurons and glial cells was significantly different from that of the control, showed by immunofluorescence staining. 3) Ngn1 mRNA expression and the nuclear β-catenin protein level were significantly lower than the control on day 2 when NSCs differentiated. 4) The Morris water maze test was performed on 4-week pups, and the infected rats were found worse in learning and memory ability. In a summary, RCMV infection caused abnormalities in the rat embryonic nervous system, significantly inhibited NSC proliferation and differentiation, and inhibited the expression of key molecules in the Wnt/β-catenin signaling pathway so as to affect NSCs differentiation. This may be an important mechanism by which RCMV causes embryonic nervous system abnormalities. PMID:22899431

  18. A Low-Protein Diet Enhances Angiotensin II Production in the Lung of Pregnant Rats but Not Nonpregnant Rats

    PubMed Central

    Gao, Haijun; Tanchico, Daren Tubianosa; Yallampalli, Uma; Yallampalli, Chandrasekhar

    2016-01-01

    Pulmonary angiotensin II production is enhanced in pregnant rats fed a low-protein (LP) diet. Here we assessed if LP diet induces elevations in angiotensin II production in nonpregnant rats and whether Ace expression and ACE activity in lungs are increased. Nonpregnant rats were fed a normal (CT) or LP diet for 8, 12, or 17 days and timed pregnant rats fed for 17 days from Day 3 of pregnancy. Plasma angiotensin II, expressions of Ace and Ace2, and activities of these proteins in lungs, kidneys, and plasma were measured. These parameters were compared among nonpregnant rats or between nonpregnant and pregnant rats fed different diets. Major findings are as follows: (1) plasma angiotensin II levels were slightly higher in the LP than CT group on Days 8 and 12 in nonpregnant rats; (2) expression of Ace and Ace2 and abundance and activities of ACE and ACE2 in lungs, kidneys, and plasma of nonpregnant rats were unchanged by LP diet except for minor changes; (3) the abundance and activities of ACE in lungs of pregnant rats fed LP diet were greater than nonpregnant rats, while those of ACE2 were decreased. These results indicate that LP diet-induced increase in pulmonary angiotensin II production depends on pregnancy. PMID:27195150

  19. Effect of Post-Weaning Individual Housing on Autonomic Responses in Male Rats to Sexually Receptive Female Rats

    PubMed Central

    Inagaki, Hideaki; Kuwahara, Masayoshi; Tsubone, Hirokazu

    2013-01-01

    Post-weaning individual housing induces significant alterations in the reward system of adult male rats presented with sexually receptive female rats. In this study, we examined the effects of post-weaning individual housing on autonomic nervous activity in adult male rats during encounters with sexually receptive female rats to assess whether different affective states depending on post-weaning housing conditions are produced. Changes in heart rate and spectral parameters of heart rate variability indicated that in post-weaning individually housed male rats, both sympathetic and parasympathetic activity increased with no change in the sympathovagal balance, while in post-weaning socially housed male rats, both sympathetic and parasympathetic activity decreased with a predominance of parasympathetic activity. These two patterns of shifts in sympathovagal balances closely resembled changes in autonomic nervous activity with regard to classical appetitive conditioning in male rats. The autonomic changes in male rats housed individually after weaning corresponded to changes associated with the reward-expecting state evoked by the conditioned stimulus, and the autonomic changes observed in male rats housed socially after weaning corresponded to changes associated with the reward-receiving state evoked by the unconditioned stimulus. These results suggest that different affective states were induced in adult male rats during sexual encounters depending on male–male social interactions after weaning. The remarkable change caused by post-weaning individual housing may be ascribed to alteration of the reward system during sexual encounters induced by deficiency of intermale social communication after weaning. PMID:23903058

  20. Effect of post-weaning individual housing on autonomic responses in male rats to sexually receptive female rats.

    PubMed

    Inagaki, Hideaki; Kuwahara, Masayoshi; Tsubone, Hirokazu

    2013-01-01

    Post-weaning individual housing induces significant alterations in the reward system of adult male rats presented with sexually receptive female rats. In this study, we examined the effects of post-weaning individual housing on autonomic nervous activity in adult male rats during encounters with sexually receptive female rats to assess whether different affective states depending on post-weaning housing conditions are produced. Changes in heart rate and spectral parameters of heart rate variability indicated that in post-weaning individually housed male rats, both sympathetic and parasympathetic activity increased with no change in the sympathovagal balance, while in post-weaning socially housed male rats, both sympathetic and parasympathetic activity decreased with a predominance of parasympathetic activity. These two patterns of shifts in sympathovagal balances closely resembled changes in autonomic nervous activity with regard to classical appetitive conditioning in male rats. The autonomic changes in male rats housed individually after weaning corresponded to changes associated with the reward-expecting state evoked by the conditioned stimulus, and the autonomic changes observed in male rats housed socially after weaning corresponded to changes associated with the reward-receiving state evoked by the unconditioned stimulus. These results suggest that different affective states were induced in adult male rats during sexual encounters depending on male-male social interactions after weaning. The remarkable change caused by post-weaning individual housing may be ascribed to alteration of the reward system during sexual encounters induced by deficiency of intermale social communication after weaning. PMID:23903058

  1. Generation and characterization of rat liver stem cell lines and their engraftment in a rat model of liver failure

    PubMed Central

    Kuijk, Ewart W.; Rasmussen, Shauna; Blokzijl, Francis; Huch, Meritxell; Gehart, Helmuth; Toonen, Pim; Begthel, Harry; Clevers, Hans; Geurts, Aron M.; Cuppen, Edwin

    2016-01-01

    The rat is an important model for liver regeneration. However, there is no in vitro culture system that can capture the massive proliferation that can be observed after partial hepatectomy in rats. We here describe the generation of rat liver stem cell lines. Rat liver stem cells, which grow as cystic organoids, were characterized by high expression of the stem cell marker Lgr5, by the expression of liver progenitor and duct markers, and by low expression of hepatocyte markers, oval cell markers, and stellate cell markers. Prolonged cultures of rat liver organoids depended on high levels of WNT-signalling and the inhibition of BMP-signaling. Upon transplantation of clonal lines to a Fah−/− Il2rg−/− rat model of liver failure, the rat liver stem cells engrafted into the host liver where they differentiated into areas with FAH and Albumin positive hepatocytes. Rat liver stem cell lines hold potential as consistent reliable cell sources for pharmacological, toxicological or metabolic studies. In addition, rat liver stem cell lines may contribute to the development of regenerative medicine in liver disease. To our knowledge, the here described liver stem cell lines represent the first organoid culture system in the rat. PMID:26915950

  2. The local effect of octreotide on mechanical pain sensitivity is more sensitive in DA rats than DA.1U rats.

    PubMed

    Yao, Fan-Rong; Wang, Hui-Sheng; Guo, Yuan; Zhao, Yan

    2016-02-01

    A recent study by the authors indicated that major histocompatibility complex (MHC) genes are associated with the differences in basal pain sensitivity and in formalin model between Dark-Agouti (DA) and novel congenic DA.1U rats, which have the same genetic background as DA rats except for the u alleles of MHC. The objective of the present study is to investigate whether there is a difference in the pristane-induced arthritis (PIA) model and local analgesic effect of octreotide (OCT) between DA and DA.1U rats. The hindpaw mechanical withdrawal threshold (MWT) and heat withdrawal latency (HWL) were observed. The C unit firings of the tibial nerve evoked by non-noxious and noxious toe movements were recorded by electrophysiological methods in normal and PIA models in DA and DA.1U rats before and after local OCT administration. The expression of somatostatin receptor 2A (SSTR2A) was observed by immunohistochemistry. The results demonstrate that DA rats have a higher mechanical sensitivity than DA.1U rats after PIA. Local OCT administration significantly elevated MWT in DA rats under normal and PIA sate, but not in DA.1U rats. The electrophysiological experiments showed OCT significantly attenuated the firings of C units evoked by non-noxious and noxious stimulation in DA rats more than those in DA.1U rats both in normal and PIA states. In addition, the expression of SSTR2A in the dorsal horn of the spinal cord was significantly higher in DA than in DA.1U rats. All of the findings suggest a higher local analgesic effect of OCT in DA rats than DA.1U rats, which might be associated with the MHC genes. PMID:26606866

  3. Diseases Transmitted by Man's Worst Friend: the Rat.

    PubMed

    Fox, James G

    2015-12-01

    Historically, the rat has been considered a scourge to mankind, for example, rats infected with the plague bacillus that caused the Black Death, which accounted for millions of deaths in Europe during the Middle Ages. At least three pandemics (in the 5th and 6th, 8th through 14th, and 19th through 21st centuries) of plague ravaged civilizations, and the disease undoubtedly plagued humankind prior to recorded history. Also, numerous other diseases are spread to humans by rats; thus, a quote from Hans Zinsser's text Rats, Lice, and History, "Man and rat will always be pitted against each other as implacable enemies," conveys the general revulsion that society holds for the wild rat. PMID:27337284

  4. Prevention of anemia alleviates heart hypertrophy in copper deficient rats

    SciTech Connect

    Lure, M.D.; Fields, M.; Lewis, C.G. Univ. of Maryland, College Park Georgetown Univ., Washington, DC )

    1991-03-11

    The present investigation was designed to examine the role of anemia in the cardiomegaly and myocardial pathology of copper deficiency. Weanling rats were fed a copper deficient diet containing either starch (ST) or fructose (FRU) for five weeks. Six rats consuming the FRU diet were intraperitoneally injected once a week with 1.0 ml/100g bw of packed red blood cells (RBC) obtained from copper deficient rats fed ST. FRU rats injected with RBC did not develop anemia. Additionally, none of the injected rats exhibited heart hypertrophy or gross pathology and all survived. In contrast, non-injected FRU rats were anemic, exhibited severe signs of copper deficiency which include heart hypertrophy with gross pathology, and 44% died. Maintaining the hematocrit with RBC injections resulted in normal heart histology and prevented the mortality associated with the fructose x copper interaction. The finding suggest that the anemia associated with copper deficiency contributes to heart pathology.

  5. Relationship of roof rat population indices with damage to sugarcane

    USGS Publications Warehouse

    Lefebvre, Lynn W.; Engeman, Richard M.; Decker, David G.; Holler, Nicholas R.

    1989-01-01

    Roof rats (Rattus rattus) cause substantial damage to sugarcane in South Florida (Samol 1972; Lefebvre et al. 1978, 1985). Accurate estimates of roof rat populations in sugarcane fields would be useful for determining when to to treat a field to control roof rats and for assessing the efficacy of control. However, previous studies have indicated that roof rats exhibit trap shyness, which makes capture-recapture population estimates difficult (Lefebvre et al. 1978, 1985; Holler et al., 1981). Until trapping methods are sufficiently improved to allow accurate population estimates, indices of population size that relate to damage need to be developed. The objectives of our study were to examine the relationship of several indices of roof rat populations to the percentage of sugarcane stalks damaged at harvest; to determine which population index would be most useful for sugarcane growers; and to report on a test of several types of live traps for roof rats.

  6. Estrogenic regulation of Leydig cell development in the rat

    SciTech Connect

    Myers, R.B.

    1989-01-01

    Initial studies demonstrated that treatment of male rats with estradiol for a period of four days resulted in a reduction in {sup 3}H-thymidine incorporation of isolated interstitial cells. Furthermore, {sup 3}H-thymidine incorporation in interstitial cells of 33 day old rats was inhibited by the addition of estradiol in vitro. Subsequent studies were performed in the ethylene dimethanesulphonate (EDS) treated rat. Leydig cells were rapidly destroyed after EDS administration as determined by hCG binding, steroid synthesis and morphological studies. A significant finding was the production of 5{alpha}-androstane-3{alpha},17{beta}-diol by regeneration Leydig cells of the EDS treated rat. In subsequent studies, rats received daily treatment with estradiol and/or hCG/LH after EDS treatment. Estradiol treatment had no effect on Leydig cell degeneration. Leydig cell regeneration, however, did not occur in the estradiol treated rat.

  7. Discriminative and reinforcing stimulus properties of music for rats.

    PubMed

    Otsuka, Y; Yanagi, J; Watanabe, S

    2009-02-01

    We trained rats to discriminate music by Bach from that by Stravinsky using operant conditioning. The rats successfully learned the discrimination and transferred their discrimination to novel music by the same artists. Then, we trained rats on concurrent-chain schedule in which the terminal links were associated with different music, Bach or Stravinsky. The rats did not show strong preference for either style of music, although one subject showed a preference for Bach and another subject preferred Stravinsky. Finally, we examined the validity of the concurrent-chain procedure as a method of preference measurement with conspecific vocalization evoked by an aversive experience. Most of the rats preferred white noise to the conspecific vocalization. Therefore, music has a discriminative stimulus property but not a clear reinforcing property for rats. PMID:19022358

  8. Remyelination of demyelinated rat axons by transplanted mouse oligodendrocytes

    SciTech Connect

    Crang, A.J.; Blakemore, W.F. )

    1991-01-01

    The injection of the gliotoxic agent ethidium bromide (EB) into spinal white matter produces a CNS lesion in which it is possible to investigate the ability of transplanted glial cells to reconstruct a glial environment around demyelinated axons. This study demonstrates that transplanted mouse glial cells can repopulate EB lesions in rats provided tissue rejection is controlled. In X-irradiated EB lesions in cyclosporin-A-treated rats, mouse oligodendrocytes remyelinated rat axons and, together with mouse astrocytes, re-established a CNS environment. When transplanted into nonirradiated EB lesions in nude rats, mouse glial cells modulated the normal host repair by Schwann cells to remyelination by oligodendrocytes. In both X-irradiated and non-irradiated EB lesions, transplanted mouse glial cells behaved similarly to isogenic rat glial cell transplants. These findings indicate that the cell-cell interactions involved in reconstruction of a glial environment are common to both mouse and rat.

  9. Taurine in the osmoregulation of the Brattleboro rat

    SciTech Connect

    Nieminen, M.J.; Tuomisto, L.; Solatunturi, E.; Eriksson, L.; Paasonen, M.K.

    1988-01-01

    The function of taurine in mammalian osmoregulation was studied in the Brattleboro rat with hereditary hypothalamic diabetes insipidus (DI). DI rats are chronically dehydrated because of their inability to synthesize vasopressin. One day of water deprivation did not affect the water balance in rats with normal vasopressin synthesis, whereas DI rats were markedly dehydrated and lost considerably body weight. Taurine content and /sup 3/H-taurine accumulation by platelets were significantly higher in DI rats, with a further increase after one day of water deprivation. In DI rats, water deprivation also evoked a clear taurine increase in skeletal muscle and in the brain. These findings indicate that taurine has an osmoregulatory function in mammals.

  10. Characterization of rat prothymocyte with monoclonal antibodies recognizing rat lymphocyte membrane antigenic determinants

    SciTech Connect

    Hale, M.L.; Greiner, D.L.; McCarthy, K.F.

    1987-01-01

    Utilizing the technique of fluorescence-activated cell sorting and monoclonal antibodies directed at rat membrane antigens, various subpopulations of Lewis bone marrow cells were isolated and subsequently transfused into sublethally irradiated, histocompatible NBr recipient rats by either intravenous of intrathymic inoculation. Recipient rats were sacrificed and cell suspensions from thymus and other lymphoid tissue were examined for the presence of the RT7.1 marker on Lewis thymus-derived lymphocytes by fluorescence-activated cell analysis. From these studies, the population of Lewis bone-marrow cells that could resonstitute T cells in the NBr rats was found to be Ox-22 negative, Ox-7 positive, W3/13 positive, and Ox-18 positive. Further analysis characterized the prothymocyte as being Ox-7 upper 20% positive and W3/13 weakly positive. In addition, this marrow-cell population was able to protect lethally irradiated Lewis rats (9.5 GY) in 30-day survival tests. These studies have indicated that the prothymocyte either has been derived from the Ox-22 negative, Ox-7 upper 20% positive, and W3/13 positive marrow cells or, like the hematopoietic stem cell, this cell has also been characterized by this phenotype.

  11. The Metabolism and Toxicity of Menthofuran in Rat Liver Slices and in Rats

    PubMed Central

    Khojasteh, S. Cyrus; Oishi, Shimako; Nelson, Sidney D.

    2010-01-01

    Menthofuran is a monoterpene present in mint plants that is oxidized by mammalian cytochrome P450 (CYP)1 to hepatotoxic metabolites. Evidence has been presented that p-cresol and other unusual oxidative products are metabolites of menthofuran in rats, and that p-cresol may be responsible in part for the hepatotoxicity caused by menthofuran (Madyastha and Raj, Drug Metabolism and Disposition 20, 295–301, 1992). In the present study, several oxidative metabolites of menthofuran were characterized in rat and human liver microsomes, and in rat liver slices exposed to cytotoxic concentrations of menthofuran. Metabolites that were identified were monohydroxylation products of the furanyl and cyclohexyl groups, mintlactones and hydroxymintlactones, a reactive γ-ketoenal, and a glutathione conjugate. A similar spectrum of metabolites was found in urine 24 hr after the administration of hepatotoxic doses of menthofuran to rats. In no case was p-cresol (or any of the other reported unusual oxidative metabolites of menthofuran) detected above background concentrations that were well below concentrations of p-cresol that cause cytotoxicity in rat liver slices. Thus, the major metabolites responsible for the hepatotoxic effects of menthofuran appear to be a γ-ketoenal and/or epoxides formed by oxidation of the furan ring. PMID:20945912

  12. An electrophoretic study of urinary protein in the rat.

    PubMed

    SELLERS, A L; ROBERTS, S; RASK, I; SMITH, S; MARMORSTON, J; GOODMAN, H C

    1952-05-01

    The nature of the proteins present in the urine of the normal rat has been investigated by electrophoretic analysis and by fractional precipitation of these proteins by ammonium sulfate. Components similar to serum alpha- and beta-globulin constitute the major portion of the urinary protein in both male and female rats. Following the intraperitoneal injection of renin, a massive proteinuria occurs. The proteins excreted are similar in proportion and electric mobility to those of normal rat serum. PMID:14927799

  13. AN ELECTROPHORETIC STUDY OF URINARY PROTEIN IN THE RAT

    PubMed Central

    Sellers, Alvin L.; Roberts, Sidney; Rask, Irene; Smith, Stephen; Marmorston, Jessie; Goodman, Howard C.

    1952-01-01

    The nature of the proteins present in the urine of the normal rat has been investigated by electrophoretic analysis and by fractional precipitation of these proteins by ammonium sulfate. Components similar to serum α- and β-globulin constitute the major portion of the urinary protein in both male and female rats. Following the intraperitoneal injection of renin, a massive proteinuria occurs. The proteins excreted are similar in proportion and electric mobility to those of normal rat serum. PMID:14927799

  14. The oncogenic action of ionizing radiation on rat skin

    SciTech Connect

    Burns, F.J.; Garte, S.J.

    1990-01-01

    An extensive experiment involving approximately 400 rats exposed to the neon ion beam at the Bevalac in Berkeley, CA and to electrons is nearing completion. Progress is described in three areas corresponding to the specific aims of the proposal: (1) carcinogenesis and DNA strand breaks in rat skin following exposure by the neon ions or electrons; (2) oncogene activation in radiation-induced rat skin cancers; (3) DNA strand breaks in the epidermis as a function of radiation penetration. 59 refs., 4 tabs.

  15. Mutagenicity of comfrey (Symphytum Officinale) in rat liver.

    PubMed

    Mei, N; Guo, L; Fu, P P; Heflich, R H; Chen, T

    2005-03-14

    Comfrey is a rat liver toxin and carcinogen that has been used as a vegetable and herbal remedy by humans. In order to evaluate the mechanisms underlying its carcinogenicity, we examined the mutagenicity of comfrey in the transgenic Big Blue rat model. Our results indicate that comfrey is mutagenic in rat liver and the types of mutations induced by comfrey suggest that its tumorigenicity results from the genotoxicity of pyrrolizidine alkaloids in the plant. PMID:15726100

  16. Induction by degraded carrageenan of colorectal tumors in rats.

    PubMed

    Ashi, K W; Inagaki, T; Fujimoto, Y; Fukuda, Y

    1978-03-01

    Degraded carrageenan derived from the red seaweed Eucheuma spinosum was given to Sprague-Dawley rats through the diet, in drinking water or by stomach tube for up to 24 months. Carrageenan-induced squamous cell carcinomas, adenocarcinomas and adenomas in the colorectum were observed. Some rats had metastases to the regional lymph nodes of squamous cell carcinomas. These results show that degraded carrageenan is carcinogenic to the colorectum of the rat. PMID:647659

  17. Optical coherence tomography of the rat cochlea

    NASA Astrophysics Data System (ADS)

    Wong, Brian J.; de Boer, Johannes F.; Park, Boris H.; Chen, Zhongping; Nelson, J. Stuart

    2000-10-01

    Optical coherence tomography (OCT) was used to image the internal structure of a rat cochlea (ex vivo). Immediately following sacrifice, the temporal bone of a Sprague-Dawley rat was harvested. Axial OCT cross sectional images (over regions of interest, 1 X 1 mm-2 X 8 mm) were obtained with a spatial resolution of 10 - 15 micrometers . The osseous borders of the lateral membranous labyrinth overlying the cochlea and the scala vestibuli, media, and tympani, which were well demarcated by the modiolus, Reissner's and the basilar membranes, were clearly identified. OCT can be used to image internal structures in the cochlea without violating the osseous labyrinth using simple surgical exposure of the promontory, and may potentially be used to diagnose inner ear pathology in vivo in both animal and human subjects labyrinth.

  18. Vapor Inhalation of Alcohol in Rats

    PubMed Central

    Gilpin, Nicholas W.; Richardson, Heather N.; Cole, Maury; Koob, George F.

    2008-01-01

    Alcohol dependence constitutes a neuroadaptive state critical for understanding alcoholism, and various methods have been utilized to induce alcohol dependence in animals, one of which is alcohol vapor exposure. Alcohol vapor inhalation provides certain advantages over other chronic alcohol exposure procedures that share the ultimate goal of producing alcohol dependence in rats. Chronic alcohol vapor inhalation allows the experimenter to control the dose, duration, and pattern of alcohol exposure. Also, this procedure facilitates testing of somatic and motivational aspects of alcohol dependence. Chronic exposure to alcohol vapor produces increases in alcohol-drinking behavior, increases in anxiety-like behavior, and reward deficits in rats. Alcohol vapor inhalation as a laboratory protocol is flexible, and the parameters of this procedure can be adjusted to accommodate the specific aims of different experiments. This unit describes the options available to investigators using this procedure for dependence induction, when different options are more or less appropriate, and the implications of each. PMID:18634001

  19. Oxidative stress in normal and diabetic rats.

    PubMed

    Torres, M D; Canal, J R; Pérez, C

    1999-01-01

    Parameters related to oxidative stress were studied in a group of 10 Wistar diabetic rats and 10 control rats. The levels of total erythrocyte catalase activity in the diabetic animals were significantly (p<0.001) greater than the control levels. The diabetic animals presented an amount of vitamin E far greater (p<0.0001) than the controls, as was also the case for the vitaminE/polyunsaturated fatty acid (PUFA) and vitaminE/linoleic acid (C18:2) ratios. Greater vitaminE/triglyceride (TG) ratio, however, appeared in the control group. The corresponding vitamin A ratios (vitaminA/TG, vitaminA/PUFA, vitaminA/C 18:2) were higher in the control group. Our work corroborates the findings that fatty acid metabolism presents alterations in the diabetes syndrome and that the antioxidant status is affected. PMID:10523056

  20. Purified Rabies Vaccine (Suckling Rat Brain Origin)

    PubMed Central

    Lavender, J. F.

    1970-01-01

    A 10% suckling rat brain rabies vaccine free from encephalitogenic activity was prepared and inactivated with 1:8,000 beta-propiolactone (BPL), or ultraviolet light, or a combination of ultraviolet light and BPL, or 1% phenol. Potency was excellent in all samples, with the exception of the phenolized product which was marginal. A purified suckling rat brain (SRB) vaccine prepared by zonal centrifugation and inactivated with 1:8,000 BPL contained about 0.01 the amount of protein nitrogen of the unpurified 10% SRB vaccine. This purified product passed the National Institutes of Health potency test for rabies vaccine after administration of a quantity equivalent to a standard 10% brain suspension. PMID:5456012

  1. Longevity of exercising obese hypertensive rats.

    PubMed

    Booth, F W; MacKenzie, W F; Seider, M J; Gould, E W

    1980-10-01

    The purpose of this study was to determine whether daily running lengthens the life-span of animals dying prematurely due to cardiovascular disease. We used a strain of rat that is genetically hypertensive and obese and is reported to develop atherosclerosis (Exp. Mol. Pathol. 19: 53--60, 1973). These animals were divided into three groups consisting of runners exercised daily on treadmills from an early age life, food-restricted sedentary rats, and libitum eaters that were sedentary. This latter group had significantly higher average daily food intakes and body weights than either of the other two groups. The average life-span of both sedentary groups was significantly longer than the running group. Runners had a greater frequency of focal myocardial necrosis, but atherosclerosis was absent in all three groups. We speculate that daily running may have accentuated the development of factor s that may have contributed to the early death of runners. PMID:7440277

  2. Testosterone and muscle hypertrophy in female rats

    NASA Technical Reports Server (NTRS)

    Kuhn, F. E.; Max, S. R.

    1985-01-01

    The effects of chronic treatment with testosterone propionate (TP) on compensatory muscle hypertropy in female rats are examined. The 48 female rats were placed in one of four test groups: (1) no overload (synergist removal), no TP, (2) overload, no TP, (3) no overload + TP, and (4) overload + TP. The technique used to administer the TP is described. The preparation of the plantaris muscle, the analysis of pyruvate oxidation and the determination of malate and lactate dehydrogenases and the noncollogen protein are explained. The results which reveal the effect of overload and TP on body weight, noncollogen protein concentration, lactate and malate dehydrogenase activities, and pyruvate oxidation are presented and discussed. It is concluded that in terms of body weight, protein content, pyruvate, glycolysis, and oxidative metabolisms chronic TP treatments do not change compensatory muscle hypertropy.

  3. Central auditory conduction time in the rat.

    PubMed

    Shaw, N A

    1990-01-01

    Central conduction time is the time for an afferent volley to traverse the central pathways of a sensory system. In the present study, central auditory conduction time (CACT) was calculated for the rat, the first such formal measurement in any animal. Brainstem auditory evoked potentials (BAEPs) were recorded simultaneously with the primary response of the auditory cortex (P1). The latency of wave II of the BAEP, which arises in the cochlear nucleus, was subtracted from that of P1. This yielded a mean CACT of 6.6 ms. The results confirm a previous theoretical estimate that CACT in the rat is at least twice as long as central somatosensory conduction time. PMID:2311700

  4. Odor aversion learning by the rat fetus.

    PubMed

    Smotherman, W P

    1982-11-01

    Rat fetuses were exposed to an odor stimulus on day 20 of gestation via amniotic injection and then injected with LiCl. In a CER paradigm, 10 day old pups were trained to approach an anesthetized dam in a runway for suckling reinforcement. When running speeds had stabilized the odor stimulus experienced in-utero was introduced into the test chamber. This odor took on aversive properties as a function of its pairing with LiCl, as evidenced by a decrease in running speed on CER trials and increases in the number of trials that were terminated because pups failed to traverse the runway. These data indicate that the fetal rat is capable of odor aversion learning. PMID:6296892

  5. Extensive exchange of rat liver microsomal phospholipids.

    PubMed

    Zilversmit, D B; Hughes, M E

    1977-08-15

    Liver microsomal fractions were prepared from rats injected with a single dose of choline [14C]methylchloride or with single or multiple doses of 32Pi. Exchangeability of microsomal phospholipids was determined by incubation with an excess of mitochondria and phospholipid exchange proteins derived from beef heart, beef liver or rat liver. Labeled phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidylinositol were found to act as a single pool and were 85--95% exchangeable in 1--2h. High latencies of mannose-6-phosphate phosphohydrolase activities and impermeability of microsomes to EDTA proved that phospholipid exchange proteins did not have access to the intracisternal space. If microsomal membranes are largely composed of phospholipid bilayers, the experiments suggest that one or more of the phospholipid classes in microsomal membranes undergo rapid translocation between the inner and outer portions of the bilayer. PMID:889827

  6. DNA topoisomerases from rat liver: physiological variations.

    PubMed Central

    Duguet, M; Lavenot, C; Harper, F; Mirambeau, G; De Recondo, A M

    1983-01-01

    Besides the nicking-closing (topoisomerase I) activity, an ATP-dependent DNA topoisomerase is present in rat liver nuclei. The enzyme, partially purified, is able to catenate in vitro closed DNA circles in a magnesium-dependent, ATP-dependent, histone H1-dependent reaction, and to decatenate in vitro kinetoplast DNA networks to yield free minicircles in a magnesium-dependent and ATP-dependent reaction. It is largely similar to other eukaryotic type II topoisomerases in its requirements, and presumably belongs to this class of enzymes. Type I and type II activities were measured in rat liver nuclei as a function of regenerating time after partial hepatectomy: type I activity was not significantly changed during this process. In contrast, type II activity was considerably increased, suggesting a possible involvement of the enzyme in DNA replication. Images PMID:6298730

  7. Secretin: specific binding to rat brain membranes

    SciTech Connect

    Fremeau, R.T. Jr.; Jensen, R.T.; Charlton, C.G.; Miller, R.L.; O'Donohue, T.L.; Moody, T.W.

    1983-08-01

    The binding of (/sup 125/I)secretin to rat brain membranes was investigated. Radiolabeled secretin bound with high affinity (KD . 0.2 nM) to a single class of noninteracting sites. Binding was specific, saturable, and reversible. Regional distribution studies indicated that the specific binding was greatest in the cerebellum, intermediate in the cortex, thalamus, striatum, hippocampus, and hypothalamus, and lowest in the midbrain and medulla/pons. Pharmacological studies indicated that only secretin, but not other peptides, inhibits binding of (/sup 125/I)secretin with high affinity. Also, certain guanine nucleotides inhibited high affinity binding. These data indicate that rat brain membranes possess high affinity binding sites specific for secretin and that with the use of (/sup 125/I) secretin the kinetics, stoichiometry, specificity, and distribution of secretin receptors can be directly investigated.

  8. Proline transport in rat kidney mitochondria.

    PubMed

    Atlante, A; Passarella, S; Pierro, P; Quagliariello, E

    1994-02-15

    Proline transport in rat kidney mitochondria was investigated both by using isotopic techniques and by spectroscopic measurements, in which proline metabolism was essentially allowed to occur. Widely used criteria for demonstrating the occurrence of carrier-mediated transport were successfully applied in both cases. Differences found in the Km and Vmax values, in pH and temperature dependence of proline transport, and in the inhibitor sensitivity demonstrate the existence of two separate translocators for proline in rat kidney mitochondria, i.e., the proline uniporter and the proline/glutamate antiporter. Efflux of glutamate via glutamate/OH- translocator following proline uptake by mitochondria was experimentally ruled out. Discussion is also made of the possible role of such translocators in proline metabolism and in the putative proline/glutamate shuttle. PMID:7906935

  9. Influence of spaceflight on rat skeletal muscle

    NASA Technical Reports Server (NTRS)

    Martin, Thomas P.; Edgerton, V. Reggie; Grindeland, Richard E.

    1988-01-01

    The effect of a 7-day spaceflight (aboard NASA's SL-3) on the size and the metabolism of single fibers from several rat muscles was investigated along with the specificity of these responses as related to the muscle type and the size of fibers. It was found that the loss of mass after flight was varied from 36 percent in the soleus to 15 percent in the extensor digitorum longus. Results of histochemical analyses showed that the succinate dehydrogenase (SDH) activity in muscles of flight-exposed rats was maintained at the control levels, whereas the alpha-glycerol phosphate dehydrogenase (GPD) activity was either maintained or increased. The analyses of the metabolic profiles of ATPase, SDH, and GPD indicated that, in some muscles, there was an increase in the poportion of fast oxidative-glycolytic fibers.

  10. Loudness scaling in rats and chinchillas.

    PubMed

    Pierrel-Sorrentino, R; Raslear, T G

    1980-08-01

    Chinchillas and rats were trained on operant discriminations in which the discriminative stimuli were two different sound pressure levels of a 4-kHz tone. Two or more of these two-intensity discriminations were used at each of three levels of discriminability: high, medium, and low. For any given level, each of the stimulus pairs used differed in decibel separation but were similar in loudness-unit differences calculated from a power function. Different groups of animals trained on stimuli separated by equal numbers of loudness units produced equivalent performances at each of the three levels of discriminability. It is concluded that loudness growth for both of these species, as for man, is well described by a power function (Stevens' law). For the chinchilla the exponent is .25, and for the rat it is .35. PMID:7410633

  11. Interactions of amiodarone with digoxin in rats.

    PubMed Central

    Braunschweig, J.; Stäubli, M.; Studer, H.

    1987-01-01

    1. The influence of oral amiodarone treatment on the blood and tissue concentrations of digoxin was investigated in the anaesthetized rat by use of unlabelled and [3H]-digoxin. 2. Amiodarone diminished the total body clearance and the apparent volume of digoxin distribution by 60%. This reduction was due to a 50% reduction of the hepatobiliary clearance, whereas the renal clearance did not change. 3. Amiodarone treatment increased blood, myocardial and skeletal muscle [3H]-digoxin concentrations by 200% indicating passive equilibration between blood and these tissues, and resulting in unaltered tissue to blood ratios. In contrast, the liver concentration increased by 70% only and the liver to blood ratio therefore decreased under amiodarone treatment. 4. It is concluded that the hepatobiliary elimination of digoxin is decreased in amiodarone-treated rats compared to controls and is responsible for the increased levels of blood and tissue glycoside. PMID:3427268

  12. Microclimate in two types of rat cages.

    PubMed

    Hirsjärvi, P A; Väliaho, T U

    1987-04-01

    The microclimate in two types of rat cages (a Makrolon type IV with a solid floor and a stainless steel cage with a wire mesh floor (five rats per cage)) placed in the same macro-environment was compared. The temperature, relative humidity and ammonia concentration in the cages were measured twice a day for 8 days. The cages were cleaned every 4 days. The greatest difference between the cage types was in the ammonia build-up. In Makrolon cages the ammonia concentration never reached 5 ppm, whereas in steel cages it showed a constant increase and already exceeded the threshold limit for man (25 ppm for 8 h per day) on the third day after cleaning. PMID:3599880

  13. Inner Retinal Oxygen Delivery and Metabolism in Streptozotocin Diabetic Rats

    PubMed Central

    Wanek, Justin; Teng, Pang-yu; Blair, Norman P.; Shahidi, Mahnaz

    2014-01-01

    Purpose. The purpose of the study is to report global measurements of inner retinal oxygen delivery (DO2_IR) and oxygen metabolism (MO2_IR) in streptozotocin (STZ) diabetic rats. Methods. Phosphorescence lifetime and blood flow imaging were performed in rats 4 (STZ/4wk; n = 10) and 6 (STZ/6wk; n = 10) weeks following injection of STZ to measure retinal arterial (O2A) and venous (O2V) oxygen contents and total retinal blood flow (F). DO2_IR and MO2_IR were calculated from measurements of F and O2A and of F and the arteriovenous oxygen content difference, respectively. Data in STZ rats were compared to those in healthy control rats (n = 10). Results. Measurements of O2A and O2V were not significantly different among STZ/4wk, STZ/6wk, and control rats (P ≥ 0.28). Likewise, F was similar among all groups of rats (P = 0.81). DO2_IR measurements were 941 ± 231, 956 ± 232, and 973 ± 243 nL O2/min in control, STZ/4wk, and STZ/6wk rats, respectively (P = 0.95). MO2_IR measurements were 516 ± 175, 444 ± 103, and 496 ± 84 nL O2/min in control, STZ/4wk, and STZ/6wk rats, respectively (P = 0.37). Conclusions. Global inner retinal oxygen delivery and metabolism were not significantly impaired in STZ rats in early diabetes. PMID:24550355

  14. Bilirubin UDP-glucuronyltransferase activity of wistar rat kidney.

    PubMed

    Foliot, A; Christoforov, B; Petite, J P; Etienne, J P; Housset, E; Dubois, M

    1975-08-01

    Wistar rat kidneys have been shown to possess a bilirubin glucuronyltransferase (BGT) activity capable of conjugating about 3/5 of the total pool of unconjugated bilirubin within 48 h of being grafted to Gunn rat hosts. Bilirubin conjugated by the kidney is taken up by the liver and excreted in the bile. Except when the bile duct is ligated, no conjugated bilirubin appears in the plasma or urine. Renal BGT activity is about 1/20th of the hepatic activity on a weight basis in Wistar rats. The Gunn rat's hyperbilirubinemia probably causes an induction of the renal enzyme since its activity doubles in 48 h. PMID:808968

  15. The effect of magnesium depletion on thyroid function in rats

    SciTech Connect

    Hsu, J.M.; Root, A.W.; Duckett, G.E.; Smith, J.C. Jr.; Yunice, A.A.; Kepford, G.

    1984-08-01

    The effects of dietary magnesium (Mg) depletion on thyroid function were studied in young male rats. The rats were fed a semipurified diet containing either 12 ppm Mg (deficient rats) or 662 ppm Mg (control rats) for 14 to 28 days. Results showed that the Mg-deficient rats had decreased body weight gain, lowered concentrations of plasma thyroxine (T4) and Mg, but increased weight of the thyroid gland when expressed in proportion to the body weight (milligrams/100 g). There was no difference in the accumulation (uptake) of 131I, 24 hours after Na131I injection, between the Mg-deficient and Mg-supplemented rats. The protein-bound 131I (PB131I) level and the ratio of PB131I to total 131I in plasma was significantly reduced in Mg-deficient rats. Serum thyroid-stimulating hormone (TSH) levels after thyrotropin-releasing hormone injection (TRH, 50 ng/100 g body weight) increased fivefold at 30 minutes, but declined to near the basal level at 2 hours in both groups. No consistent difference in TSH response was observed between the two treatments. Serum T4 response to TRH challenge was significantly reduced in Mg-deficient as compared to Mg-adequate rats at all time intervals. The reduction of T4 level could be due to an impaired T4 synthesis or release in Mg-deficient rats.

  16. Favism: divicine hemotoxicity in the rat.

    PubMed

    McMillan, D C; Jollow, D J

    1999-10-01

    Favism is an acute hemolytic anemia known to occur in susceptible individuals who ingest fava beans. Susceptibility to favism is conferred by a genetic deficiency in erythrocytic glucose-6-phosphate dehydrogenase (G6PD) activity. Although the fava bean pyrimidine aglycones, divicine and isouramil, have been implicated in the onset of favism in humans, the lack of a well-defined experimental animal model for favism has hampered progress in elucidating the mechanism underlying hemotoxicity. We have examined whether a favic-like response could be provoked in G6PD-normal rats treated with synthetic divicine. Intraperitoneal administration of divicine to rats preloaded with 51Cr-tagged erythrocytes resulted in a severe, dose-dependent decrease in blood radioactivity (TD50 approximately 0.5 mmol/kg) within 24 h. The increased rate of removal of blood radioactivity was accompanied by a rapid decline in reduced glutathione levels in the blood, decreased hematocrits, marked hemoglobinuria, splenic enlargement, and reticulocytosis. In vitro exposure of 51Cr-tagged red cells to divicine before their re-administration to isologous rats also resulted in a sharp, concentration-dependent decrease in erythrocyte survival in vivo (TC50 approximately 1.5 mM), and these divicine-damaged red cells were removed from the circulation by the spleen. These data demonstrate that a favic response can be induced in G6PD-normal rats treated with divicine, and that hemolytic activity can be reproduced in isolated red cells under conditions that will allow a direct examination of the mechanism underlying this hemotoxicity. PMID:10543033

  17. Excretion of bisphenol A into rat milk.

    PubMed

    Okabayashi, Ken; Watanabe, Toshi

    2010-03-01

    Bisphenol A (BPA), an endocrine-disrupting chemical, is widely used in the production of polycarbonate plastic and epoxy resins. This study analyzed the BPA concentration in rat milk, in order to assess the risk of BPA transfer to the offspring via milk. The rats ingested BPA by oral administration or by drinking the water in a polycarbonate bottle, and the milk samples were collected using an automated experimental milker. The BPA concentration in the samples of milk, drinking water, and food was analyzed by LC/MS. In the case of milk samples obtained from rats injected with BPA at 2, 4, 8, and 24 h prior to milking, the BPA concentrations were 0.462 +/- 0.182 ppm, 0.138 +/- 0.0185 ppm, 0.080 +/- 0.0197 ppm, and 0.0232 +/- 0.0051 ppm, respectively. Also, in the cases of the water sample left in polycarbonate bottle and the milk sample obtained from rats provided it as drinking water, the concentrations of BPA were 0.000332 +/- 0.00015 ppm and 0.0184 +/- 0.0050 ppm, respectively. The results indicate that the BPA administered to the dams was transferred to their milk, and that BPA concentration in milk was higher at the early period after the single bolus dose. Additionally, these results reveal that sequential elution of BPA from polycarbonate containers in a much diluted form would undergo bioaccumulation in dams and likely be transferred to pups via milk in a much concentrated form. PMID:20163291

  18. Sexual reflexes in male and female rats.

    PubMed

    Chung, S K; McVary, K T; McKenna, K E

    1988-12-01

    A novel preparation for the study of male and female sexual function in anesthetized, acutely spinalized rats is reported. In both sexes, the coitus reflex (the neuromuscular concomitants of sexual climax) could be elicited by mechanical stimulation of the distal urethra. It is concluded that the spinal sexual circuitry is essentially similar in both sexes and that the coitus reflex is generated by a hormone-insensitive spinal pattern generator and is triggered by a simple peripheral stimulus. PMID:3205410

  19. Chemical Renal Denervation in the Rat

    SciTech Connect

    Consigny, Paul M. Davalian, Dariush; Donn, Rosy Hu, Jie; Rieser, Matthew Stolarik, DeAnne

    2013-12-03

    Introduction: The recent success of renal denervation in lowering blood pressure in drug-resistant hypertensive patients has stimulated interest in developing novel approaches to renal denervation including local drug/chemical delivery. The purpose of this study was to develop a rat model in which depletion of renal norepinephrine (NE) could be used to determine the efficacy of renal denervation after the delivery of a chemical to the periadventitial space of the renal artery. Methods: Renal denervation was performed on a single renal artery of 90 rats (n = 6 rats/group). The first study determined the time course of renal denervation after surgical stripping of a renal artery plus the topical application of phenol in alcohol. The second study determined the efficacy of periadventitial delivery of hypertonic saline, guanethidine, and salicylic acid. The final study determined the dose–response relationship for paclitaxel. In all studies, renal NE content was determined by liquid chromatography–mass spectrometry. Results: Renal NE was depleted 3 and 7 days after surgical denervation. Renal NE was also depleted by periadventitial delivery of all agents tested (hypertonic saline, salicylic acid, guanethidine, and paclitaxel). A dose response was observed after the application of 150 μL of 10{sup −5} M through 10{sup −2} M paclitaxel. Conclusion: We developed a rat model in which depletion of renal NE was used to determine the efficacy of renal denervation after perivascular renal artery drug/chemical delivery. We validated this model by demonstrating the efficacy of the neurotoxic agents hypertonic saline, salicylic acid, and guanethidine and increasing doses of paclitaxel.

  20. Toxicity evaluation of crankcase oil in rats

    PubMed Central

    Arise, R.O.; Tella, A.C.; Akintola, A.A.; Akiode, S.O.; Malomo, S.O.

    2012-01-01

    The aim of this study was to investigate the effect of crankcase oil on the cellular and functional integrity of rat skin. Thirty (30) rats were randomly grouped into six viz groups A-F. Group A (base-line control) received 2 ml of distilled water. 2.5 %, 5.0 %, 7.5 %, and 10.0 % v/v of the crankcase oil were prepared using unused oil as solvent and 2 ml of the concentrations were topically administered to groups C-F respectively for seven consecutive days. Group B served as positive control and received 2 ml of the unused oil. The rats were sacrificed 24 hours after the last administration, and blood and part of the skin were collected. Alkaline phosphatase (ALP), acid phosphatase (ACP), superoxide dismutase (SOD) and malondialdehyde level in the blood and skin samples collected were evaluated. Elemental analysis of the crankcase oil was also carried out. The result revealed high lead, iron and chromium levels. Blood lead concentration of rats was significantly (P<0.05) high after seven days of administration. ALP level in skin and serum increased significantly (P<0.05) with the concentration of crankcase oil. There was a significant decrease (P<0.05) in skin ACP activity while it increased significantly (P<0.05) in the serum. Similar results were observed in the SOD levels of the serum and the skin. The level increased significantly (P<0.05) in groups D-F when compared with controls. The MDA concentration of both serum and skin were significantly (P<0.05) elevated. This suggests toxic potential of used lubricating oil and its potential predisposition to cancer. PMID:27366138

  1. D-RATS 2011: RAFT Protocol Overview

    NASA Technical Reports Server (NTRS)

    Utz, Hans

    2011-01-01

    A brief overview presentation on the protocol used during the D-RATS2011 field test for file transfer from the field-test robots at Black Point Lava Flow AZ to Johnson Space Center, Houston TX over a simulated time-delay. The file transfer actually uses a commercial implementation of an open communications standard. The focus of the work lies on how to make the state of the distributed system observable.

  2. Rabbiteye blueberry prevents osteoporosis in ovariectomized rats

    PubMed Central

    2014-01-01

    Objective It has been forecasted that the rabbiteye blueberry could inhibit osteoporosis. However, the inhibition and prevention of osteoporosis via rabbiteye blueberry are still elusive. This study was aim to evaluate the anti-osteoporosis effects of rabbiteye blueberry in ovariectomized rats. Methods Thirty rats were randomly divided into three groups of ten rats each as follows: sham-operated group (SG), ovariectomized model control group (OMG), and ovariectomized rabbiteye blueberry treatment group (OBG). The blood mineral levels, the alkaline phosphatase (ALP) activity, and osteoprotegerin (OPG) level were determined. The expression analyses of type I collagen, integrin-β1, and focal adhesion kinase (FAK) were performed. Besides, the bone mineral density (BMD) and bone histomorphometry (BH) were measured. Results The ALP activity in SG and OBG was significantly lower than that in OMG. For the OPG level, the significant increase of OPG level in OBG was indicated compared with the other groups. The mRNA expression levels of type I collagen, integrin-β1, and FAK in OMG were significantly lower than those in other groups. The BMD in OMG were all significantly lower than those in SG and OBG. For BH, blueberry significantly improved the trabecular bone volume fraction, trabecular thickness, mean trabecular bone number, and bone formation rate, and decreased the trabecular separation, the percent of bone resorption perimeter, and mean osteoclast number in OBG compared with OMG. Conclusions The rabbiteye blueberries had an effective inhibition in bone resorption, bone loss, and reduction of bone strength of ovariectomized rats and could improve the BMD, osteogenic activity, and trabecular bone structure. PMID:25102951

  3. Pharmacokinetic Profile of Spectinomycin in Rats

    PubMed Central

    Madhura, Dora Babu; Lee, Richard; Meibohm, Bernd

    2014-01-01

    Short Summary Following intravenous (IV) administration, the pharmacokinetics of spectinomycin in rats was found to be on par with its profile in other mammalian species including humans with respect to its overall excretion and half-life at effective concentrations. This study, however, indicates that a small fraction of the spectinomycin dose is retained in peripheral tissues for a prolonged period of time at low concentrations. PMID:24020122

  4. Characterization of prostanoid receptors on rat neutrophils.

    PubMed Central

    Wise, H; Jones, R L

    1994-01-01

    1. The effects of various prostanoid agonists have been compared on the increase in intracellular free calcium ([Ca2+]i) and the aggregation reaction of rat peritoneal neutrophils induced by N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP). 2. Prostaglandin E2 (PGE2) and the specific IP-receptor agonist, cicaprost, both inhibited the FMLP-induced increase in [Ca2+]i (IC50 33 nM and 18 nM respectively) and the FMLP-induced aggregation reaction (IC50 5.6 nM and 7.9 nM respectively). PGD2, PGF2 alpha, and the TP-receptor agonist, U 46619, were inactive at the highest concentration tested (1 microM). 3. The EP1-receptor agonist, 17-phenyl-omega-trinor PGE2, and the EP3-receptor agonists, GR 63799X and sulprostone, had no inhibitory effect on FMLP-stimulated rat neutrophils. 4. PGE1 (EP/IP-receptor agonist) and iloprost (IP-receptor agonist) inhibited the FMLP-induced increase in [Ca2+]i with IC50 values of 34 nM and 38 nM respectively. The EP2-receptor agonists, butaprost and misoprostol (1 microM), inhibited both FMLP-stimulated [Ca2+]i and aggregation. However another EP2-receptor agonist, AH 13205, was inactive in both assays. 5. Prostanoid receptors present on rat neutrophils were further characterized by measuring [3H]-adenosine 3':5'-cyclic monophosphate ([3H]-cyclic AMP) accumulation. Only those agonists capable of stimulating [3H]-cyclic AMP accumulation were able to inhibit both FMLP-stimulated [Ca2+]i and aggregation. 6. These results indicate that rat neutrophils possess inhibitory IP and EP-receptors; the relative potencies of PGE2, misoprostol and butaprost are those expected for the EP2-receptor subtype. No evidence for DP, FP, TP or EP1 and EP3-receptors was obtained. PMID:7834211

  5. Oxalic acid decreases calcium absorption in rats

    SciTech Connect

    Weaver, C.M.; Martin, B.R.; Ebner, J.S.; Krueger, C.A.

    1987-11-01

    Calcium absorption from salts and foods intrinsically labeled with /sup 45/Ca was determined in the rat model. Calcium bioavailability was nearly 10 times greater for low oxalate kale, CaCO/sub 3/ and CaCl/sub 2/ than from CaC/sub 2/O/sub 4/ (calcium oxalate) and spinach (high in oxalates). Extrinsic and intrinsic labeling techniques gave a similar assessment of calcium bioavailability from kale but not from spinach.

  6. Purification of rat and human ghrelins.

    PubMed

    Kojima, Masayasu; Hosoda, Hiroshi; Kangawa, Kenji

    2012-01-01

    Small synthetic molecules called growth hormone secretagogues (GHSs) stimulate the release of growth hormone (GH) from the pituitary. They act through the GHS-R, a G-protein-coupled receptor highly expressed in the hypothalamus and pituitary. Using an orphan receptor strategy with a stable cell line expressing GHS-R, we purified endogenous ligands for GHS-R from rat and human stomach and named it "ghrelin," after a word root (ghre) in Proto-Indo-European languages meaning "grow." Ghrelin is a peptide hormone in which the third amino acid, usually a serine but in some species a threonine, is modified by a fatty acid; this modification is essential for ghrelin's activity. The main active form of rat ghrelin is 28-amino acid peptides with n-octanoyl modification. In rat stomach, a second type of ghrelin peptide was purified, identified as des-Gln14-ghrelin. With the exception of the deletion of Gln14, des-Gln14-ghrelin is identical to ghrelin, retaining the n-octanoic acid modification. Des-Gln14-ghrelin is encoded by an mRNA created by alternative splicing of the ghrelin gene. As in the rat, the major active form of human ghrelin is a 28-amino acid peptide with an n-octanoylated Ser3. However, in human stomach, several minor forms of human ghrelin peptides have been isolated. These can be classified into four groups by the type of acylation observed at Ser3 and into two groups by the amino acids in length. The discovery of ghrelin indicates that the release of GH from the pituitary and appetite stimulation might be regulated by ghrelin derived from the stomach. PMID:22975045

  7. Microvascular transplantation of the rat submandibular gland.

    PubMed

    Spiegel, J H; Zhang, F; Levin, D E; Singer, M I; Buncke, H J

    2000-11-01

    Xerostomia results from salivary gland irradiation during treatment of head and neck malignancies. In addition to having difficulty with speech and swallowing, these patients experience loss of taste, dental caries, and chronic fungal infections. The paired submandibular glands provide 70 percent of the normal salivary flow and are difficult to shield during radiation therapy. Another sicca condition, xerophthalmia, may result from facial nerve injury or other medical disorders and results in pain, corneal ulceration, and possible vision loss. Treatment options for xerostomia are limited, and management of xerophthalmia usually focuses on the eyelids, rather than the fundamental problem of inadequate secretory protection. In this study, a rat model for submandibular gland microvascular transplantation was developed to assess the feasibility of salivary tissue transfer. Sixteen rats underwent submandibular gland transplantation from the neck to the groin. Fourteen of these rats underwent microvascular anastomosis of the vascular pedicle. Ten glands were assessed for viability at 4 days after transplantation, and four glands were examined after 7, 10, 14, or 21 days. By gross and histologic examination, 93 percent of transplanted glands showed expected long-term viability after at least 4 postoperative days. Microvascular techniques were shown to be applicable to the transplantation of submandibular gland salivary tissue. This has not previously been shown in a rat model. It is possible that submandibular glands could be transplanted to the eye for treatment of xerophthalmia and out of the neck during irradiation of the head and neck, with subsequent replantation after treatment as a means of preventing permanent xerostomia. PMID:11083564

  8. Activation of rat complement by soluble and insoluble rat IgA immune complexes.

    PubMed

    Rits, M; Hiemstra, P S; Bazin, H; Van Es, L A; Vaerman, J P; Daha, M R

    1988-12-01

    The ability of rat monoclonal IgA, specific for 2,4-dinitrophenyl (DNA), to activate the complement (C) system of the rat was investigated using aggregated IgA or IgA immune complexes (IC). IgA was coated onto a solid phase, and tested for its capacity to bind C3 upon incubation at 37 degrees C in normal rat serum (NRS) in the presence of Mg-EGTA. Binding of C3 was observed dependent on the dose of dimeric (d-), polymeric (p-) and secretory IgA tested. In contrast, little C3 fixation was observed in this system with monomeric (m-) rat IgA or with mouse m- and d-IgA (MOPC315). Soluble and insoluble rat IgA IC were prepared using dinitrophenylated rat serum albumin (DNP8RSA) as antigen (Ag), and assessed for C activation. It was shown that insoluble IC (immune precipitates; IP) containing m-, d- or pIgA of rat origin activate the alternative pathway of rat C, as demonstrated by their capacity to induce C consumption in NRS in the presence of Mg-EGTA. When p- and m-IgA IP were compared for their capacity to activate C, it was found that p-IgA activated C four times as efficiently as m-IgA IP (at 2 mg/ml). Soluble rat IgA IC were prepared in an excess of DNP8RSA, fractionated by gel filtration on Sepharose 6B, and analyzed for C activation and antibody (Ab)/Ag ratio. In contrast to m-IgA IP, soluble m-IgA did not activate C. On the other hand soluble d-IgA IC activated C dependent on their concentration and size: at a concentration of 0.1 mg/ml high-molecular weight d-IgA IC with a high Ab/Ag ratio were four times as efficient as low-molecular weight IC with a low Ab/Ag ratio, and twice as efficient as IP prepared at equivalence. To demonstrate the induction by IgA of the assembly of the terminal membrane attack complex, trinitrophenyl (TNP)-conjugated rat red blood cells (TNP-RRBC) coated with d- or p-IgA were shown to be lysed in NRS in the presence of Mg-EGTA. No lysis of m-IgA-coated TNP-RRBC was observed. The results in this study demonstrate that both soluble and

  9. Obesity-resistant S5B rats showed great cocaine conditioned place preference than the obesity-prone OM rats

    SciTech Connect

    Thanos, P.K.; Wang, G.; Thanos, P.K..; Kim, R.; Cho, J.; Michaelides, M.; Anderson, B.J.; Primeaux, S.D.; Bray, G.A.; Wang, G.-J.; Robinson, J.K.; Volkow, N.D.

    2010-12-01

    Dopamine (DA) and the DA D2 receptor (D2R) are involved in the rewarding and conditioned responses to food and drug rewards. Osborne-Mendel (OM) rats are genetically prone and S5B/P rats are genetically resistant to obesity when fed a high-fat diet. We hypothesized that the differential sensitivity of these two rat strains to natural rewards may also be reflected in sensitivity to drugs of abuse. Therefore, we tested whether OM and S5B/P rats showed a differential preference to cocaine using conditioned place preference (CPP). To also evaluate whether there is specific involvement of the D2R in this differential conditioning sensitivity, we then tested whether the D2R agonist bromocriptine (BC) would differentially affect the effects of cocaine in the two strains. OM and S5B/P rats were conditioned with cocaine (5 or 10 mg/kg) in one chamber and saline in another for 8 days. Rats were then tested for cocaine preference. The effects of BC (0.5, 1, 5, 10, 20 mg/kg) on cocaine preference were then assessed in subsequent test sessions. OM rats did not show a significant preference for the cocaine-paired chamber on test day. Only the S5B/P rats showed cocaine CPP. Later treatment with only the highest dose of BC resulted in reduced cocaine CPP in S5B/P rats when treated with 5 mg/kg cocaine and in OM rats treated with 10 mg/kg cocaine. Our results indicated that obesity-resistant S5B rats showed greater cocaine CPP than the obesity-prone OM rats. These findings do not support a theory of common vulnerability for reinforcer preferences (food and cocaine). However, they show that BC reduced cocaine conditioning effects supporting at least a partial regulatory role of D2R in conditioned responses to drugs.

  10. Rat Model of Parkes Weber Syndrome.

    PubMed

    Bojakowski, Krzysztof; Janusz, Gabriela; Grabowska, Iwona; Zegrocka-Stendel, Oliwia; Surowiecka-Pastewka, Agnieszka; Kowalewska, Magdalena; Maciejko, Dorota; Koziak, Katarzyna

    2015-01-01

    The Parkes Weber syndrome is a congenital vascular malformation, characterized by varicose veins, arterio-venous fistulas and overgrown limbs. No broadly accepted animal model of Parkes Weber syndrome has been described. We created side-to-side arterio-venous fistula between common femoral vessels with proximal non-absorbable ligature on common femoral vein limiting the enlargement of the vein diameter in Wistar rats. Contralateral limb was sham operated. Invasive blood pressure measurements in both iliac and inferior cava veins were performed in rats 30 days after fistula creation. Tight circumference and femoral bone length were measured. Histopathology and morphology of soleus muscle, extensor digitorum longus muscle, and the common femoral vessel were analyzed. 30 days following arterio-venous fistula creation, a statistically significant elevation of blood pressure in common iliac vein and limb overgrowth was observed. Limb enlargement was caused by muscle overgrowth, varicose veins formation and bone elongation. Arterio-venous fistula with proximal outflow limitation led to significant increase of femoral vein circumference and venous wall thickness. Our study indicates that the described rat model mimics major clinical features characteristic for the human Parkes Weber syndrome: presence of arterio-venous fistula, venous hypertension and dilatation, varicose veins formation, and the limb hypertrophy. We reveal that limb overgrowth is caused by bone elongation, muscle hypertrophy, and venous dilatation. The newly established model will permit detailed studies on the mechanisms underlying the disease and on the efficacy of novel therapeutic strategies for the Parkes Weber syndrome treatment. PMID:26217941

  11. Rat Model of Parkes Weber Syndrome

    PubMed Central

    Bojakowski, Krzysztof; Janusz, Gabriela; Grabowska, Iwona; Zegrocka-Stendel, Oliwia; Surowiecka-Pastewka, Agnieszka; Kowalewska, Magdalena; Maciejko, Dorota; Koziak, Katarzyna

    2015-01-01

    The Parkes Weber syndrome is a congenital vascular malformation, characterized by varicose veins, arterio-venous fistulas and overgrown limbs. No broadly accepted animal model of Parkes Weber syndrome has been described. We created side-to-side arterio-venous fistula between common femoral vessels with proximal non-absorbable ligature on common femoral vein limiting the enlargement of the vein diameter in Wistar rats. Contralateral limb was sham operated. Invasive blood pressure measurements in both iliac and inferior cava veins were performed in rats 30 days after fistula creation. Tight circumference and femoral bone length were measured. Histopathology and morphology of soleus muscle, extensor digitorum longus muscle, and the common femoral vessel were analyzed. 30 days following arterio-venous fistula creation, a statistically significant elevation of blood pressure in common iliac vein and limb overgrowth was observed. Limb enlargement was caused by muscle overgrowth, varicose veins formation and bone elongation. Arterio-venous fistula with proximal outflow limitation led to significant increase of femoral vein circumference and venous wall thickness. Our study indicates that the described rat model mimics major clinical features characteristic for the human Parkes Weber syndrome: presence of arterio-venous fistula, venous hypertension and dilatation, varicose veins formation, and the limb hypertrophy. We reveal that limb overgrowth is caused by bone elongation, muscle hypertrophy, and venous dilatation. The newly established model will permit detailed studies on the mechanisms underlying the disease and on the efficacy of novel therapeutic strategies for the Parkes Weber syndrome treatment. PMID:26217941

  12. Generation of Transgenic Rats Using Lentiviral Vectors.

    PubMed

    Reichardt, Holger M; Fischer, Henrike J

    2016-01-01

    Transgenesis is a valuable tool with which to study different aspects of gene function in the context of the intact organism. During the last two decades a tremendous number of transgenic animals have been generated, and the continuous improvement of technology and the development of new systems have fostered their widespread application in biomedical research. Generally, transgenic animals are generated by introducing foreign DNA into fertilized oocytes, which can be achieved either by injecting recombinant DNA into the pronucleus or by transferring lentiviral particles into the perivitelline space. While mice remain the favored species in many laboratories, there are a number of applications where the use of rats is advantageous. One such research area is multiple sclerosis. Here, several experimental models are available that are closely mimicking the human disease, and it is possible to induce neuroinflammation by transferring pathogenic T cells which can then be studied by flow cytometry and 2-photon live imaging. Unlike for mice, the development of transgenic rats has encountered some hurdles in the past, e.g., due to a complicated reproductive biology and the frailty of the fertilized oocytes in vitro. In this chapter we provide a protocol describing how we manipulate single cell embryos in our lab in order to efficiently generate transgenic rats in a variety of different strains using lentiviral gene transfer. PMID:25063498

  13. Clodronate prevents immobilization osteopenia in rats.

    PubMed

    Tarvainen, R; Arnala, I; Olkkonen, H; Lappalainen, R; Nevalainen, T; Alhava, E

    1994-12-01

    We investigated the effect of clodronate on immobilization osteopenia (IO) induced by sciatic neurectomy in rats. 100 Wistar female rats were divided into 5 groups of 20 animals each: 1) sham-operated, control group, 2) IO+saline control group, 3) IO+clodronate 3 mg/kg/day, 4) IO+clodronate 10 mg/kg/day, and 5) IO+clodronate 30 mg/kg/day. Clodronate was administered subcutaneously beginning on the day after nerve sectioning. After 7 weeks, the animals were killed and both tibiae were removed. Bone mineral density, ash weight and calcium, phosphorus and magnesium contents of the ash of the tibiae were analyzed. The weight of the rats did not differ between the groups during the experiment. The ash weight of the tibiae decreased by 6.6 percent and the mineral density decreased by 5.1 percent after neurectomy. Clodronate reduced IO in a dose-dependent manner and the highest dose neutralized the effect of neurectomy. The calcium content of the ash decreased after neurectomy as compared to the sham-operated group, and clodronate increased it to the sham-operated level. The bone Ca/P ratio remained normal. PMID:7839852

  14. Fipronil induces CYP isoforms in rats.

    PubMed

    Caballero, M V; Ares, I; Martínez, M; Martínez-Larrañaga, M R; Anadón, A; Martínez, M A

    2015-09-01

    The goal of the present study was to evaluate fipronil effects on the activities of drug metabolizing enzymes in rat liver microsomes. Rats were orally treated with fipronil at doses of 1, 5, 10 and 15 mg/kg bw/day for 6 days. Determinations of cytochrome P450 (CYP) enzyme activities were carried out in hepatic microsomes isolated from treated rats. The activities of some members of CYP2E, CYP1A, CYP2A, CYP2B and CYP3A subfamilies significantly increased after fipronil treatment in a dose-dependent manner as compared to control. The major effects were observed in the O-deethylation of ethoxyresorufin and O-demethylation of methoxyresorufin (reflecting CYP1A1/2 activities), in the O-depenthylation of pentoxyresorufin and 16β-hydroxylation of testosterone (reflecting CYP2B1/2 activities), and in the N-demethylation of erythromycin and 6β-hydroxylation of testosterone (reflecting CYP3A1/2 activities). Immunoblot studies revealed that fipronil increased the apoprotein levels of CYP1A1. Our results suggest that fipronil is an inducer of hepatic phase I CYP enzymes, causing an increased potential to interact with a wide range of xenobiotics or endogenous chemicals that are substrates of the CYP1A, CYP2B and CYP3A subfamilies. Further investigations are required to in vivo evaluate the potential of the metabolite fipronil sulfone as an inducer of phase I CYP enzymes. PMID:26142839

  15. Increased myocardial catalase in rats fed ethanol.

    PubMed Central

    Fahimi, H. D.; Kino, M.; Hicks, L.; Thorp, K. A.; Abelman, W. H.

    1979-01-01

    The effects of chronic intake of dietary ethanol upon catalase, an enzyme capable of metabolizing ethanol, as well as upon myocardial morphology and hemodynamics, were studied in the rat. Ethanol, comprising 36% of dietary calories, administered to rats for 5 weeks, was associated with increased myocardial catalase of 45.9 +/- 3.7 IU/mg protein, compared to 21.0 +/- 1.8 IU/mg protein in pair-fed controls. The enzyme activity remained significantly elevated after 18 weeks of ethanol. Hepatic catalase did not differ in these groups. Parallel cytochemical studies confirmed the increase in myocardial catalase by demonstrating an increase in peroxisomes. Gross and light-microscopic examinations revealed no abnormalities at either 5 or 18 weeks. Remarkably few ultrastructural abnormalities were seen in this material fixed by vascular perfusion. Hemodynamic studies after 5 weeks of ethanol revealed decreased left ventricle systolic pressure and decreased mean arterial pressure but no change in ventricular filling pressure. The possibility of catalase playing a metabolic and potentially protective role in rat myocardium chronically exposed to ethanol is discussed. Images Figure 3 Figure 4-6 Figures 1 and 2 Figures 7 and 8 p[389]-a PMID:474705

  16. Growth hormone aggregates in the rat adenohypophysis

    NASA Technical Reports Server (NTRS)

    Farrington, M.; Hymer, W. C.

    1990-01-01

    Although it has been known for some time that GH aggregates are contained within the rat anterior pituitary gland, the role that they might play in pituitary function is unknown. The present study examines this issue using the technique of Western blotting, which permitted visualization of 11 GH variants with apparent mol wt ranging from 14-88K. Electroelution of the higher mol wt variants from gels followed by their chemical reduction with beta-mercaptoethanol increased GH immunoassayability by about 5-fold. With the blot procedure we found 1) that GH aggregates greater than 44K were associated with a 40,000 x g sedimentable fraction; 2) that GH aggregates were not present in glands from thyroidectomized rats, but were in glands from the thyroidectomized rats injected with T4; 3) that GH aggregates were uniquely associated with a heavily granulated somatotroph subpopulation isolated by density gradient centrifugation; and 4) that high mol wt GH forms were released from the dense somatotrophs in culture, since treatment of the culture medium with beta-mercaptoethanol increased GH immunoassayability by about 5-fold. Taken together, the results show that high mol wt GH aggregates are contained in secretory granules of certain somatotrophs and are also released in aggregate form from these cells in vitro.

  17. Ethanol and blood pressure in rats

    SciTech Connect

    Hatton, D.C.; Edgar, S.; McCarron, D.A. )

    1989-02-09

    Epidemiologists have identified alcohol as a risk factor in hypertension. Attempts to increase blood pressure in rats with chronic alcohol ingestion have met with mixed results. Some investigators have reported increases in blood pressure while others have reported decreases. Most investigators have given alcohol in the drinking water which produced differences in food intake across groups. To control for food intake, Wister rats were simultaneously pair fed a liquid diet with either ethanol as 35% of calories or a control diet using ARF/Israel pair-feeding devices. At 5 weeks of age, animals on ethanol diets had lower systolic blood pressure than control animals (145 (n-19) vs. 121 (n-19) mmHg). There was no difference in weight between ethanol and control animals. The same pattern of results was apparent at 7 weeks (143 (n-13) vs. 119 (n-13) mmHg) and 9 weeks (147 (n-7) vs. 124 (n-7)). The data indicate that ethanol produces hypotension in rats when food intake is controlled.

  18. Associative foundation of causal learning in rats.

    PubMed

    Polack, Cody W; McConnell, Bridget L; Miller, Ralph R

    2013-03-01

    Are humans unique in their ability to interpret exogenous events as causes? We addressed this question by observing the behavior of rats for indications of causal learning. Within an operant motor-sensory preconditioning paradigm, associative surgical techniques revealed that rats attempted to control an outcome (i.e., a potential effect) by manipulating a potential exogenous cause (i.e., an intervention). Rats were able to generate an innocuous auditory stimulus. This stimulus was then paired with an aversive stimulus. The animals subsequently avoided potential generation of the predictive cue, but not if the aversive stimulus was subsequently devalued or the predictive cue was extinguished (Exp. 1). In Experiment 2, we demonstrated that the aversive stimulus we used was in fact aversive, that it was subject to devaluation, that the cue-aversive stimulus pairings did make the cue a conditioned stimulus, and that the cue was subject to extinction. In Experiments 3 and 4, we established that the decrease in leverpressing observed in Experiment 1 was goal-directed instrumental behavior rather than purely a product of Pavlovian conditioning. To the extent that interventions suggest causal reasoning, it appears that causal reasoning can be based on associations between contiguous exogenous events. Thus, contiguity appears capable of establishing causal relationships between exogenous events. Our results challenge the widely held view that causal learning is uniquely human, and suggest that causal learning is explicable in an associative framework. PMID:22562460

  19. Metabolic consequences of methylenecyclopropylglycine poisoning in rats.

    PubMed Central

    Melde, K; Jackson, S; Bartlett, K; Sherratt, H S; Ghisla, S

    1991-01-01

    We describe the effects of methylenecyclopropylglycine in fasted rats. A 75% decrease in the blood glucose concentration and an increase of lactate and pyruvate were observed 6 h after administration of 100 mg of this amino acid/kg. By contrast with the effects reported for hypoglycin [Williamson & Wilson (1965) Biochem. J. 94, 19c-21c], the plasma concentrations of ketone bodies decreased after administration of methylenecyclopropylglycine and the concentrations of branched-chain amino acids in the plasma were increased 6-fold. The oxidation of decanoylcarnitine or of palmitate was nearly completely inhibited in rat liver mitochondria from methylenecyclopropylglycine-poisoned rats. The activities of acetoacetyl-CoA and of 3-oxoacyl-CoA thiolase were decreased to 25% and less than 10% of the controls. There was a pronounced aciduria, due to the excretion of dicarboxylic acids and of oxidation products of branched-chain amino acids. The accumulation of the toxic metabolite methylenecyclopropylformyl-CoA in the mitochondrial matrix was detected after administration of methylenecyclopropylglycine. Similarly we confirmed experimentally that methylenecyclopropylacetyl-CoA accumulates in mitochondria incubated with methylenecyclopropylpyruvate. PMID:2006907

  20. Laser scattering by transcranial rat brain illumination

    NASA Astrophysics Data System (ADS)

    Sousa, Marcelo V. P.; Prates, Renato; Kato, Ilka T.; Sabino, Caetano P.; Suzuki, Luis C.; Ribeiro, Martha S.; Yoshimura, Elisabeth M.

    2012-06-01

    Due to the great number of applications of Low-Level-Laser-Therapy (LLLT) in Central Nervous System (CNS), the study of light penetration through skull and distribution in the brain becomes extremely important. The aim is to analyze the possibility of precise illumination of deep regions of the rat brain, measure the penetration and distribution of red (λ = 660 nm) and Near Infra-Red (NIR) (λ = 808 nm) diode laser light and compare optical properties of brain structures. The head of the animal (Rattus Novergicus) was epilated and divided by a sagittal cut, 2.3 mm away from mid plane. This section of rat's head was illuminated with red and NIR lasers in points above three anatomical structures: hippocampus, cerebellum and frontal cortex. A high resolution camera, perpendicularly positioned, was used to obtain images of the brain structures. Profiles of scattered intensities in the laser direction were obtained from the images. There is a peak in the scattered light profile corresponding to the skin layer. The bone layer gives rise to a valley in the profile indicating low scattering coefficient, or frontal scattering. Another peak in the region related to the brain is an indication of high scattering coefficient (μs) for this tissue. This work corroborates the use of transcranial LLLT in studies with rats which are subjected to models of CNS diseases. The outcomes of this study point to the possibility of transcranial LLLT in humans for a large number of diseases.

  1. Intrathecal Veratridine Administration Increases MAC in Rats

    PubMed Central

    Zhang, Yi; Sharma, Manohar; Eger, Edmond I; Laster, Michael J.; Hemmings, Hugh C.; Harris, R. Adron

    2008-01-01

    Background Results from several studies point to sodium channels as potential mediators of the immobility produced by inhaled anesthetics. We hypothesized that the intrathecal administration of veratridine, a drug that enhances the activity or effect of sodium channels, should increase MAC. Methods We measured the change in isoflurane MAC caused by intrathecal infusion of various concentrations of veratridine into the lumbothoracic subarachnoid space of rats. We compared these result to those obtained from intracerebroventricular infusion. Results As predicted, intrathecal infusion of veratridine increased MAC. The greatest infused concentration (25 μM) also produced neuronal injury in the hind limbs of two rats and decreased the peak effect on MAC. A concentration of 1.6 μM produced the greatest (21%) increase in MAC. Intraventricular infusion of 1.6 and 6.4 μM veratridine did not alter MAC. Rats given 25 μM died. Conclusion Intrathecal administration of veratradine increases MAC of isoflurane, a finding consistent with a role for sodium channels as potential mediators of the immobility produced by inhaled anesthetics. Implications Intrathecal administration of veratridine can increase MAC, presumably by an effect on sodium channels. PMID:18713899

  2. Parathyroid autotransplantation in rats having hypoparathyroidism

    PubMed Central

    Erikoglu, Mehmet; Colak, Bayram; Toy, Hatice; Gurbilek, Mehmet

    2015-01-01

    Re-implantation techniques of extracted parathyroid tissue were developed in order to prevent temporary hypocalcemia. During thyroid surgery; inadvertently removed or devascularized parathyroid gland is usually implanted in the sternocleidomastoid muscle. In this experimental study using rats with hypoparathyroidism, our aim was to investigate whether the excised parathyroid tissue could be seeded in the liver and in the peritoneum, instead of the SCM muscle. In our study, four different groups, each consisting of 10 Wistar albino rats were used (Control group, sternocleidomastoid muscle group, liver group, peritoneum group). Parathyroidectomy was performed and the parathyroid tissue was seeded into the sternocloid mastoid muscle, liver and peritoneum. After 14 days, the rats were sacrificed and levels of calcium, magnesium, phosphorus, alkaline phosphatase and parathyroid hormone were measured in rats’ blood samples. The autotransplanted parathyroid tissue was then excised and examined. In all groups, parathyroid tissues were analyzed histopathologically according to calcification, necrosis, tissue loss, foreign body reaction, inflammation and fibrosis. Regarding Ca, Mg, PO4, ALP; There were no difference between the groups. When we compared control group with the other groups; a difference was observed in the levels of PTH (P<0.05). In pathological examination; regarding tissue loss; there was a difference between liver and peritoneum groups (P<0.05). In our study, we expected better result in plantings inside liver and peritone compared to SKM. However, there were no difference between the groups. PMID:26629152

  3. Distribution of UDPglucuronosyltransferase in rat tissue.

    PubMed Central

    Chowdhury, J R; Novikoff, P M; Chowdhury, N R; Novikoff, A B

    1985-01-01

    UDPglucuronosyltransferase [UDPglucuronate beta-D-glucuronosyltransferase (acceptor-unspecific), EC 2.4.1.17] is a group of enzymes with distinct but partially overlapping substrate specificity. A rabbit antiserum raised against one purified rat liver UDPglycuronosyltransferase isoform was specific for UDPglucuronosyltransferase and recognized all transferase isoforms by immunodiffusion or immunotransblot analysis. The transferase activity toward all substrates was immunoabsorbed from solubilized rat liver microsomes by IgG purified from the antiserum. The purified IgG was used for immunocytochemical localization of UDP-glucuronosyltransferase in rat liver, jejunum, kidney, and adrenal gland. In the liver, UDPglucuronosyltransferase was present exclusively in hepatocytes and was uniformly distributed within all zones of the hepatic lobule. In the jejunum, the transferase was present exclusively in the epithelial cells and showed a progressive increase in concentration from the crypt to the villar tip. In the kidney, the greatest concentration of the transferase was observed in the epithelial cells of the proximal convoluted tubule. Adrenal medullary cells showed intense immunocytochemical staining; the zona glomerulosa and the zona reticularis of the adrenal cortex were more intensely stained than the zona fasciculata. By light microscopy, UDPglucuronosyltransferase was found in the endoplasmic reticulum and nuclear envelope of all the four organs; this was confirmed in the hepatocyte by electron microscopy. The transferase was not observed in mitochondria, Golgi apparatus, lysosomes, peroxisomes, and plasma membrane, even after 3- to 4-fold induction of various substrate-specific UDPglucuronosyltransferase activities. Images PMID:3921970

  4. Cardiac adaptation to endurance exercise in rats.

    PubMed

    Fenning, Andrew; Harrison, Glenn; Dwyer, Dan; Rose'Meyer, Roselyn; Brown, Lindsay

    2003-09-01

    Endurance exercise is widely assumed to improve cardiac function in humans. This project has determined cardiac function following endurance exercise for 6 (n = 30) or 12 (n = 25) weeks in male Wistar rats (8 weeks old). The exercise protocol was 30 min/day at 0.8 km/h for 5 days/week with an endurance test on the 6th day by running at 1.2 km/h until exhaustion. Exercise endurance increased by 318% after 6 weeks and 609% after 12 weeks. Heart weight/kg body weight increased by 10.2% after 6 weeks and 24.1% after 12 weeks. Echocardiography after 12 weeks showed increases in left ventricular internal diameter in diastole (6.39 +/- 0.32 to 7.90 +/- 0.17 mm), systolic volume (49 +/- 7 to 83 +/- 11 miccrol) and cardiac output (75 +/- 3 to 107 +/- 8 ml/min) but not left wall thickness in diastole (1.74 +/- 0.07 to 1.80 +/- 0.06 mm). Isolated Langendorff hearts from trained rats displayed decreased left ventricular myocardial stiffness (22 +/- 1.1 to 19.1 +/- 0.3) and reduced purine efflux during pacing-induced workload increases. 31P-NMR spectroscopy in isolated hearts from trained rats showed decreased PCr and PCr/ATP ratios with increased creatine, AMP and ADP concentrations. Thus, this endurance exercise protocol resulted in physiological hypertrophy while maintaining or improving cardiac function. PMID:14575304

  5. Experimentally induced dentoalveolar ankylosis in rats.

    PubMed

    Hellsing, E; Alatli-Kut, I; Hammarström, L

    1993-03-01

    Dentoalveolar ankylosis is a common complication after replantation of teeth with injured periodontal ligaments. This is a serious complication for the tooth since it leads to progressive root resorption. In young individuals it may also cause infra-occlusion and reduced development of the alveolar process. The purpose of this study was to develop a method applicable to rats in order to follow the effect of systemic and local factors on the development of ankylosis and their possible effect on the length of the functional period of the ankylosed tooth before exfoliation. The maxillary first molars in adult rats were extracted. The periodontal ligaments were devitalized or removed before replantation of the teeth. Dentoalveolar ankylosis was clinically established 2 weeks after replantation. Induction was most reproducible after devitalization or removal of the PDL cells with Dakin's solution and after keeping the rats on a liquid diet up to 3 weeks after replantation. Exfoliation of the teeth usually occurred 6 weeks after replantation. Histological examination showed that the PDL was replaced by bone. The ankylosed teeth showed root resorption to a varying degree. The resorption was in some cases occasionally located in the supra-crestal part of the tooth. A bone-like tissue in the root canal was a rather common finding. In one of the ankylosed teeth cartilage formation was found adjacent to the cementum. PMID:8330940

  6. Quantification of gait in dystonic Gunn rats.

    PubMed

    Chaniary, Kunal D; Baron, Mark S; Rice, Ann C; Wetzel, Paul A; Ramakrishnan, Viswanathan; Shapiro, Steven M

    2009-06-15

    Spontaneously jaundiced Gunn rats exposed to sulfadimethoxine develop bilirubin encephalopathy (kernicterus) with hearing loss and dystonia, closely resembling the human syndrome. We recently characterized the electromyographic activity in this animal model supporting our clinical impression of dystonia. The objective of this study was to develop a simple, non-invasive method to quantify the motor deficits in dystonic rodents. On postnatal day 16, Gunn rats were treated with 100mg/kg of sulfadimethoxine or saline. On postnatal day 31, the ventral view of the animals was videotaped while the animals walked inside a Plexiglas chamber. Individual video frames were reviewed and specific gait parameters including hindlimb spread, step length ratio variability, stance/swing ratio and walking speed were compared between dystonic and non-dystonic jaundiced and non-jaundiced littermates. Data analysis demonstrated statistically significant increases in hindlimb spread and step length ratio variability and decreases in walking speed in dystonic animals as compared to controls. This study demonstrates a valuable technique to objectively characterize dystonia in Gunn rats, which could have wide use for other experimental movement disorders as well. PMID:19464517

  7. Resveratrol Pretreatment Ameliorates TNBS Colitis in Rats

    PubMed Central

    Yildiz, Gulserap; Yildiz, Yuksel; Ulutas, Pinar A.; Yaylali, Aslı; Ural, Muruvvet

    2015-01-01

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disease in humans constituting a major health concern today whose prevalence has been increasing over the world. Production of reactive oxygen species (ROS) and disturbed capacity of antioxidant defense in IBD subjects have been reported. Antioxidants may play a significant role in IBD treatment. This study aimed at evaluating ameliorative effects of intraperitoneal resveratrol pretreatment on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. Thirty five Wistar-Albino female rats were divided equally into five groups. Inflammation was induced by the intrarectal administration of TNBS under anesthesia. Intraperitoneal administration of resveratrol (RSV) at a concentration of 10mg/kg/day for 5 days before the induction of colitis significantly reduced microscopy score and malondialdehyde (MDA) levels and increased glutathione peroxidase (GSH Px) activity compared to TNBS and vehicle groups. Also an insignificant increase in catalase (CAT) activity was observed in the RSV treated group compared to TNBS and vehicle groups. In this paper, the most recent patent on the identification and treatment of IBD was indicated. In conclusion, antioxidant RSV proved to have a beneficial effect on TNBS colitis in rats. In light of these advantageous results, the RSV can be considered as adjuvant agent in IBD treatments. PMID:26246013

  8. Cardioprotection by 6-gingerol in diabetic rats.

    PubMed

    El-Bassossy, Hany M; Elberry, Ahmed A; Ghareib, Salah A; Azhar, Ahmad; Banjar, Zainy Mohammed; Watson, Malcolm L

    2016-09-01

    The current study was conducted to evaluate the effect of 6-gingerol (6G) on cardiac complications in streptozotocin (STZ)-induced diabetic (DM) rats. STZ-induced DM rats (single 50 mg/kg i.p. injection, 15 days prior to drug treatment) or time-matched controls were treated with 6G (75 mg/day route orally). After a further 8 weeks, blood was collected for biochemical analysis and 8-isoprostenol was measured in urine. Cardiac hemodynamics and ECG was assessed. 6G significantly attenuated the increased level of blood glucose in diabetic rats and improved cardiac hemodynamics in including RR interval, max dP/dt, min dP/dt and Tau. In addition, 6G alleviated the elevated ST segment, T amplitude and R amplitude with no significant effect on disturbed levels of adiponectin, TGF-β or 8-isoprostenol induced by diabetes. The results showed that treatment with 6G has an ameliorative effect on cardiac dysfunction induced by diabetes. Which may be not related to its potential antioxidant effect. PMID:27378426

  9. Resveratrol Pretreatment Ameliorates TNBS Colitis in Rats.

    PubMed

    Yildiz, Gulserap; Yildiz, Yuksel; Ulutas, Pinar A; Yaylali, Asl; Ural, Muruvvet

    2015-01-01

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disease in humans constituting a major health concern today whose prevalence has been increasing over the world. Production of reactive oxygen species (ROS) and disturbed capacity of antioxidant defense in IBD subjects have been reported. Antioxidants may play a significant role in IBD treatment. This study aimed at evaluating ameliorative effects of intraperitoneal resveratrol pretreatment on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. Thirty five Wistar-Albino female rats were divided equally into five groups. Inflammation was induced by the intrarectal administration of TNBS under anesthesia. Intraperitoneal administration of resveratrol (RSV) at a concentration of 10mg/kg/day for 5 days before the induction of colitis significantly reduced microscopy score and malondialdehyde (MDA) levels and increased glutathione peroxidase (GSH Px) activity compared to TNBS and vehicle groups. Also an insignificant increase in catalase (CAT) activity was observed in the RSV treated group compared to TNBS and vehicle groups. In this paper, the most recent patent on the identification and treatment of IBD was indicated. In conclusion, antioxidant RSV proved to have a beneficial effect on TNBS colitis in rats. In light of these advantageous results, the RSV can be considered as adjuvant agent in IBD treatments. PMID:26246013

  10. Effects of optimism on motivation in rats.

    PubMed

    Rygula, Rafal; Golebiowska, Joanna; Kregiel, Jakub; Kubik, Jakub; Popik, Piotr

    2015-01-01

    In humans, optimism is a cognitive construct related to motivation; optimists exert effort, whereas pessimists disengage from effort. In this study, using a recently developed ambiguous-cue interpretation (ACI) paradigm we took the unique opportunity to investigate whether "optimism" as a trait is correlated with motivation in rodents. In a series of ACI tests (cognitive bias screening, CBS), we identified rats displaying "pessimistic" and "optimistic" traits. Subsequently, we investigated the trait differences in the motivation of these rats to gain reward and to avoid punishment using a progressive ratio (PR) schedule of reinforcement paradigm. Although "optimistic" and "pessimistic" animals did not differ in their motivation to avoid punishment, the "optimistic" rats were significantly more motivated to gain reward than their "pessimistic" conspecifics. For the first time, we showed an association between cognitive judgment bias and motivation in an animal model. Because both investigated processes are closely related to mental health and wellbeing, our results may be valuable for preclinical modeling of many psychiatric disorders. PMID:25762910

  11. Effects of optimism on motivation in rats

    PubMed Central

    Rygula, Rafal; Golebiowska, Joanna; Kregiel, Jakub; Kubik, Jakub; Popik, Piotr

    2015-01-01

    In humans, optimism is a cognitive construct related to motivation; optimists exert effort, whereas pessimists disengage from effort. In this study, using a recently developed ambiguous-cue interpretation (ACI) paradigm we took the unique opportunity to investigate whether “optimism” as a trait is correlated with motivation in rodents. In a series of ACI tests (cognitive bias screening, CBS), we identified rats displaying “pessimistic” and “optimistic” traits. Subsequently, we investigated the trait differences in the motivation of these rats to gain reward and to avoid punishment using a progressive ratio (PR) schedule of reinforcement paradigm. Although “optimistic” and “pessimistic” animals did not differ in their motivation to avoid punishment, the “optimistic” rats were significantly more motivated to gain reward than their “pessimistic” conspecifics. For the first time, we showed an association between cognitive judgment bias and motivation in an animal model. Because both investigated processes are closely related to mental health and wellbeing, our results may be valuable for preclinical modeling of many psychiatric disorders. PMID:25762910

  12. Anandamide mediates cognitive judgement bias in rats.

    PubMed

    Kregiel, J; Malek, N; Popik, P; Starowicz, K; Rygula, R

    2016-02-01

    In the present study, we investigated the effects of acute pharmacological manipulation of the endocannabinoid (EC) system on the valence of cognitive judgement bias of rats in the ambiguous-cue interpretation (ACI) paradigm. To accomplish this goal, after initial behavioural training, different groups of rats received single, systemic injections of the irreversible anandamide (AEA) hydrolysis inhibitor URB597, the cannabinoid receptor type 1 (CB1) inverse agonist AM251, the cannabinoid receptor type 2 (CB2) inverse agonist AM630, the combination of URB597 and AM251, and a combination of URB597 and AM630 and were subsequently tested with the ACI paradigm. We report that URB597 at a dose of 1 mg/kg significantly biased animals towards positive interpretation of the ambiguous cue and that this effect was abolished by pre-treatment with AM251 (1 mg/kg) or AM630 (1 mg/kg). The CB1 and CB2 inverse agonists administered alone (1 mg/kg) had no statistically significant effects on the interpretation of the ambiguous cue by rats. Our findings suggest involvement of the endocannabinoid system in the mediation of optimistic judgement bias. PMID:26363193

  13. Visual Categorization of Natural Movies by Rats

    PubMed Central

    Vinken, Kasper; Vermaercke, Ben

    2014-01-01

    Visual categorization of complex, natural stimuli has been studied for some time in human and nonhuman primates. Recent interest in the rodent as a model for visual perception, including higher-level functional specialization, leads to the question of how rodents would perform on a categorization task using natural stimuli. To answer this question, rats were trained in a two-alternative forced choice task to discriminate movies containing rats from movies containing other objects and from scrambled movies (ordinate-level categorization). Subsequently, transfer to novel, previously unseen stimuli was tested, followed by a series of control probes. The results show that the animals are capable of acquiring a decision rule by abstracting common features from natural movies to generalize categorization to new stimuli. Control probes demonstrate that they did not use single low-level features, such as motion energy or (local) luminance. Significant generalization was even present with stationary snapshots from untrained movies. The variability within and between training and test stimuli, the complexity of natural movies, and the control experiments and analyses all suggest that a more high-level rule based on more complex stimulus features than local luminance-based cues was used to classify the novel stimuli. In conclusion, natural stimuli can be used to probe ordinate-level categorization in rats. PMID:25100598

  14. Phototoxicity of olaquindox in the rat.

    PubMed

    de Vries, H; Beyersbergen van Henegouwen, G M; Kalloe, F; Berkhuysen, M H

    1990-03-01

    Because of its photoallergic properties quindoxin, a growth promoting feed additive used for example in cattle raising, has been taken off the market. Recently, it appeared that the quindoxin derived olaquindox (OLAQ), used for the same purpose, also produces these light-induced side effects. In this study, phototoxicity of OLAQ was investigated by comparing four groups of rats with a different daily regime: 1 = light plus OLAQ, 2 = dark plus OLAQ, 3 = light (no OLAQ), 4 = dark (no OLAQ). It appeared that rats of group 2 excreted per day approximately 60 per cent of their daily dose as OLAQ and approximately 2 per cent as OLAQ-4-monoxide, whereas these figures were approximately 19 per cent and 30 per cent, respectively, for the light-exposed animals. Besides, rats of group 1 only, suffered from severe erythema, oedema and necrosis of the ears after four days treatment. It is probable that OLAQ, photoactivated in the skin, forms a reactive oxaziridine, analogous to what has been found with the tranquilliser chlordiazepoxide (Librium; Hoffmann La Roche), another imino-N-oxide. PMID:2333431

  15. Trace element distribution in the rat cerebellum

    SciTech Connect

    Kwiatek, W.M.; Long, G.J.; Pounds, J.G.; Reuhl, K.R.; Hanson, A.L.; Jones, K.W.

    1989-10-01

    Spatial distributions and concentrations of trace elements (TE) in the brain are important because TE perform catalytic structural functions in enzymes which regulate brain function and development. We have investigated the distributions of TE in rat cerebellum. Structures were sectioned and analyzed by the Synchrotron Radiation Induced X-ray Emission (SRIXE) method using the NSLS X-26 white-light microprobe facility. Advantages important for TE analysis of biological specimens with x-ray microscopy include short time of measurement, high brightness and flux, good spatial resolution, multielemental detection, good sensitivity, and non-destructive irradiation. Trace elements were measured in thin rat brain sections of 20-micrometers thickness. The analyses were performed on sample volumes as small as 0.2 nl with Minimum Detectable Limits (MDL) of 50 ppb wet weight for Fe, 100 ppb wet weight for Cu, and Zn, and 1 ppM wet weight for Pb. The distribution of TE in the molecular cell layer, granule cell layer and fiber tract of rat cerebella was investigated. Both point analyses and two-dimensional semi-quantitative mapping of the TE distribution in a section were used.

  16. Plasminogen receptors on rat colon carcinoma cells.

    PubMed Central

    Durliat, M.; Komano, O.; Correc, P.; Bertrand, O.; Cochet, S.; Caignard, A.; Martin, F.; Burtin, P.

    1992-01-01

    Cells from rat carcinoma cell lines PROb (giving progressive tumours) and REGb (giving regressive tumours) have cell surface receptors which bind specifically rat plasminogen and plasmin. Affinity for Pg was found to be higher in PROb (Kd = 10(-7) M) than in REGb cells (Kd = 5.10(-7) M) but with a concomitant decrease in the number of binding sites, 0.9 x 10(6)/cell (range from 0.6 to 1.2 x 10(6)) in PROb vs 3.6 x 10(6)/cell (range 1.2 to 6 x 10(6)) in REGb cells. The number and the affinity of binding sites varied in an opposite way in PROb and REGb cells. The difference in affinity parameters was unrelated to the degree of invasiveness of tumour cells in syngenetic rats. Bound plasmin retained its enzymatic activity, which indicates that its binding does not involve the catalytic active site. In cell solubilisates plasminogen receptor appeared as one major band situated in the area of 50-60 kDa. Images Figure 3 Figure 5 PMID:1322156

  17. Curt Richter and the female rat.

    PubMed

    Geary, Nori

    2007-09-01

    Richter fully appreciated the fundamental biological importance of sex differences, in particular the challenges of female reproductive function to the two classes of behavior that most engaged him, endogenous rhythms and "self-regulatory" behaviors. Indeed, his contributions in these areas justify honoring him as one of the founders of behavioral neuroendocrinology. During the 1920s Richter, together with Wang, Kinder and other students, performed elegant phenomenological and mechanistic studies of sex differences in rats' spontaneous locomotor activity, nest building, and food intake. All of these behaviors display rhythms entrained to the ovarian cycle in female rats, and Richter's analyses of them formed the bases of many current areas of behavioral neuroscience. Slightly later, Richter made fundamentally important discoveries related to nutrient self-selection in pregnant and lactating rats, including changes in micronutrient and macronutrient selection. These data played a major role in the development of his concept of behavioral regulation of homeostasis. Unfortunately, some of these discoveries are rarely recalled. This is both historically regrettable and potentially an impediment to contemporary research progress. PMID:17544544

  18. Binding of episodic memories in the rat

    PubMed Central

    Crystal, Jonathon D.; Smith, Alexandra E.

    2014-01-01

    Summary People remember an event as a coherent scene [1-4]. Memory of such an episode is thought to reflect binding of a fully integrated representation, rather than memory of unconnected features [4-7]. However, it is not known if rodents form bound representations. Here we show that rats remember episodes as bound representations. Rats were presented with multiple features of unique episodes at memory encoding: what (food flavor), where (maze location), source (self-generated food seeking–running to the food site– or experimenter-generated food seeking –placement by the experimenter at the food site), and context (spatial cues in the room where the event occurred). After a delay, the trial continued with a memory assessment in which one flavor replenished at the self-generated- but not at experimenter-generated-locations. We presented rats with multiple overlapping features, in rapid succession, to ensure that successful memory retrieval required them to disambiguate multiple study episodes (using two rooms). We found that binding is resistant to interference from highly similar episodes and survives long retention intervals (~1 week). Our results suggest that multiple episodic memories are each structured as bound representations, which suggests that nonhumans represent episodic memories using a structure similar to that of people. This finding enhances the translational potential for utilizing animal models of episodic memory to explore the biological mechanisms of memory and validate therapeutic approaches for treating disorders of memory. PMID:25466681

  19. Different transfer of nociceptive sensitivity from rats with postnatal hippocampal lesions to control rats.

    PubMed

    Yamamotová, Anna; Franek, Miloslav; Vaculín, Simon; St'astný, Frantisek; Bubeníková-Valesová, Vera; Rokyta, Richard

    2007-07-01

    Hippocampal lesions in newborn rats alter the development of mechanisms involved in the processing of nociception. The hippocampal lesion was induced by the bilateral infusion, into the lateral cerebral ventricles, of 0.25 microL of saline containing either 0.25 micromol quinolinic acid (QUIN) and/or 0.25 micromol N-acetyl-L-aspartyl-L-glutamate (NAAG) on postnatal day 12. The same amount of sterile saline was injected into the sham-operated animals (group SHAM). It was expected that the QUIN- and NAAG-lesioned rats would exhibit some differences in thermal pain perception; however, we wanted to know if the control rats would exhibit, at least in part, similar changes in pain perception as their chemically lesioned siblings with which they were housed. Young adult NAAG-injured rats exhibited increased withdrawal latencies in the tail-flick and plantar tests, whereas young adult QUIN-injured animals exhibited only marginally decreased latencies. Nociceptive responses in the SHAM rats paralleled the littermates that had been neonatally treated with QUIN or NAAG, i.e. the responses in the SHAM(QUIN) group decreased, whereas the responses in the SHAM(NAAG) group increased. No significant changes in nociception were observed in intact animals, regardless of which group they were housed with. Our results show that social factors, which were originally demonstrated only for the pain behavior, may also influence basal nociceptive sensitivity in rats. We concluded that the "sham operation" may have had a long-term, nonspecific impact on nociceptive behavior by inducing behavioral mimicry of other animals. PMID:17623020

  20. Rickettsial pathogens in the tropical rat mite Ornithonyssus bacoti (Acari: Macronyssidae) from Egyptian rats (Rattus spp.).

    PubMed

    Reeves, Will K; Loftis, Amanda D; Szumlas, Daniel E; Abbassy, Magda M; Helmy, Ibrahim M; Hanafi, Hanafi A; Dasch, Gregory A

    2007-01-01

    We collected and tested 616 tropical rat mites (Ornithonyssus bacoti (Hirst)) from rats (Rattus norvegicus (Berkenhout) and R. rattus (Linnaeus)) throughout 14 governorates in Egypt and tested DNA extracts from pools of these mites for Bartonella spp., Coxiella burnetii, and Rickettsia spp. by PCR amplification and sequencing. Three different mite-associated bacterial agents, including one Bartonella and two Rickettsia spp., were detected in eight pools of mites. Further research could demonstrate the vector potential of mites and pathogenicity of these agents to humans or animals. PMID:17225079

  1. Mortality associated with using medetomidine and ketamine for general anesthesia in pregnant and nonpregnant Wistar rats.

    PubMed

    Callahan, Lauren M; Ross, Simone M; Jones, Megan L; Musk, Gabrielle C

    2014-06-01

    Medetomidine and ketamine are injectable drugs that can be used in combination to induce general anesthesia in rats. After noticing a high incidence of morbidity and mortality in pregnant Wistar rats given medetomidine and ketamine for anesthesia, the authors further investigated the effects of this combination of anesthetic drugs in both pregnant and nonpregnant Wistar rats. The time to recumbency and the duration of general anesthesia were similar between pregnant and nonpregnant rats. Pregnancy status did not affect the rats' pulse rate, respiratory rate, rectal temperature, oxygen saturation or perfusion index during 2 h of anesthesia. Pregnant rats had significantly lower blood glucose concentrations than nonpregnant rats at all time points, though blood glucose concentrations increased in both groups. The mortality rate was ∼15% both for nonpregnant rats and for pregnant rats. Researchers using medetomidine and ketamine to anesthetize Wistar rats should carefully monitor the rats in order to minimize mortality. PMID:24845007

  2. Raloxifene prevents endothelial dysfunction in aging ovariectomized female rats.

    PubMed

    Wong, Chi Ming; Yao, Xiaoqiang; Au, Chak Leung; Tsang, Suk Ying; Fung, Kwok Pui; Laher, Ismail; Vanhoutte, Paul M; Huang, Yu

    2006-05-01

    Lack of an appropriate animal model has delayed the better understanding of mechanisms related to higher cardiovascular risk in women after menopause. The aging female rat may share some menopausal changes observed in women. However, most studies have attempted to mimic menopause by ovariectomizing young (6-12 weeks old) animals without taking into accounts the influence of aging and of declining ovarian function. Therefore, the present study examined changes in vascular reactivity in the aging (15 months old) female rat after ovariectomy and the effects of chronic raloxifene therapy on vascular reactivity and eNOS protein expression. Aortic rings were prepared from the three experimental groups of rats: sham-operated control, ovariectomized and ovariectomized aging rats receiving daily oral administration of raloxifene for 3 months. Aortic rings were suspended in organ baths for the measurement of isometric tension. Rings with endothelium contracted significantly more to phenylephrine after inhibition of nitric oxide/cyclic GMP-signaling pathway by L-NAME or ODQ (as an index of basal nitric oxide release) in control and raloxifene-treated ovariectomized rats than in ovariectomized rats. This effect was abolished upon mechanical removal of the endothelium. Phenylephrine induced greater contractions only in rings with endothelium from ovariectomized rats as compared with control rats and raloxifene treatment normalized this response. In the presence of L-NAME or ODQ, phenylephrine-induced contraction was similar in rings from the three groups. Rings relaxed more to thapsigargin and acetylcholine in raloxifene-treated ovariectomized rats than in ovariectomized rats. There was no significant difference in aortic eNOS protein contents among the different groups. These results suggest that chronic oral administration of raloxifene to aging ovariectomized female rats augmented the bioavailability of endothelial nitric oxide in isolated aortic rings without altering e

  3. Amphetamine modifies ethanol intake of psychosocially stressed male rats.

    PubMed

    Pohorecky, Larissa A; Sweeny, April

    2012-05-01

    Studies of socially housed rodents have provided significant information regarding the consequences of exposure to stressors. Psychosocial stressors are known to alter the ingestion of ethanol and the activity of the dopaminergic neuronal system. Since both stressors and ethanol are known to affect the function of dopaminergic neurons, we employed amphetamine to assess the role of this neural system on the ingestion of ethanol by psychosocially stressed male rats. Male rats housed two per cage were designated as dominant or subdominant rats based on evaluations of agonistic behavior and body weight changes. The dyad-housed rats and a group of single-housed rats were sequentially assessed for ethanol intake after injections of saline or amphetamine (0.3, 0.9 or 2.7 mg/kg i.p.) both prior to dyad housing and subsequently again during dyad-housing. Prior to dyad housing ethanol intake of future subdominant rats was higher than that of future dominant rats. Dyad-housing significantly increased ethanol intake of dominant rats. Pre-dyad the highest dose of amphetamine potently depressed ethanol ingestion. Sensitivity to amphetamine's depressant effect on ethanol intake was higher at the dyad test in all subjects, most prominently in single-housed rats. In contrast to the single-housed rats, the dyad-housed rats displayed saccharin anhedonia. It can be concluded that dopaminergic system modulates, at least partially, the psychosocial stress-induced changes in ethanol intake. Furthermore, the level of ethanol ingestion at the pre-dyad test was predictive of future hierarchical status. PMID:22285324

  4. Intrasplenic transplantation of allogeneic hepatocytes prolongs survival in anhepatic rats.

    PubMed

    Arkadopoulos, N; Lilja, H; Suh, K S; Demetriou, A A; Rozga, J

    1998-11-01

    To examine whether hepatocytes transplanted in the spleen can function as an ectopic liver, we performed hepatocyte transplantation in rats that were rendered anhepatic. Total hepatectomy was performed by using a novel single-stage technique. Following hepatectomy, Group 1 rats (n = 16) were monitored until death to determine survival time without prior intervention. Group 2 anhepatic rats (n = 20) were sacrificed at various times to measure blood hepatocyte growth factor (HGF) and transforming growth factor beta1 (TGF-beta1) levels. Group 3 (n = 16) rats received intrasplenic injection of isolated hepatocytes (2.5 x 10(7) cells/rat) followed by total hepatectomy after 3 days. Group 4 (n = 12) sham-transplanted rats received intrasplenic saline infusion, and after 3 days they were rendered anhepatic. Group 2, 3, and 4 rats were maintained on daily Cyclosporine A (10 mg/kg; intramuscularly). Group 1 anhepatic rats survived for 22.4 +/- 5.2 hours (standard deviation). The anhepatic state was associated with a progressive and statistically significant rise in blood HGF and TGF-beta1 levels. Rats that received hepatocyte transplantation before total hepatectomy had a significantly longer survival time than sham-transplanted anhepatic controls (34.1 +/- 8.5 vs. 15.5 +/- 4.8 hrs, P < .01). Additionally, at 12 hours post-hepatectomy, transplanted rats had significantly lower blood ammonia, prothrombin time, international normalized ratio, and TGF-beta1 levels when compared with sham-transplanted controls. In conclusion, intrasplenic transplantation of allogeneic hepatocytes prolonged survival, improved blood chemistry, and lowered blood TGF-beta1 levels in rats rendered anhepatic. PMID:9794923

  5. The effect of dietary pyridoxine on arsenic deprivation in rats

    SciTech Connect

    Uthus, E.O.; Poelllot, R. )

    1991-03-15

    In experiments on As deprivation, many findings indicate that As can affect enzymes or metabolites that are also influenced by vitamin B{sub 6}. Thus, an experiment was designed to ascertain the effect of pyridoxine (pyr) on As deprivation in rats. Male, weanling rats were fed an amino acid based diet containing 0.24% methionine (M) and less than 15 ng As/g. Dietary variables were As, 0 or 1 {mu}g/g; M, 0 or 3 g/kg; and pyridoxine, 0 or 10 mg/kg. After 10 weeks, growth was reduced by As, Pyr, or M deprivation. Both endogenous ({minus}PP) and pyridoxal phosphate-stimulated (+PP) RBC aspartate aminotransferase were decreased by Pyr deficiency. The ratio of +PP/{minus}PP, known as the activation coefficient (AC), was affected by an interaction between As and Pyr. Pyr deficiency resulted in a less marked increase in AC in the As-deprived rats than in the As-supplemented rats. Plasma Fe was slightly decreased by Pyr deficiency in the As-deprived rats but increased by Pyr deficiency in the As-supplemented rats. Plasma threonine and serine were increased by As supplementation in the Pyr-deficient rats but there was no effect of As supplementation in the Pyr-supplemented rats. Plasma alanine was decreased by As or Pyr deprivation. In Pyr deficiency, As deprivation had no effect on plasma glycine (G) in the M-deficient rats but decreased G in the M-supplemented rats. In the Pyr-supplemented rats, As had no effect on G, regardless of M. The findings indicate that As and Pyr interact to affect amino acid metabolism.

  6. Isoproterenol effects evaluated in heart slices of human and rat in comparison to rat heart in vivo

    SciTech Connect

    Herrmann, Julia E.; Heale, Jason; Bieraugel, Mike; Ramos, Meg; Fisher, Robyn L.; Vickers, Alison E.M.

    2014-01-15

    Human response to isoproterenol induced cardiac injury was evaluated by gene and protein pathway changes in human heart slices, and compared to rat heart slices and rat heart in vivo. Isoproterenol (10 and 100 μM) altered human and rat heart slice markers of oxidative stress (ATP and GSH) at 24 h. In this in vivo rat study (0.5 mg/kg), serum troponin concentrations increased with lesion severity, minimal to mild necrosis at 24 and 48 h. In the rat and the human heart, isoproterenol altered pathways for apoptosis/necrosis, stress/energy, inflammation, and remodeling/fibrosis. The rat and human heart slices were in an apoptotic phase, while the in vivo rat heart exhibited necrosis histologically and further progression of tissue remodeling. In human heart slices genes for several heat shock 70 kD members were altered, indicative of stress to mitigate apoptosis. The stress response included alterations in energy utilization, fatty acid processing, and the up-regulation of inducible nitric oxide synthase, a marker of increased oxidative stress in both species. Inflammation markers linked with remodeling included IL-1α, Il-1β, IL-6 and TNFα in both species. Tissue remodeling changes in both species included increases in the TIMP proteins, inhibitors of matrix degradation, the gene/protein of IL-4 linked with cardiac fibrosis, and the gene Ccl7 a chemokine that induces collagen synthesis, and Reg3b a growth factor for cardiac repair. This study demonstrates that the initial human heart slice response to isoproterenol cardiac injury results in apoptosis, stress/energy status, inflammation and tissue remodeling at concentrations similar to that in rat heart slices. - Highlights: • Human response to isoproterenol induced cardiac injury evaluated in heart slices. • Isoproterenol altered apoptosis, energy, inflammation and remodeling pathways. • Human model verified by comparison to rat heart slices and rat heart in vivo. • Human and rat respond to isoproterenol

  7. DIETARY SUBACUTE TOXICITY OF ETHYLENEBISISOTHIOCYANATE SULFIDE IN THE LABORATORY RAT

    EPA Science Inventory

    Ethylenebisisothiocyanate sulfide (EBIS) was fed to groups of rats at 0, 1, 10, 100, and 1000 ppm for up to 90 days. Only those rats receiving EBIS at 1000 ppm demonstrated a toxic response to the test chemical reflected as a reversible paralysis of the hind legs noted within 8 t...

  8. The Special Status of Actions in Causal Reasoning in Rats

    ERIC Educational Resources Information Center

    Leising, Kenneth J.; Wong, Jared; Waldmann, Michael R.; Blaisdell, Aaron P.

    2008-01-01

    A. P. Blaisdell, K. Sawa, K. J. Leising, and M. R. Waldmann (2006) reported evidence for causal reasoning in rats. After learning through Pavlovian observation that Event A (a light) was a common cause of Events X (an auditory stimulus) and F (food), rats predicted F in the test phase when they observed Event X as a cue but not when they generated…

  9. PSUEDOPREGNANCY AND THE DECIDUAL CELL RESPONSE IN THE RAT

    EPA Science Inventory

    Pseudopregnancy, an induced physiological state in the rat which mimics the rodent's luteal phase, can be used to assess the impact of chemicals on the luteal phase of female animals. emale rats can be induced to be pseudopregnant by a variety of methods and assessment of the suc...

  10. EFFECTS OF TRICHLOROETHYLENE EXPOSURE ON MALE REPRODUCTIVE FUNCTION IN RATS

    EPA Science Inventory

    The present study was designed to evaluate the influences of trichloroethylene (TCE) on the reproductive system of male rats. In addition, information was obtained on the distribution and metabolism of TCE. At 100 days of age, male rats were allowed to copulate with ovariectomize...

  11. Dietary modulation of oral amphetamine intake in rats.

    PubMed

    Kanarek, R B; Marks-Kaufman, R

    1988-01-01

    The interaction of sucrose availability and oral self-administration of amphetamine was examined in 23 male Sprague-Dawley rats. Fourteen rats were given a 0.075 mg/ml amphetamine sulfate solution as their sole source of fluid and 9 rats were given water. Feeding conditions were alternated between weeks with both granulated sucrose and chow available and weeks with only chow present. Rats drank significantly less of the amphetamine solution when consuming sucrose and chow than when eating chow alone. Sucrose intake had a slight effect on water intake. Rats drinking the amphetamine solution consumed significantly less food, gained significantly less weight, and were significantly less efficient at using calories for weight gain than rats drinking water. However, when given access to sucrose, rats drinking the amphetamine solution chose a significantly greater proportion of their daily caloric intake as sucrose (60%) than rats drinking water (42.5%). The present results demonstrate that 1) amphetamine intake alters nutrient choice and 2) that dietary variables can profoundly affect drug self-administration. PMID:3237840

  12. Rats Depend on Habit Memory for Discrimination Learning and Retention

    ERIC Educational Resources Information Center

    Broadbent, Nicola J.; Squire, Larry R.; Clark, Robert E.

    2007-01-01

    We explored the circumstances in which rats engage either declarative memory (and the hippocampus) or habit memory (and the dorsal striatum). Rats with damage to the hippocampus or dorsal striatum were given three different two-choice discrimination tasks (odor, object, and pattern). These tasks differed in the number of trials required for…

  13. Intelligence-Augmented Rat Cyborgs in Maze Solving

    PubMed Central

    Yu, Yipeng; Pan, Gang; Gong, Yongyue; Xu, Kedi; Zheng, Nenggan; Hua, Weidong; Zheng, Xiaoxiang; Wu, Zhaohui

    2016-01-01

    Cyborg intelligence is an emerging kind of intelligence paradigm. It aims to deeply integrate machine intelligence with biological intelligence by connecting machines and living beings via neural interfaces, enhancing strength by combining the biological cognition capability with the machine computational capability. Cyborg intelligence is considered to be a new way to augment living beings with machine intelligence. In this paper, we build rat cyborgs to demonstrate how they can expedite the maze escape task with integration of machine intelligence. We compare the performance of maze solving by computer, by individual rats, and by computer-aided rats (i.e. rat cyborgs). They were asked to find their way from a constant entrance to a constant exit in fourteen diverse mazes. Performance of maze solving was measured by steps, coverage rates, and time spent. The experimental results with six rats and their intelligence-augmented rat cyborgs show that rat cyborgs have the best performance in escaping from mazes. These results provide a proof-of-principle demonstration for cyborg intelligence. In addition, our novel cyborg intelligent system (rat cyborg) has great potential in various applications, such as search and rescue in complex terrains. PMID:26859299

  14. CARBONYL SULFIDE INHALATION PRODUCES BRAIN LESIONS IN F344 RATS.

    EPA Science Inventory

    Carbonyl sulfide (COS) is an intermediate in the production of pesticides and herbicides, and is a metabolite of the neurotoxicant carbon disulfide. The potential neurotoxicity of inhaled COS was investigated in F344 rats. Male rats were exposed to 0, 75, 150, 300, or 600 ppm COS...

  15. Silent or Vocalizing Rats Copulate in a Similar Manner

    PubMed Central

    Ågmo, Anders; Snoeren, Eelke M. S.

    2015-01-01

    Both male and female rats produce 50 kHz ultrasonic vocalizations (USVs) in the presence of a sexual partner and during copulation. Previous studies showed that USVs have no incentive value for rats. In this study, we evaluated the role of USVs in behavior during copulation. Three groups of rats were used: sham males paired with sham females, devocalized females paired with sham males, and sham females paired with devocalized males. During the copulation test, the USVs emitted by the sham rat were recorded and the sexual behavior of both the male and the female were observed. The results revealed that devocalized and sham females showed similar patterns of sexual behavior and no difference was found in the copulatory behavior of devocalized and sham males. Also the behavior of the partner of a sham rat was comparable to the partner of a devocalized rat. In addition, almost no changes in USVs emission were found in the 5 seconds before and/or after a copulatory behavior. It can be concluded that USVs play no important role in rat copulatory behavior at least in sexually naïve rats. PMID:26633013

  16. Factors modulating social influence on spatial choice in rats.

    PubMed

    Bisbing, Teagan A; Saxon, Marie; Sayde, Justin M; Brown, Michael F

    2015-07-01

    Three experiments examined the conditions under which the spatial choices of rats searching for food are influenced by the choices made by other rats. Model rats learned a consistent set of baited locations in a 5 × 5 matrix of locations, some of which contained food. In Experiment 1, subject rats could determine the baited locations after choosing 1 location because all of the baited locations were on the same side of the matrix during each trial (the baited side varied over trials). Under these conditions, the social cues provided by the model rats had little or no effect on the choices made by the subject rats. The lack of social influence on choices occurred despite a simultaneous social influence on rats' location in the testing arena (Experiment 2). When the outcome of the subject rats' own choices provided no information about the positions of other baited locations, on the other hand, social cues strongly controlled spatial choices (Experiment 3). These results indicate that social information about the location of food influences spatial choices only when those cues provide valid information that is not redundant with the information provided by other cues. This suggests that social information is learned about, processed, and controls behavior via the same mechanisms as other kinds of stimuli. PMID:26010213

  17. Geographic Range Expansion for Rat Lungworm in North America

    PubMed Central

    Creecy, James P.; Lord, Wayne D.; Caire, William

    2015-01-01

    Using quantitative PCR analysis and DNA sequencing, we provide evidence for the presence of rat lungworm (Angiostrongylus cantonensis) in Oklahoma, USA, and identified a potentially novel rat host (Sigmodon hispidus). Our results indicate a geographic range expansion for this medically and ecologically relevant parasite in North America. PMID:26079818

  18. Cardiac and thermal homeostasis in the aging Brown Norway rat.

    EPA Science Inventory

    The Brown Norway (BN) rat is a popular strain for aging studies. There is little information on effects of age on baseline cardiac and thermoregulatory parameters in undisturbed BN rats even though cardiac and thermal homeostasis is linked to many pathological deficits in the age...

  19. Low blood alcohol levels in rats despite chronic alcohol consumption

    SciTech Connect

    Sankaran, H.; Deveney, C.W.; Lin, J.C.; Larkin, E.C.; Rao, G.A. )

    1989-02-09

    Rats fed liquid diets containing 36% or 26% of calories from ethanol consume similar amounts of alcohol each day. After 3 weeks on ethanol diet, the blood alcohol levels (BAL) are high in rats fed the 36% alcohol diet, but low or insignificant in those fed the 26% alcohol diet. Rats in either alcohol diet group consume most of their diet in the night. Hence, the low BAL in 26% ethanol diet-fed rats may not be due to a more rapid diet consumption after feeding and clearance of the bulk of ingested alcohol as compared to the rats fed the 36% alcohol diet. BAL at various times during the day (7 AM, 10 AM, 1 PM, 4 PM, 7 PM and 10 PM) are high in rats fed the 36% ethanol diet. However, BAL in those fed the 26% ethanol diet are low during the corresponding times. It appears that the low BAL produced by the enhanced hepatic metabolism of ethanol is related to the improved nutritional status in rats fed the 26% ethanol diet, compared to those fed 36% ethanol diet, because rats fed the 36% ethanol diet ingest reduced amounts of calories and other nutrients. Extrahepatic effects of chronic alcohol consumption caused by high BAL may be abated by an enhanced daily intake of nutrients by the animal.

  20. Delay Discounting of Qualitatively Different Reinforcers in Rats

    ERIC Educational Resources Information Center

    Calvert, Amanda L.; Green, Leonard; Myerson, Joel

    2010-01-01

    Humans discount larger delayed rewards less steeply than smaller rewards, whereas no such magnitude effect has been observed in rats (and pigeons). It remains possible that rats' discounting is sensitive to differences in the quality of the delayed reinforcer even though it is not sensitive to amount. To evaluate this possibility, Experiment 1…

  1. Breed differences in clearance of porcine FSH in hypophysectomized rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extracts of anterior pituitary (AP) glands were infused iv into hypophysectomized male rats followed by sequential sampling of blood for 120 min. Determination of follicle-stimulating hormone (FSH) concentrations established that FSH from Chinese Meishan males decreased in the circulation of rats mo...

  2. PHARMACOLOGIC PROBING OF RENAL DEVELOPMENT IN THE NEONATAL RAT

    EPA Science Inventory

    The study was designed to examine the ontogeny of renal functions in the neonatal rat using various pharmacologic agents as probes. The renal responses of 2, 6, and 10 day old rats to diuretic agents known to act on proximal tubules, loops of Henle and distal tubules were assesse...

  3. Alcoholic Steatosis in Different Strains of Rat: A Comparative Study

    PubMed Central

    Bhopale, Kamlesh K.; Kondraganti, Shakuntala; Fernando, Harshica; Boor, Paul J.; Kaphalia, Bhupendra S.; Shakeel Ansari, G. A.

    2016-01-01

    Background Different strains of rats have been used to study alcoholic liver disease (ALD) while the reason for selecting a particular rat strain was not apparent. Purpose The aim of our study was to compare outbred (Wistar) and inbred (Fischer) strains to evaluate pathological, biochemical changes, and gene expression differences associated with ethanol-induced early hepatic steatosis. Study Design Male Wistar and Fischer-344 rats were pair-fed for 6 weeks with or without 5% ethanol in Lieber-DeCarli liquid diet. Livers were analyzed for histological and lipid-related differences. Results Hepatic midzonal steatosis was mainly found in Wistar rats while Fischer rats showed mostly pericentral steatosis. Increased hepatic steatosis in ethanol-fed Wistar rats is supported by increases in lipids with related genes and transcription factors involved in fatty acid and triglyceride synthesis. Conclusion Our data showed that Fischer rats are relatively less prone to ethanol-mediated steatosis with pericentral lipid deposition pattern in the liver which is similar to humans and show no trace level of lipid accumulation in pair-fed controls as observed in Wistar (outbred) strain. Therefore, Fischer rats are better suited for lipid studies in an early development of ALD. PMID:27213081

  4. ATRAZINE EFFECTS ON EARLY PREGNANCY AND IMPLANATION IN THE RAT

    EPA Science Inventory

    Atrazine Effects on Early Pregnancy and Implantation in the Rat.
    A.M. Cummings, B.E. Rhodes*, and R.L. Cooper*.
    Reproductive Toxicology Division, NHEERL, USEPA, Research Triangle Park, NC
    Atrazine (ATR), an herbicide, can induce mammary tumors in rats. ATR can also sup...

  5. EFFECTS OF ACROLEIN ON MACROPHAGE FUNCTIONS IN RATS

    EPA Science Inventory

    Male Sprague-Dawley rats were exposed to 0.1, 1.0, or 3.0 ppm acrolein or filtered air 6 h/day, 5 days/week for 3 weeks. Rats were tested one day following the last exposure and exhibited no change in pulmonary clearance of inhaled (35)S-labeled Klebsiella pneumoniae at any acrol...

  6. Fix and Sample with Rats in the Dynamics of Choice

    ERIC Educational Resources Information Center

    Aparicio, Carlos F.; Baum, William M.

    2006-01-01

    The generality of the molar view of behavior was extended to the study of choice with rats, showing the usefulness of studying order at various levels of extendedness. Rats' presses on two levers produced food according to concurrent variable-interval variable-interval schedules. Seven different reinforcer ratios were arranged within each session,…

  7. Social buffering ameliorates conditioned fear responses in female rats.

    PubMed

    Ishii, Akiko; Kiyokawa, Yasushi; Takeuchi, Yukari; Mori, Yuji

    2016-05-01

    The stress experienced by an animal is ameliorated when the animal is exposed to distressing stimuli along with a conspecific animal(s). This is known as social buffering. Previously, we found that the presence of an unfamiliar male rat induced social buffering and ameliorated conditioned fear responses of a male rat subjected to an auditory conditioned stimulus (CS). However, because our knowledge of social buffering is highly biased towards findings in male subjects, analyses using female subjects are crucial for comprehensively understanding the social buffering phenomenon. In the present studies, we assessed social buffering of conditioned fear responses in female rats. We found that the estrus cycle did not affect the intensity of the rats' fear responses to the CS or their degree of vigilance due to the presence of a conspecific animal. Based on these findings, we then assessed whether social buffering ameliorated conditioned fear responses in female rats without taking into account their estrus cycles. When fear conditioned female rats were exposed to the CS without the presence of a conspecific, they exhibited behavioral responses, including freezing, and elevated corticosterone levels. By contrast, the presence of an unfamiliar female rat suppressed these responses. Based on these findings, we conclude that social buffering can ameliorate conditioned fear responses in female rats. PMID:27060333

  8. IN VITRO COMPARISON OF RAT AND CHICKEN BRAIN NEUROTOXIC ESTERASE

    EPA Science Inventory

    A systematic comparison was undertaken to characterize neurotoxic esterase (NTE) from rat and chicken brain in terms of inhibitor sensitivities, pH optima, and molecular weights. Paraoxon titration of phenyl valerate (PV)-hydrolyzing carboxylesterased showed that rat esterases we...

  9. FUNCTIONAL TERATOGENS OF THE RAT KIDNEY II. NITROFEN AND ETHYLENETHIOUREA

    EPA Science Inventory

    Nitrofen and ethylenethiourea (ETU), agents known to prenatally induce hydronephrosis in rats, were assessed for their effects on postnatal renal functional maturation. oth were given by gavage to pregnant Sprague-Dawley rats on Gestation Day 11. itrofen was given at concentratio...

  10. Using Giant African Pouched Rats ("Cricetomys Gambianus") to Detect Landmines

    ERIC Educational Resources Information Center

    Poling, Alan; Weetjens, Bart J.; Cox, Christophe; Beyene, Negussie W.; Sully, Andrew

    2010-01-01

    Within the past decade, giant pouched rats have been used successfully to detect landmines. This manuscript summarizes how these rats are trained and used operationally. The information provided is intended to be of practical value toward strengthening best practices in using "Cricetomys" for humanitarian purposes while simultaneously ensuring the…

  11. The Effects of Reinforcer Magnitude on Timing in Rats

    ERIC Educational Resources Information Center

    Ludvig, Elliot A.; Conover, Kent; Shizgal, Peter

    2007-01-01

    The relation between reinforcer magnitude and timing behavior was studied using a peak procedure. Four rats received multiple consecutive sessions with both low and high levels of brain stimulation reward (BSR). Rats paused longer and had later start times during sessions when their responses were reinforced with low-magnitude BSR. When estimated…

  12. Standardization of resistance exercise training: effects in diabetic ovariectomized rats.

    PubMed

    Sanches, I C; Conti, F F; Sartori, M; Irigoyen, M C; De Angelis, K

    2014-04-01

    This study was carried out with a 3-fold aim: 1) to standardize a maximal load test (MLT) on ladders for prescription of resistance exercise training (RET) in rats, 2) to prescribe moderate-intensity RET based on this MLT and 3) to test the effect of this RET in diabetic ovariectomized rats. Female Wistar rats were divided into control (C), diabetic ovariectomized sedentary (DOS) and trained (DOT) groups. The MLT was standardized with increased load applied to the rat tail for each climb, and blood lactate was measured to identify lactate threshold in C rats. MLT was applied in the 1st, 4th and 8th week of the protocol. After 8 weeks of RET, the arterial pressure was directly recorded. DOS group reduced performance in MLT, body weight, left ventricular, plantar and soleus muscles mass (vs. C). DOT rats showed an improvement in MLT associated with plantar muscle mass increased (vs. C and DOS), with attenuation of hypotension and bradycardia (vs. DOS). In conclusion, the results provide a useful method for determining the maximal load and applying RET in rats. Moreover, this study showed that moderate intensity RET improves hemodynamic status in diabetic ovariectomized rats, thereby reinforcing the role of RET in diabetes management. PMID:24022577

  13. Preparation of Rat Serum Suitable for Mammalian Whole Embryo Culture

    PubMed Central

    Takahashi, Masanori; Makino, Sayaka; Kikkawa, Takako; Osumi, Noriko

    2014-01-01

    Mammalian whole embryo culture (WEC) is a widely used technique for examining pharmacological toxicity in developing mouse and rat embryos and for investigating the mechanisms of developmental processes. Immediately centrifuged (IC) rat serum is commonly used for WEC and is essential for the growth and development of cultured mouse and rat embryos ex vivo. For the culture of midgestation embryos (i.e., E8.0-12.5 for the mouse, and E10.0-14.5 for the rat), 100% rat serum is the best media for supporting the growth of the embryo ex vivo. To prepare rat serum suitable for WEC, the collected blood should be centrifuged immediately to separate the blood cells from the plasma fraction. After centrifugation, the fibrin clot forms in the upper layer; this clot should be squeezed gently using a pair of sterile forceps and subsequently centrifuged to completely separate the blood cells from the serum. In this video article, we demonstrate our standard protocol for the preparation of optimal IC rat serum, including blood collection from the abdominal aorta of male rats and extraction of the serum by centrifugation. PMID:25145996

  14. TRIETHYLTIN-INDUCED NEURONAL DAMAGE IN NEONATALLY EXPOSE RATS

    EPA Science Inventory

    Neuropathological and biochemical effects of neonatal exposure to the alkyl metal triethyltin were examined in Long Evans juvenile male rats. Rats were injected intraperitoneally on post-natal day 5 with 6 mk/kg of triethyltin bromide and sampled on day 20. The brains of tin-trea...

  15. Biochemical and histochemical adaptations of skeletal muscle to rat suspension

    NASA Technical Reports Server (NTRS)

    Templeton, G. H.

    1984-01-01

    The influence of rat suspension on soleus disuse and atrophy was investigated to measure changes in fiber area and number and to determine if suspension elicited changes in lysosomal protease activity and rate of calcium uptake by the sarcoplasmic reticulum. The infuence of rat suspension on myosin light chain phosphorylation and succinate dehydrogenase activity are determined.

  16. ACUTE BEHAVIORAL TOXICITY OF CARBARYL AND PROPOXUR IN ADULT RATS

    EPA Science Inventory

    Motor activity and neuromotor function were examined in adult CD rats exposed to either carbaryl or propoxur, and behavioral effects were compared with the time course of cholinesterase inhibition. Rats received an IP injection of either 0, 2, 4, 6 or 8 mg/kg propoxur or 0, 4, 8,...

  17. LIVER REGENERATION STUDIES WITH RAT HEPATOCYTES IN PRIMARY CULTURE

    EPA Science Inventory

    Adult rat parenchymal hepatocytes in primary culture can be induced to enter into DNA synthesis and mitosis. The optimal conditions for hepatocyte replication are low plating density (less than 10,000 cells/sq cm) and 50% serum from two-thirds partially hepatectomized rats (48 hr...

  18. The Laboratory Rat: Relating Its Age With Human's

    PubMed Central

    Sengupta, Pallav

    2013-01-01

    By late 18th or early 19th century, albino rats became the most commonly used experimental animals in numerous biomedical researches, as they have been recognized as the preeminent model mammalian system. But, the precise correlation between age of laboratory rats and human is still a subject of debate. A number of studies have tried to detect these correlations in various ways, But, have not successfully provided any proper association. Thus, the current review attempts to compare rat and human age at different phases of their life. The overall findings indicate that rats grow rapidly during their childhood and become sexually mature at about the sixth week, but attain social maturity 5-6 months later. In adulthood, every day of the animal is approximately equivalent to 34.8 human days (i.e., one rat month is comparable to three human years). Numerous researchers performed experimental investigations in albino rats and estimated, in general, while considering their entire life span, that a human month resembles every-day life of a laboratory rat. These differences signify the variations in their anatomy, physiology and developmental processes, which must be taken into consideration while analyzing the results or selecting the dose of any research in rats when age is a crucial factor. PMID:23930179

  19. A Rat Excised Larynx Model of Vocal Fold Scar

    ERIC Educational Resources Information Center

    Welham, Nathan V.; Montequin, Douglas W.; Tateya, Ichiro; Tateya, Tomoko; Choi, Seong Hee; Bless, Diane M.

    2009-01-01

    Purpose: To develop and evaluate a rat excised larynx model for the measurement of acoustic, aerodynamic, and vocal fold vibratory changes resulting from vocal fold scar. Method: Twenty-four 4-month-old male Sprague-Dawley rats were assigned to 1 of 4 experimental groups: chronic vocal fold scar, chronic vocal fold scar treated with 100-ng basic…

  20. IMMUNE ALTERATIONS IN RATS FOLLOWING SUBACUTE EXPOSURE TO TRIBUTYLTIN OXIDE

    EPA Science Inventory

    Adult male Fischer 344 rats were dosed by oral gavage with bis(tri-n-butyltin) oxide (TBTO) in peanut oil on ten consecutive days, at dosages ranging from 1.25 to 15 mg/kg/day. ther groups of rats were dosed daily for 10 days by oral gavage with cyclophosphamide (CY) at dosages r...

  1. SKELETAL DEVELOPMENT FOLLOWING HEAT EXPOSURE IN THE RAT

    EPA Science Inventory

    The effects of gestation day (GD) 10 heat exposure in the rat were studied to determine the temperature-response relationship for the induction of skeletal and other defects. onscious pregnant rats were exposed to various temperatures in a warm air chamber. hose animals whose cor...

  2. THE EFFECT OF IMIDAN ADMINISTERED TO PREGNANT RATS

    EPA Science Inventory

    The purpose of this study was to evaluate the teratogenic potential of Imidan in Wistar rats. Accordingly, groups of pregnant Wistar rats received Imidan by either a single or multiple dose protocol and their fetuses were examined for gross, soft tissue, and skeletal defects. In ...

  3. Real-time application of the Rat Grimace Scale as a welfare refinement in laboratory rats

    PubMed Central

    Leung, Vivian; Zhang, Emily; Pang, Daniel SJ

    2016-01-01

    Rodent grimace scales have been recently validated for pain assessment, allowing evaluation of facial expressions associated with pain. The standard scoring method is retrospective, limiting its application beyond pain research. This study aimed to assess if real-time application of the Rat Grimace Scale (RGS) could reliably and accurately assess pain in rats when compared to the standard method. Thirty-two male and female Sprague-Dawley rats were block randomized into three treatment groups: buprenorphine (0.03 mg/kg, subcutaneously), multimodal analgesia (buprenorphine [0.03 mg/kg] and meloxicam [2 mg/kg], subcutaneously), or saline, followed by intra-plantar carrageenan. Real-time observations (interval and point) were compared to the standard RGS method using concurrent video-recordings. Real-time interval observations reflected the results from the standard RGS method by successfully discriminating between analgesia and saline treatments. Real-time point observations showed poor discrimination between treatments. Real-time observations showed minimal bias (<0.1) and acceptable limits of agreement. These results indicate that applying the RGS in real-time through an interval scoring method is feasible and effective, allowing refinement of laboratory rat welfare through rapid identification of pain and early intervention. PMID:27530823

  4. Real-time application of the Rat Grimace Scale as a welfare refinement in laboratory rats.

    PubMed

    Leung, Vivian; Zhang, Emily; Pang, Daniel Sj

    2016-01-01

    Rodent grimace scales have been recently validated for pain assessment, allowing evaluation of facial expressions associated with pain. The standard scoring method is retrospective, limiting its application beyond pain research. This study aimed to assess if real-time application of the Rat Grimace Scale (RGS) could reliably and accurately assess pain in rats when compared to the standard method. Thirty-two male and female Sprague-Dawley rats were block randomized into three treatment groups: buprenorphine (0.03 mg/kg, subcutaneously), multimodal analgesia (buprenorphine [0.03 mg/kg] and meloxicam [2 mg/kg], subcutaneously), or saline, followed by intra-plantar carrageenan. Real-time observations (interval and point) were compared to the standard RGS method using concurrent video-recordings. Real-time interval observations reflected the results from the standard RGS method by successfully discriminating between analgesia and saline treatments. Real-time point observations showed poor discrimination between treatments. Real-time observations showed minimal bias (<0.1) and acceptable limits of agreement. These results indicate that applying the RGS in real-time through an interval scoring method is feasible and effective, allowing refinement of laboratory rat welfare through rapid identification of pain and early intervention. PMID:27530823

  5. Calcium balance in mature male rats with unloaded hindlimbs

    NASA Technical Reports Server (NTRS)

    Navidi, Meena; Evans, Juliann; Wolinsky, Ira; Arnaud, Sara B.

    2004-01-01

    BACKGROUND: Calcium balances, regulated by the calcium endocrine system, are negative during spaceflight but have not been reported in flight simulation models using fully mature small animals. METHODS: We conducted two calcium (Ca) balance studies in 6-mo-old male rats exposed to a model that unloads the hindlimbs (HU) for 4 wk. Control (C) and HU rats were fed diets with 0.5% Ca in the first and 0.1% Ca in the second study. Housing in metabolic cages enabled daily food and water intake measurements as well as collections of urine and fecal specimens. At necropsy, blood was obtained for measures of Ca-regulating hormones. RESULTS: Both C and HU rats adjusted to housing and diets with decreases in body weight and negative Ca balances during the first week of each experiment. Thereafter, averages of Ca balances were more negative in the unloaded rats than controls: -8.1 vs. -1.6 mg x d(-1) in rats fed 0.5% (p < 0.05). This difference was not due to urinary Ca excretion since it was lower in HU than C rats (1.27 +/- 0.51 mg x d(-1) vs. 2.35 +/- 0.82 mg x d(-1), p < 0.05). Fecal Ca in HU rats exceeded dietary Ca by 4-7%, Restricting dietary Ca to 0.1% was followed by an increase in serum 1,25-dihydroxyvitamin D (1,25-D) and greater intestinal Ca absorption than in rats fed 0.5% Ca. Ca balances in rats fed 0.1% Ca were also more negative in HU than C rats (-2.4 vs. -0.03 mg x d(-1), p < 0.05). Parathyroid hormone (PTH) was suppressed and 1,25-D increased in HU rats fed 0.5% Ca. C rats fed 0.1% Ca had increased PTH and 1,25-D was the same as in the HU group. CONCLUSION: After adaptation, Ca balances were more negative in mature male rats with unloaded hindlimbs than controls, an effect from increased secretion and loss of endogenous fecal Ca associated with increased 1,25-D in Ca-replete and Ca-restricted rats.

  6. High alcohol intake in female Sardinian alcohol-preferring rats.

    PubMed

    Loi, Barbara; Colombo, Giancarlo; Maccioni, Paola; Carai, Mauro A M; Franconi, Flavia; Gessa, Gian Luigi

    2014-06-01

    Sardinian alcohol-preferring (sP) rats have been selectively bred for high alcohol preference and consumption. When exposed to the standard, home cage 2-bottle "alcohol (10%, v/v) vs. water" choice regimen with continuous access, male sP rats consume daily approximately 6 g/kg alcohol. Conversely, when exposed to the intermittent (once every other day) access to 2 bottles containing alcohol (20%, v/v) and water, respectively, male sP rats display marked increases in daily alcohol intake and signs of alcohol intoxication and "behavioral" dependence. The present study was designed to assess alcohol intake in female sP rats exposed, under the 2-bottle choice regimen, to (a) 10% (v/v) alcohol with continuous access (CA10%), (b) 10% (v/v) alcohol with intermittent access (IA10%), (c) 20% (v/v) alcohol with continuous access (CA20%), and (d) 20% (v/v) alcohol with intermittent access (IA20%). Male sP rats (exposed to CA10% and IA20% conditions) were included for comparison. Over 20 daily drinking sessions, daily alcohol intake in female CA10% and IA20% rats averaged 7.0 and 9.6 g/kg, respectively. The rank of alcohol intake was IA20% > IA10% = CA20% > CA10%. Conversely, daily alcohol intake in male CA10% and IA20% rats averaged 6.0 and 8.2 g/kg, respectively. Comparison of female and male rats yielded the following rank of alcohol intake: female IA20% > male IA20% > female CA10% ≥ male CA10%. An additional experiment found that alcohol drinking during the first hour of the drinking session produced mean blood alcohol levels of 35-40 mg% and 85-100 mg% in the CA10% and IA20% rats, respectively. These results (a) extend to female sP rats previous data demonstrating the capacity of the IA20% condition to markedly escalate alcohol drinking, and (b) demonstrate that female sP rats consume more alcohol than male sP rats. This sex difference is more evident under the IA20% condition, suggesting that female sP rats are highly sensitive to the promoting effect

  7. Insular Cortex and Consummatory Successive Negative Contrast in the Rat

    PubMed Central

    Lin, Jian-You; Roman, Christopher; Reilly, Steve

    2009-01-01

    Rats that are expecting a high value reward (e.g., 1.0 M sucrose) show an exaggerated underresponding when they are instead given a low value reward (e.g., 0.15% saccharin), an effect termed successive negative contrast (SNC). In the present experiment, insular cortex-lesioned (ICX) rats showed normal responsivity to sucrose and saccharin prior to the reward downshift. However, when switched from sucrose to saccharin during the postshift trials these rats displayed no evidence of SNC. Indeed, over the downshift trials these ICX rats consistently drank more saccharin than the ICX rats maintained on saccharin throughout the experiment. Potential interpretations are discussed including a lesion-induced impairment in the ability to accurately recognize the novelty of the postshift saccharin stimulus. PMID:19634939

  8. Chronological and morphological study of heart development in the rat.

    PubMed

    Marcela, Salazar García; Cristina, Revilla Monsalve María; Angel, Palomino Garibay Miguel; Manuel, Arteaga Martínez; Sofía, Díaz-Cintra; Patricia, De La Rosa-Santander; Bladimir, Roque-Ramírez; Concepción, Sánchez Gómez

    2012-08-01

    Adult and embryonic laboratory rats have been used as a mammalian model organism in biomedical research, descriptive and experimental cardiac embryology, and experimental teratology. There have been, however, considerable variations and discrepancies concerning the developmental staging of the rat embryo in the reported literature, which have resulted in several controversies and inconsistencies. Therefore, we carried out a careful anatomical and histological study of rat cardiac morphogenesis from the premorphogenetic period to the mature heart in a newborn pup. A correlation between the chronology and morphological features of the heart and embryo or newborn was made. We provide a simple and comprehensive guide relating the developmental timing and fate of the embryonic components of the heart and their morphological changes in the rat based on in vivo labeling studies in the chick. We also compare the timing of heart development in rats, humans, and mice. PMID:22715162

  9. Urinary excretion of guanidinoacetic acid in rats with diabetic nephropathy.

    PubMed

    Kiyatake, I; Nakamura, T; Koide, H

    2006-01-01

    Urinary guanidinoacetic acid (GAA) is a sensitive marker for gentamicin nephrotoxicity in rats. This study assesses the usefulness of GAA concentrations in the diagnosis of renal tubular injury in diabetic nephropathy. Serum, urine, and renal cortex samples were obtained from rats 1, 2, and 3 weeks after streptozotocin injection (65 mg/kg body weight). Guanidinoacetic acid levels were measured by high-performance liquid chromatography. N-acetyl-beta-D-glucosaminidase (NAG) activity in urine was determined by an enzymatic method. GAA levels in serum, urine, and renal cortex were significantly decreased in diabetic rats compared with those in control rats. In contrast, urinary NAG activity was significantly increased in diabetic rats. Decreases in serum, urine, and renal cortical GAA levels were attenuated by insulin treatment. These results indicate that a high serum glucose level may affect GAA synthesis in the renal cortex and that urinary GAA may be a clinically useful indicator of renal tubular injury in diabetic nephropathy. PMID:16538977

  10. [Age and the course of nephrotoxic nephritis in rats].

    PubMed

    Samoĭlova, Z T; Kliukina, S S

    1978-12-01

    In experiments on two groups of mongrel rats (4 weeks old and 4 months old) with induced nephrotoxic nephritis it was revealed that in comparison with adult rats the course of nephritis in ratlings was characterized by lesser proteinuria, selective in nature, by lesser reducticn of endogenous creatinine clearance and diuresis. The acido- and ammo-niogenesis decreased in ratlings and adult rats to the same extent. Morphological changes in the kidneys of ratlings were less pronounced than in adult animals, and were mostly localized in the convoluted tubules. The level of DNA-synthetic activity of the epithelial nuclei of the glomeruli prevailed over this index of the convoluted tubules epithelium. The weight index of the kidneys increased less in ratlings with nephritis than in adult rats. beta-lipoproteinemia in ratlings increased 8 times. Normalization of the urine and blood indices occurred more rapidly in ratlings than in adult rats. PMID:31956

  11. Cognitive bias in rats is not influenced by oxytocin

    PubMed Central

    McGuire, Molly C.; Williams, Keith L.; Welling, Lisa L. M.; Vonk, Jennifer

    2015-01-01

    The effect of oxytocin on cognitive bias was investigated in rats in a modified conditioned place preference paradigm. Fifteen male rats were trained to discriminate between two different cue combinations, one paired with palatable foods (reward training), and the other paired with unpalatable food (aversive training). Next, their reactions to two ambiguous cue combinations were evaluated and their latency to contact the goal pot recorded. Rats were injected with either oxytocin (OT) or saline with the prediction that rats administered OT would display a shorter average latency to approach on ambiguous trials. There was no significant difference between latencies to approach on ambiguous trials compared to reward trials, but the rats were significantly slower on the aversive compared to the ambiguous conditions. Oxytocin did not affect approach time; however, it was unclear, after follow-up testing, whether the OT doses tested were sufficient to produce the desired effects on cognitive bias. Future research should consider this possibility. PMID:26388811

  12. The comparative metabolism of diisopropyl methylphosphonate in mink and rats.

    PubMed

    Weiss, D J; Geary, R S; Wustenberg, W; Bucci, T J; Perman, V; Baumel, I P; Dacre, J C

    1994-10-01

    This study reports the metabolism of carbon-14labeled diisopropyl methylphosphonate (DIMP) in mink and rats, undertaken to better understand the dose-related mortality reported for mink in a previous study. In both male and female mink and rats, DIMP was rapidly absorbed after oral administration; it was metabolized by a saturable pathway to a single metabolite, isopropyl methylphosphonate (IMPA), which was rapidly excreted, primarily in the urine (90%). Fecal radioactivity, also identified as IMPA, was 1.7-3.1% of the administered dose. Female rats had a slower rate of conversion of DIMP to IMPA and less total excretion of IMPA than male rats. Metabolism of DIMP administered intravenously was not very different from that given orally in both species. These data indicate that mink absorb, metabolize, and excrete DIMP (as IMPA) in a manner very similar to mice, rats, and dogs. PMID:7944557

  13. Voltametric assessment of brain nitric oxide during heatstroke in rats.

    PubMed

    Canini, F; Bourdon, L; Cespuglio, R; Buguet, A

    1997-08-01

    Anesthetized rats exposed to a high ambient temperature develop heatstroke with brain ischemia. Since nitric oxide (NO) plays an important role during normothermic ischemia, its cortical and cerebellar production were continuously assessed in pentobarbital anesthetized rats exposed to heat by using differential pulsed voltammetry. After 60 min at thermoneutrality, the rats were submitted to an ambient temperature of 40 degrees C until death. After 60 min in the heat, the rats were injected intraperitoneally with saline, MK801 (1 mg.kg(-1)), an antagonist of N-methyl-D-aspartate (NMDA) receptors, or L-arginine p-nitroanilide (L-ANA; 100 mg.kg(-1)), an inhibitor of NO synthase. Just before death, a 70% increase in NO production was observed in both the cerebellum and the cortex of saline-treated rats. The cortical increase in NO was not modified by MK801 while the NO signal was suppressed by L-ANA. PMID:9291142

  14. Metabolic and hormonal responses to exercise in partially hepatectomised rats.

    PubMed

    Lavoie, J M; Warren, C; Arcelin, K; Latour, M G; Désy, F; Shinoda, M; Ethier, C; Gascon-Barré, M

    1998-06-01

    To characterise how the liver affects metabolic and hormonal exercise responses, hepatectomised (70%; HX) rats were submitted to a 30- or 50-min treadmill exercise (26 m/min, 0% slope) 48 hr or 7 days after surgery (reduced or normal liver mass, respectively). To determine whether metabolic effects of liver mass reduction during exercise were caused by reduced capacity of the liver to produce glucose, metabolic and hormonal responses to the same exercise protocol were measured in 48-hr HX rats. Euglycemia, maintained by exogenous glucose infusion, produced attenuated lactate, insulin, and glucagon values in 48-hr HX rats but did not affect FFA, glycerol, and plasma catecholamine responses. Results indicate that metabolic and hormonal exercise responses are amplified in 48-hr HX rats. Maintaining euglycemia in 48-hr HX rats during exercise does not reduce all responses. Intrahepatic events, similar to those in a short-term (48-hr) HX liver, may influence metabolic and hormonal exercise responses. PMID:9615872

  15. Empathy and pro-social behavior in rats.

    PubMed

    Ben-Ami Bartal, Inbal; Decety, Jean; Mason, Peggy

    2011-12-01

    Whereas human pro-social behavior is often driven by empathic concern for another, it is unclear whether nonprimate mammals experience a similar motivational state. To test for empathically motivated pro-social behavior in rodents, we placed a free rat in an arena with a cagemate trapped in a restrainer. After several sessions, the free rat learned to intentionally and quickly open the restrainer and free the cagemate. Rats did not open empty or object-containing restrainers. They freed cagemates even when social contact was prevented. When liberating a cagemate was pitted against chocolate contained within a second restrainer, rats opened both restrainers and typically shared the chocolate. Thus, rats behave pro-socially in response to a conspecific's distress, providing strong evidence for biological roots of empathically motivated helping behavior. PMID:22158823

  16. Serotonin transporter deficiency in rats contributes to impaired object memory.

    PubMed

    Olivier, J D A; Jans, L A W; Blokland, A; Broers, N J; Homberg, J R; Ellenbroek, B A; Cools, A R

    2009-11-01

    Serotonin is well known for its role in affection, but less known for its role in cognition. The serotonin transporter (SERT) has an essential role in serotonergic neurotransmission as it determines the magnitude and duration of the serotonin signal in the synaptic cleft. There is evidence to suggest that homozygous SERT knockout rats (SERT(-/-)), as well as humans with the short SERT allele, show stronger cognitive effects than wild-type control rats (SERT(+/+)) and humans with the long SERT allele after acute tryptophan depletion. In rats, SERT genotype is known to affect brain serotonin levels, with SERT(-/-) rats having lower intracellular basal serotonin levels than wild-type rats in several brain areas. In the present study, it was investigated whether SERT genotype affects memory performance in an object recognition task with different inter-trial intervals. SERT(-/-), heterozygous SERT knockout (SERT(+/-)) and SERT(+/+) rats were tested in an object recognition test applying an inter-trial interval of 2, 4 and 8 h. SERT(-/-) and SERT(+/-) rats showed impaired object memory with an 8 h inter-trial interval, whereas SERT(+/+) rats showed intact object memory with this inter-trial interval. Although brain serotonin levels cannot fully explain the SERT genotype effect on object memory in rats, these results do indicate that serotonin is an important player in object memory in rats, and that lower intracellular serotonin levels lead to enhanced memory loss. Given its resemblance with the human SERT-linked polymorphic region and propensity to develop depression-like symptoms, our findings may contribute to further understanding of mechanisms underlying cognitive deficits in depression. PMID:19740092

  17. Ventilatory impairment in the dysmyelinated Long Evans shaker (les) rat

    PubMed Central

    Johnson, Rebecca A.; Baker-Herman, Tracy L.; Duncan, Ian D.; Mitchell, Gordon S.

    2010-01-01

    Although respiratory complications significantly contribute to morbidity/mortality in advanced myelin disorders, little is known concerning mechanisms whereby dysmyelination impairs ventilation, or how patients compensate (i.e. plasticity). To establish a model for studies concerning mechanisms of ventilatory impairment/compensation, we tested the hypotheses that respiratory function progressively declines in a model of CNS dysmyelination, the Long Evans shaker rat (les). The observed impairment is associated with abnormal inspiratory neural output. Minimal myelin staining was found throughout the CNS of les rats, including the brainstem and cervical bulbospinal tracts. Ventilation (via whole-body plethysmography) and phrenic motor output were assessed in les and wild-type (WT) rats during baseline, hypoxia (11% O2) and hypercapnia (7% CO2). Hypercapnic ventilatory responses were similar in young adult les and WT rats (2 months old); in hypoxia, rats exhibited seizure-like activity with sustained apneas. However, 5–6 month old les rats exhibited decreased breathing frequencies, mean inspiratory flow (VT/TI) and ventilation (V̇E) during baseline and hypercapnia. Although phrenic motor output exhibited normal burst frequency and amplitude in 5–6 month old les rats, intra-burst activity was abnormal. In WT rats, phrenic activity was progressive and augmenting; in les rats, phrenic activity was decrementing with asynchronized, multipeaked activity. Thus, although ventilatory capacity is maintained in young, dysmyelinated rats, ventilatory impairment develops with age, possibly through discoordination in respiratory motor output. This study is the first reporting age-related breathing abnormalities in a rodent dysmyelination model, and provides the foundation for mechanistic studies of respiratory insufficiency and therapeutic interventions. PMID:20542092

  18. Ventilatory impairment in the dysmyelinated Long Evans shaker rat.

    PubMed

    Johnson, R A; Baker-Herman, T L; Duncan, I D; Mitchell, G S

    2010-09-01

    Although respiratory complications significantly contribute to morbidity/mortality in advanced myelin disorders, little is known concerning mechanisms whereby dysmyelination impairs ventilation, or how patients compensate (i.e. plasticity). To establish a model for studies concerning mechanisms of ventilatory impairment/compensation, we tested the hypotheses that respiratory function progressively declines in a model of CNS dysmyelination, the Long Evans shaker rat (les). The observed impairment is associated with abnormal inspiratory neural output. Minimal myelin staining was found throughout the CNS of les rats, including the brainstem and cervical bulbospinal tracts. Ventilation (via whole-body plethysmography) and phrenic motor output were assessed in les and wild-type (WT) rats during baseline, hypoxia (11% O(2)) and hypercapnia (7% CO(2)). Hypercapnic ventilatory responses were similar in young adult les and WT rats (2 months old); in hypoxia, rats exhibited seizure-like activity with sustained apneas. However, 5-6 month old les rats exhibited decreased breathing frequencies, mean inspiratory flow (V(T)/T(I)) and ventilation (V (E)) during baseline and hypercapnia. Although phrenic motor output exhibited normal burst frequency and amplitude in 5-6 month old les rats, intra-burst activity was abnormal. In WT rats, phrenic activity was progressive and augmenting; in les rats, phrenic activity was decrementing with asynchronized, multipeaked activity. Thus, although ventilatory capacity is maintained in young, dysmyelinated rats, ventilatory impairment develops with age, possibly through discoordination in respiratory motor output. This study is the first reporting age-related breathing abnormalities in a rodent dysmyelination model, and provides the foundation for mechanistic studies of respiratory insufficiency and therapeutic interventions. PMID:20542092

  19. Microarray analysis of thioacetamide-treated type 1 diabetic rats

    SciTech Connect

    Devi, Sachin S.; Mehendale, Harihara M. . E-mail: mehendale@ulm.edu

    2006-04-01

    It is well known that diabetes imparts high sensitivity to numerous hepatotoxicants. Previously, we have shown that a normally non-lethal dose of thioacetamide (TA, 300 mg/kg) causes 90% mortality in type 1 diabetic (DB) rats due to inhibited tissue repair allowing progression of liver injury. On the other hand, DB rats exposed to 30 mg TA/kg exhibit delayed tissue repair and delayed recovery from injury. The objective of this study was to investigate the mechanism of impaired tissue repair and progression of liver injury in TA-treated DB rats by using cDNA microarray. Gene expression pattern was examined at 0, 6, and 12 h after TA challenge, and selected mechanistic leads from microarray experiments were confirmed by real-time RT-PCR and further investigated at protein level over the time course of 0 to 36 h after TA treatment. Diabetic condition itself increased gene expression of proteases and decreased gene expression of protease inhibitors. Administration of 300 mg TA/kg to DB rats further elevated gene expression of proteases and suppressed gene expression of protease inhibitors, explaining progression of liver injury in DB rats after TA treatment. Inhibited expression of genes involved in cell division cycle (cyclin D1, IGFBP-1, ras, E2F) was observed after exposure of DB rats to 300 mg TA/kg, explaining inhibited tissue repair in these rats. On the other hand, DB rats receiving 30 mg TA/kg exhibit delayed expression of genes involved in cell division cycle, explaining delayed tissue repair in these rats. In conclusion, impaired cyclin D1 signaling along with increased proteases and decreased protease inhibitors may explain impaired tissue repair that leads to progression of liver injury initiated by TA in DB rats.

  20. Rats with Chronic, Stable Pulmonary Hypertension Tolerate Low Dose Sevoflurane Inhalation as Well as Normal Rats Do

    PubMed Central

    Qin, Gang; Luo, Hui; Liu, Xiao; Zhang, Fan; Ye, Zhi; Zhang, Junjie; Wang, E.

    2016-01-01

    Background The effects of low concentration of sevoflurane on right ventricular (RV) function and intracellular calcium in the setting of pulmonary arterial hypertension (PAH) have not been investigated clearly. We aim to study these effects and associated signaling pathways in rats with PAH. Methods Hemodynamics were assessed with or without sevoflurane inhalation in established PAH rats. We analysis the classic RV function parameters and RV-PA coupling efficiency using steady-state PV loop recordings. The protein levels of SERCA2, PLB and p-PLB expression was analyzed by western blot to assess their relevance in PAH. Results Rats with PAH presented with RV hypertrophy and increased pulmonary arterial pressure. The values of Ea, R/L ratio, ESP, SW, PRSW, +dP/dtmax and the slope of the dP/dtmax-EDV relationship increased significantly in PAH rats (P<0.05). Sevoflurane induced a concentration-dependent decrease of systemic and pulmonary blood pressure, HR, RV contractility, and increased the R/L ratio in both groups. Sevoflurane reduced the expression of SERCA2 and increased the expression of PLB in both groups. Interestingly, sevoflurane only reduced the p-PLB/PLB ratio in PAH rats, not in normal rats. Conclusions Rats with chronic, stable pulmonary hypertension tolerate low concentrations of sevoflurane inhalation as well as normal rats do. It may be related to the modulation of the SERCA2-PLB signaling pathway. PMID:27144451

  1. Comparison of starvation and elastase models of emphysema in the rat

    SciTech Connect

    Harkema, J.R.; Mauderly, J.L.; Gregory, R.E.; Pickrell, J.A.

    1984-01-01

    Starvation and elastase-induced changes in rat lung structure, biochemistry, and function were compared as models of human pulmonary emphysema. Ten-week-old male rats were instilled intratracheally with either porcine pancreatic elastase in saline (E) or with saline alone. A group of the saline-instilled rats were fed one third of their normal food intake until a 45% loss of body weight occurred (S). The remaining saline-instilled rats served as control animals (C). Post-treatment evaluations included in vivo respiratory function, lung histopathologic and morphometric analyses, lung tissue proteinolytic activity, and lung collagen. The E rats had in vivo respiratory function changes more similar to human emphysema than those of S rats. All lung volume subdivisions were decreased in S rats and increased in E rats. The volume-pressure curve of S rats was shifted to the right of the C curve, whereas that of E rats was shifted to the left. Forced expiratory flow rates of E rats were decreased at all lung volumes, but those of S rats were not. Both E and S rats had larger terminal air spaces and less alveolar surface area than did C rats. The S rats had more collagen per gram lung and higher proteinolytic activity than did C or E rats. These results show that, although starvation induces some changes characteristic of human emphysema, elastase-treatment provides a model more similar to the human disease. 44 references, 5 figures, 4 tables.

  2. Effect of spironolactone on the renin-aldosterone system in rats.

    PubMed

    Jiménez, W; Martínez-Pardo, A; Arroyo, V; Gaya, J; Rivera, F

    1988-09-01

    PRA, PRC and the plasma concentration of aldosterone (Aldo) were measured in rats (Sp-rats) receiving a daily sc injection of Spironolactone, (Sp, 20 mg in olive oil) and in control rats (C-rats) receiving olive oil only. Animals were studied one day after starting treatment, 5 days on treatment or after 5 weeks on the study. PRA, PRC and Aldo were significantly increased in Sp-rats as compared to C-rats throughout all the study. In additional Sp-rats and C-rats, the urine volume, serum Na+ and K+ concentration, Na+ and K+ intake and the urinary excretion of Na+, K+ and aldosterone-18-glucuronide (UAldV) were serially measured during 5 weeks. The total radioactivity plasma clearance after an i.v. bolus injection of 3H-aldosterone was subsequently measured in (5 Sp-rats and 5 C-rats). No significant differences in serum Na+ and K+ concentration and in Na+ and K+ balance were observed between Sp-rats and C-rats. UAldV was significantly higher in Sp-rats than in C-rats during all the study. After 5 weeks on treatment the total radioactivity plasma clearance was significantly higher in Sp-rats than in C-rats. These results indicate that Sp, at high dosage, stimulates renin release and aldosterone secretion by a mechanism unrelated to alterations in Na+ and K+ balance. PMID:3068736

  3. Characterization of muscarinic receptors in rat kidney.

    PubMed

    Blankesteijn, W M; Siero, H L; Rodrigues de Miranda, J F; van Megen, Y J; Russel, F G

    1993-01-01

    Muscarinic receptors in mammalian kidney seem to be involved in diuresis. In this study we give a detailed characterization of receptors in rat kidney. Specific binding of [3H](-)-quinuclidinylbenzilate ([3H]QNB) to membranes of rat kidney cortex was saturable and of high affinity. A dissociation constant of 0.063 +/- 0.003 nM and a receptor density of 1.46 +/- 0.07 pmol/g wet weight were obtained. The dissociation kinetics could be best described by assuming a mono-exponential function (k-1 = (0.52 +/- 0.1) x 10(-4) s-1). The binding of [3H]QNB reached a maximum in 60 min at 0.6 nM at 37 degrees C. Competition experiments with the enantiomers of benzetimide confirmed the muscarinic nature of the [3H]QNB binding sites. The inhibition constants of pirenzepine (0.23 +/- 0.02 microM), (+-)-hexahydrosiladifenidol (0.040 +/- 0.002 microM), AF-DX 116 (1.45 +/- 0.07 microM), methoctramine (1.67 +/- 0.02 microM) and gallamine (78 +/- 3 microM) classified this receptor as an M3 receptor. Inhibition of [3H]QNB binding by the agonists methylfurtrethonium, arecoline, isoarecoline methiodide, arecaidine propargyl ester and McN-A-343 displayed monophasic inhibition curves. With (+/-)-cis-2-methyl-4-dimethylaminomethyl-1,3- dioxolane methiodide in two out of four experiments a small (11%) population of high affinity agonist sites could be detected. The potassium sparing diuretic amiloride inhibited [3H]QNB binding (36 +/- 3 microM). Although in a way related to the amiloride binding site, the muscarinic receptors in rat kidney are unlikely to be the primary target of diuretic action of this drug. PMID:8420789

  4. Quantitative Ultrasound Assessment of the Rat Cervix

    PubMed Central

    McFarlin, Barbara L.; O’Brien, William D.; Oelze, Michael L.; Zachary, James F.; White-Traut, Rosemary C.

    2009-01-01

    Objective The purpose of this research was to detect cervical ripening with a new quantitative ultrasound technique. Methods Cervices of 13 nonpregnant and 65 timed pregnant (days 15, 17, 19, 20, and 21 of pregnancy) Sprague Dawley rats were scanned ex vivo with a 70-MHz ultrasound transducer. Ultrasound scatterer property estimates (scatterer diameter [SD], acoustic concentration [AC], and scatterer strength factor [SSF]) from the cervices were quantified and then compared to hydroxyproline and water content. Insertion loss (attenuation) was measured in 3 rats in each of the 6 groups. Discriminant analysis was used to predict gestational age group (cervical ripening) from the ultrasound variables SD, SSF, and AC. Results Differences were observed between the groups (SD, AC, and SSF; P < .0001). Quantitative ultrasound measures changed as the cervix ripened: (1) SD increased from days 15 to 21; (2) AC decreased from days 15 to 21; and (3) SSF was the greatest in the nonpregnant group and the least in the day 21 group. Cervix hydroxyproline content increased as pregnancy progressed (P < .003) and correlated with group, SD, AC, and SSF (P < .001). Discriminant analysis of ultrasound variables predicted 56.4% of gestational group assignment (P < .001) and increased to 77% within 2 days of the predicted analysis. Cervix insertion loss was greatest for the nonpregnant group and least for the day 21 group. Conclusions Quantitative ultrasound predicted cervical ripening in the rat cervix, but before use in humans, quantitative ultrasound will need to predict gestational age in the later days of gestation with more precision. PMID:16870896

  5. Retroendocytosis of insulin in rat adipocytes

    SciTech Connect

    Levy, J.R.; Olefsky, J.M.

    1986-08-01

    A variety of ligands internalized by receptor-mediated endocytosis follow a short circuit pathway that does not lead to degradation but results in rapid exocytosis of intact ligand, a process termed retroendocytosis. We studied the time course of (/sup 125/I)iodoinsulin processing and retroendocytosis after internalization in isolated rat adipocytes. After steady state binding and internalization, surface receptor-bound insulin was removed by exposing cells to a low pH at low temperatures. The cells containing internalized (/sup 125/I)iodoinsulin were reincubated in fresh medium; subsequently, the radioactivity remaining within the cells and released into the medium were analyzed at various times by trichloroacetic acid (TCA) precipitation, Sephadex G-50 gel filtration, and reverse phase HPLC. Cell-associated radioactivity progressively decreased after reincubation in 37 C buffer, with 50% released in 9 min and 85% by 45 min. In the media, TCA-precipitable material appeared quickly, with a t1/2 of 2 min, and plateaued by 10 min. TCA-soluble material was released continually throughout the 45-min period. The release of both TCA-precipitable and TCA-soluble material was temperature and energy dependent. Sephadex G-50 chromatography demonstrated the loss of insulin from the intracellular pool and its appearance in the medium with a time course similar to that of TCA-precipitable material. Reverse phase HPLC demonstrated that the intracellular and medium radioactivity eluting in peak II (insulin peak) on Sephadex G-50 was composed of both intact insulin and intermediates. After the internalization of insulin, rat adipocytes release not only small mol wt degradation products of insulin, but also insulin intermediates and intact insulin. The rate of retroendocytosis reported here is almost identical to the rate of insulin receptor recycling in rat adipocytes.

  6. Distribution of prosaposin in rat lymphatic tissues.

    PubMed

    Shimokawa, Tetsuya; Nabeka, Hiroaki; Yamamiya, Kimiko; Wakisaka, Hiroyuki; Takeuchi, Takashi; Kobayashi, Naoto; Matsuda, Seiji

    2013-06-01

    Prosaposin (PSAP) is as a trophic factor and an activator protein for sphingolipid hydrolase in lysosomes. We generated a specific antibody to PSAP and examined the spatiotemporal distribution of PSAP-immunoreactive (PSAP-IR) cells in the lymphatic tissues of Wistar rats. Immunoblots of tissue homogenates separated electrophoretically showed a single band for PSAP in brain but two bands in spleen. PSAP-IR cells were distributed in both the red and white pulp of the spleen, in both the cortex and medulla of the thymus and in mesenteric lymph nodes. Many PSAP-IR cells were found in the dome portion of Peyer's patches and the number of PSAP-IR cells increased with the age of the rat. To identify the PSAP-IR cells, double- and triple-immunostainings were performed with antibodies against PSAP, CD68 and CD1d. The large number of double- and triple-positive cells suggested that antigen-presenting cells contained much PSAP in these lymphatic tissues. Intense expression of PSAP mRNA, examined by in situ hybridisation, was observed in the red pulp and corona of the spleen. In rats, the PSAP gene generates two alternative splicing forms of mRNA: Pro+9 containing a 9-base insertion and Pro+0 without the insertion. We examined the expression patterns of the alternative splicing forms of PSAP mRNA in the spleen. The presence of both types of mRNA (Pro+9 and Pro+0) indicated that the spleen contains various types of prosaposin-producing and/or secreting cells. These findings suggest diverse functions for PSAP in the immune system. PMID:23420452

  7. Fate of inhaled azodicarbonamide in rats

    SciTech Connect

    Mewhinney, J.A.; Ayres, P.H.; Bechtold, W.E.; Dutcher, J.S.; Cheng, Y.S.; Bond, J.A.; Medinsky, M.A.; Henderson, R.F.; Birnbaum, L.S.

    1987-04-01

    Azodicarbonamide (ADA) is widely used as a blowing agent in the manufacture of expanded foam plastics, as an aging and bleaching agent in flour, and as a bread dough conditioner. Human exposures have been reported during manufacture as well as during use. Groups of male F344/N rats were administered ADA by gavage, by intratracheal instillation, and by inhalation exposure to determine the disposition and modes of excretion of ADA and its metabolites. At 72 hr following gavage, 30% of the administered ADA was absorbed whereas following intratracheal instillation, absorption was 90%. Comparison between groups of rats exposed by inhalation to ADA to achieve body burdens of 24 or 1230 micrograms showed no significant differences in modes or rates of excretion of (/sup 14/C)ADA equivalents. ADA was readily converted to biurea under physiological conditions and biurea was the only /sup 14/C-labeled compound present in excreta. (/sup 14/C)ADA equivalents were present in all examined tissues immediately after inhalation exposure, and clearance half-times on the order of 1 day were evident for all tissues investigated. Storage depots for (/sup 14/C)ADA equivalents were not observed. The rate of buildup of (/sup 14/C)ADA equivalents in blood was linearly related to the lung content as measured from rats withdrawn at selected times during a 6-hr inhalation exposure at an aerosol concentration of 25 micrograms ADA/liter. In a study extending 102 days after exposure, retention of (/sup 14/C)ADA equivalents in tissues was described by a two-component negative exponential function. The results from this study indicate that upon inhalation, ADA is rapidly converted to biurea and that biurea is then eliminated rapidly from all tissues with the majority of the elimination via the urine.

  8. Metabolism of triiodothyronine in rat hepatocytes.

    PubMed

    Rooda, S J; Otten, M H; van Loon, M A; Kaptein, E; Visser, T J

    1989-10-01

    The metabolism of T3 by isolated rat hepatocytes was analyzed by Sephadex LH-20 chromatography, HPLC, and RIA for T3 sulfate (T3S) and 3,3'-diiodothyronine (3,3'-T2). Type I iodothyronine deiodinase activity was inhibited with propylthiouracil (PTU), and phenol sulfotransferase activity by SO4(2-) depletion or with competitive substrates or inhibitors. Under normal conditions, labeled T3 glucuronide and I- were the main products of [3'-125I]T3 metabolism. Iodide production was decreased by inhibition (PTU) or saturation (greater than 100 nM T3) of type I deiodinase, which was accompanied by the accumulation of T3S and 3,3'-T2S. Inhibition of phenol sulfotransferase resulted in decreased iodide production, which was associated with an accumulation of 3,3'-T2 and 3,3'-T2 glucuronide, independent of PTU. Formation of 3,3'-T2 and its conjugates was only observed at T3 substrate concentrations below 10 nM. Thus, T3 is metabolized in rat liver cells by three quantitatively important pathways: glucuronidation, sulfation, and direct inner ring deiodination. Whereas T3 glucuronide is not further metabolized in the cultures, T3S is rapidly deiodinated by the type I enzyme. As confirmed by incubations with isolated rat liver microsomes, direct inner ring deiodination of T3 is largely mediated by a low Km, PTU-insensitive, type III-like iodothyronine deiodinase, and production of 3,3'-T2 is only observed if its rapid sulfation is prevented. PMID:2791985

  9. Anomalous extracellular diffusion in rat cerebellum.

    PubMed

    Xiao, Fanrong; Hrabe, Jan; Hrabetova, Sabina

    2015-05-01

    Extracellular space (ECS) is a major channel transporting biologically active molecules and drugs in the brain. Diffusion-mediated transport of these substances is hindered by the ECS structure but the microscopic basis of this hindrance is not fully understood. One hypothesis proposes that the hindrance originates in large part from the presence of dead-space (DS) microdomains that can transiently retain diffusing molecules. Because previous theoretical and modeling work reported an initial period of anomalous diffusion in similar environments, we expected that brain regions densely populated by DS microdomains would exhibit anomalous extracellular diffusion. Specifically, we targeted granular layers (GL) of rat and turtle cerebella that are populated with large and geometrically complex glomeruli. The integrative optical imaging (IOI) method was employed to evaluate diffusion of fluorophore-labeled dextran (MW 3000) in GL, and the IOI data analysis was adapted to quantify the anomalous diffusion exponent dw from the IOI records. Diffusion was significantly anomalous in rat GL, where dw reached 4.8. In the geometrically simpler turtle GL, dw was elevated but not robustly anomalous (dw = 2.6). The experimental work was complemented by numerical Monte Carlo simulations of anomalous ECS diffusion in several three-dimensional tissue models containing glomeruli-like structures. It demonstrated that both the duration of transiently anomalous diffusion and the anomalous exponent depend on the size of model glomeruli and the degree of their wrapping. In conclusion, we have found anomalous extracellular diffusion in the GL of rat cerebellum. This finding lends support to the DS microdomain hypothesis. Transiently anomalous diffusion also has a profound effect on the spatiotemporal distribution of molecules released into the ECS, especially at diffusion distances on the order of a few cell diameters, speeding up short-range diffusion-mediated signals in less permeable

  10. Development of exoskeletal robotic limbs for a rat controlled by neural signals based on a vehicular neuro-robotic platform RatCar.

    PubMed

    Fukayama, Osamu; Otsuka, Hiroshi; Hashimoto, Ryuta; Suzuki, Takafumi; Mabuchi, Kunihiko

    2012-01-01

    A pair of exoskeletal limbs for a rat has been developed based on a vehicular Brain-Machine Interface "Rat-Car". The "RatCar" is a whole-body motor prosthesis system for a rat developed by the authors, estimating locomotion velocity according to neural signals pattern to move the rat body by the vehicle instead of its original limbs. In this paper, exoskeletal limbs have displaced the wheels for more natural modality of body control. The system was tested by applying peripheral nerve signals from a behaving rat. PMID:23366238

  11. Cholinergic muscarinic receptors in rat cochlea.

    PubMed

    van Megen, Y J; Klaassen, A B; Rodrigues de Miranda, J F; Kuijpers, W

    1988-11-22

    Specific 3H-1-quinuclidinylbenzilate (3H-1-QNB) binding to rat cochlea homogenates occurs to a homogeneous class of binding sites with Kd = 0.13 +/- 0.01 nM and Bmax = 0.57 +/- 0.07 fmol per cochlea. Binding is stereoselectively inhibited by benzetimide enantiomers. Dexetimide was more effective than levetimide in displacing 3H-1-QNB from its binding sites (Ki = 4 x 10(-10) M and 6.5 x 10(-6) M, respectively). Pirenzepine inhibits 3H-1-QNB binding with low affinity (Ki = 2 x 10(-6) M), classifying the binding sites as muscarinic M2 receptors. PMID:3214711

  12. The pituitary - Aging and spaceflown rats

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Grindeland, R. E.

    1991-01-01

    Decrements in growth hormone (GH) release we observed in two spaceflight experiments and four tail-suspended rat studies mimic age-associated changes in the mammalian pituitary GH system seen by Meites and others. The spaceflight data suggest that formation of high molecular weight bioactive disulfide-linked aggregates of the 20 and 22K monomeric GH forms may be reduced in microgravity, thereby, reducing target tissue activity. Correlative studies to confirm spaceflight as a model for pituitary GH system aging should include: (1) investigation of mechanisms of intracellular hormone packaging, (2) consequences to biological activity of the hormone molecule, and (3) study of intracellular microtubule dynamics.

  13. Effect of aflatoxins on rat peritoneal macrophages.

    PubMed Central

    Cusumano, V; Costa, G B; Seminara, S

    1990-01-01

    Phagocytosis, intracellular killing of Candida albicans, and superoxide production by rat peritoneal macrophages exposed to aflatoxins B1, B2, G1, G2, B2a, and M1 at several times and concentrations were analyzed to evaluate the intensity of a depressive effect for each mycotoxin. All aflatoxins used at very low concentrations had a depressive effect on the functions of macrophages. The biggest impairment of phagocytosis, intracellular killing, and spontaneous superoxide production was observed in macrophages exposed to aflatoxins B1 and M1. PMID:2176448

  14. Optimal response rates in humans and rats

    PubMed Central

    Freestone, David M.; Balcı, Fuat; Simen, Patrick; Church, Russell M.

    2015-01-01

    The analysis of response rates has been highly influential in psychology, giving rise to many prominent theories of learning. There is, however, growing interest in explaining response rates, not as a global response to associations or value, but as a decision about how to space responses in time. Recently, researchers have shown that humans and mice can time a single response optimally, i.e., in a way that maximizes reward. Here, we use the well-established DRL timing task to show that humans and rats come close to optimizing reinforcement rate, but respond systematically faster than they should. PMID:25706545

  15. Corona discharge influences ozone concentrations near rats.

    PubMed

    Goheen, Steven C; Gaither, Kari; Anantatmula, Shantha M; Mong, Gary M; Sasser, Lyle B; Lessor, Delbert

    2004-02-01

    Ozone can be produced by corona discharge either in dry air or when one electrode is submerged in water. Since ozone is toxic, we examined whether ozone production by corona near laboratory animals could reach levels of concern. Male rats were exposed to a corona discharge and the concentration of ozone produced was measured. The resulting concentration of ozone ranged from ambient levels to 250 ppb when animals were located 1 cm from a 10 kV source. Similar ozone concentrations were observed when a grounded water source was present. Possible explanations for, as well as concerns regarding, ozone production under these conditions are discussed. PMID:14735560

  16. Disposition of Naltrexone after Intravenous Bolus Administration in Wistar Rats, Low-Alcohol-Drinking Rats and High-Alcohol-Drinking Rats

    PubMed Central

    Akala, Emmanuel O.; Wang, Hu; Adedoyin, Adedayo

    2010-01-01

    Reports have shown that interspecies differences in the metabolism and pharmacokinetics of naltrexone are a rule rather than exception. However, there is paucity of information on the disposition of naltrexone in selectively bred rat lines that reliably exhibit high and low voluntary alcohol consumption, and are often used to study alcohol-drinking behavior. We have characterized the pharmacokinetic profiles of naltrexone in selectively bred rat lines: high-alcohol-drinking (HAD-1) and low-alcohol-drinking (LAD-1) rats as well as the native Wistar strain. This study was carried out to establish a baseline pharmacokinetic profile of naltrexone in these rats prior to evaluating its pharmacokinetic profile in polymeric controlled-release formulations in our laboratory. The hypothesis is that alcohol-preferring and non-alcohol-preferring lines of rats should differ in the disposition of intravenously administered naltrexone. Naltrexone administration and blood collection were via the jugular vein. In a parallel experiment, naltrexone was administered via the jugular vein, but urine was collected using the Nalgene metabolic cage system. Data were analyzed by a noncompart-mental approach. Results show a high clearance that is close to or higher than hepatic blood flow in all groups (Wistar > LAD-1 > HAD-1, but with a statistically significant difference only between Wistar and HAD-1). Volume of distribution ( ~2.5-3 l/kg) and the half-life ( ~1 h) were similar. Urinary elimination of naltrexone was small, but also showed differences between the rats: HAD-1 > LAD-1 > Wistar, but with a statistically significant difference only between HAD-1 and Wistar rats. This study has therefore established the baseline disposition characteristics of naltrexone in these strains of rats. PMID:18832863

  17. Disposition of naltrexone after intravenous bolus administration in Wistar rats, low-alcohol-drinking rats and high-alcohol-drinking rats.

    PubMed

    Akala, Emmanuel O; Wang, Hu; Adedoyin, Adedayo

    2008-01-01

    Reports have shown that interspecies differences in the metabolism and pharmacokinetics of naltrexone are a rule rather than exception. However, there is paucity of information on the disposition of naltrexone in selectively bred rat lines that reliably exhibit high and low voluntary alcohol consumption, and are often used to study alcohol-drinking behavior. We have characterized the pharmacokinetic profiles of naltrexone in selectively bred rat lines: high-alcohol-drinking (HAD-1) and low-alcohol-drinking (LAD-1) rats as well as the native Wistar strain. This study was carried out to establish a baseline pharmacokinetic profile of naltrexone in these rats prior to evaluating its pharmacokinetic profile in polymeric controlled-release formulations in our laboratory. The hypothesis is that alcohol-preferring and non-alcohol-preferring lines of rats should differ in the disposition of intravenously administered naltrexone. Naltrexone administration and blood collection were via the jugular vein. In a parallel experiment, naltrexone was administered via the jugular vein, but urine was collected using the Nalgene metabolic cage system. Data were analyzed by a noncompartmental approach. Results show a high clearance that is close to or higher than hepatic blood flow in all groups (Wistar > LAD-1 > HAD-1, but with a statistically significant difference only between Wistar and HAD-1). Volume of distribution (approximately 2.5-3 l/kg) and the half-life (approximately 1 h) were similar. Urinary elimination of naltrexone was small, but also showed differences between the rats: HAD-1 > LAD-1 > Wistar, but with a statistically significant difference only between HAD-1 and Wistar rats. This study has therefore established the baseline disposition characteristics of naltrexone in these strains of rats. PMID:18832863

  18. Impact of streptozotocin on altering normal glucose homeostasis during insulin testing in diabetic rats compared to normoglycemic rats

    PubMed Central

    Qinna, Nidal A; Badwan, Adnan A

    2015-01-01

    Streptozotocin (STZ) is currently the most used diabetogenic agent in testing insulin and new antidiabetic drugs in animals. Due to the toxic and disruptive nature of STZ on organs, apart from pancreas, involved in preserving the body’s normal glucose homeostasis, this study aims to reassess the action of STZ in inducing different glucose response states in diabetic rats while testing insulin. Diabetic Sprague-Dawley rats induced with STZ were classified according to their initial blood glucose levels into stages. The effect of randomizing rats in such a manner was investigated for the severity of interrupting normal liver, pancreas, and kidney functions. Pharmacokinetic and pharmacodynamic actions of subcutaneously injected insulin in diabetic and nondiabetic rats were compared. Interruption of glucose homeostasis by STZ was challenged by single and repeated administrations of injected insulin and oral glucose to diabetic rats. In diabetic rats with high glucose (451–750 mg/dL), noticeable changes were seen in the liver and kidney functions compared to rats with lower basal glucose levels. Increased serum levels of recombinant human insulin were clearly indicated by a significant increase in the calculated maximum serum concentration and area under the concentration–time curve. Reversion of serum glucose levels to normal levels pre- and postinsulin and oral glucose administrations to STZ diabetic rats were found to be variable. In conclusion, diabetic animals were more responsive to insulin than nondiabetic animals. STZ was capable of inducing different levels of normal glucose homeostasis disruption in rats. Both pharmacokinetic and pharmacodynamic actions of insulin were altered when different initial blood glucose levels of STZ diabetic rats were selected for testing. Such findings emphasize the importance of selecting predefined and unified glucose levels when using STZ as a diabetogenic agent in experimental protocols evaluating new antidiabetic agents

  19. Generation of a New Model Rat: Nrf2 Knockout Rats Are Sensitive to Aflatoxin B1 Toxicity.

    PubMed

    Taguchi, Keiko; Takaku, Misaki; Egner, Patricia A; Morita, Masanobu; Kaneko, Takehito; Mashimo, Tomoji; Kensler, Thomas W; Yamamoto, Masayuki

    2016-07-01

    THE TRANSCRIPTION FACTOR NRF2: (NF-E2-related-factor 2) REGULATES A BATTERY OF ANTIOXIDATIVE STRESS-RESPONSE GENES AND DETOXICATION GENES, AND NRF2 KNOCKOUT LINES OF MICE HAVE BEEN CONTRIBUTING CRITICALLY TO THE CLARIFICATION OF ROLES THAT NRF2 PLAYS FOR CELL PROTECTION HOWEVER, THERE ARE APPARENT LIMITATIONS IN USE OF THE MOUSE MODELS FOR INSTANCE, RATS EXHIBIT MORE SUITABLE FEATURES FOR TOXICOLOGICAL OR PHYSIOLOGICAL EXAMINATIONS THAN MICE IN THIS STUDY, WE GENERATED 2 LINES OF NRF2 KNOCKOUT RATS BY USING A GENOME EDITING TECHNOLOGY; 1 LINE HARBORS A 7-BP DELETION Δ7 AND THE OTHER LINE HARBORS A 1-BP INSERTION +1 IN THE NRF2 GENE IN THE LIVERS OF RATS HOMOZYGOUSLY DELETING THE NRF2 GENE, AN ACTIVATOR OF NRF2 SIGNALING, CDDO-IM, COULD NOT INDUCE EXPRESSION OF REPRESENTATIVE NRF2 TARGET GENES TO EXAMINE ALTERED TOXICOLOGICAL RESPONSE, WE TREATED THE NRF2 KNOCKOUT RATS WITH AFLATOXIN B1 AFB1, A CARCINOGENIC MYCOTOXIN THAT ELICITS GENE MUTATIONS THROUGH BINDING OF ITS METABOLITES TO DNA AND FOR WHICH THE RAT HAS BEEN PROPOSED AS A REASONABLE SURROGATE FOR HUMAN TOXICITY INDEED, IN THE NRF2 KNOCKOUT RAT LIVERS THE ENZYMES OF THE AFB1 DETOXICATION PATHWAY WERE SIGNIFICANTLY DOWNREGULATED SINGLE DOSE ADMINISTRATION OF AFB1 INCREASED HEPATOTOXICITY AND BINDING OF AFB1-N7-GUANINE TO HEPATIC DNA IN NRF2 KNOCKOUT RATS COMPARED WITH WILD-TYPE NRF2 KNOCKOUT RATS REPEATEDLY TREATED WITH AFB1 WERE PRONE TO LETHALITY AND CDDO-IM WAS NO LONGER PROTECTIVE THESE RESULTS DEMONSTRATE THAT NRF2 KNOCKOUT RATS ARE QUITE SENSITIVE TO AFB1 TOXICITIES AND THIS RAT GENOTYPE EMERGES AS A NEW MODEL ANIMAL IN TOXICOLOGY. PMID:27071940

  20. High-fat diet-induced obesity Rat model: a comparison between Wistar and Sprague-Dawley Rat

    PubMed Central

    Marques, Cláudia; Meireles, Manuela; Norberto, Sónia; Leite, Joana; Freitas, Joana; Pestana, Diogo; Faria, Ana; Calhau, Conceição

    2016-01-01

    ABSTRACT In the past decades, obesity and associated metabolic complications have reached epidemic proportions. For the study of these pathologies, a number of animal models have been developed. However, a direct comparison between Wistar and Sprague-Dawley (SD) Rat as models of high-fat (HF) diet-induced obesity has not been adequately evaluated so far. Wistar and SD rats were assigned for 2 experimental groups for 17 weeks: standard (St) and high-fat (HF) diet groups. To assess some of the features of the metabolic syndrome, oral glucose tolerance tests, systolic blood pressure measurements and blood biochemical analysis were performed throughout the study. The gut microbiota composition of the animals of each group was evaluated at the end of the study by real-time PCR. HF diet increased weight gain, body fat mass, mesenteric adipocyte's size, adiponectin and leptin plasma levels and decreased oral glucose tolerance in both Wistar and SD rats. However, the majority of these effects were more pronounced or earlier detected in Wistar rats. The gut microbiota of SD rats was less abundant in Bacteroides and Prevotella but richer in Bifidobacterium and Lactobacillus comparatively to the gut microbiota of Wistar rats. Nevertheless, the modulation of the gut microbiota by HF diet was similar in both strains, except for Clostridium leptum that was only reduced in Wistar rats fed with HF diet. In conclusion, both Wistar and SD Rat can be used as models of HF diet-induced obesity although the metabolic effects caused by HF diet seemed to be more pronounced in Wistar Rat. Differences in the gut microbial ecology may account for the worsened metabolic scenario observed in Wistar Rat. PMID:27144092

  1. The Effects of Spaceflight on the Rat Circadian Timing System

    NASA Technical Reports Server (NTRS)

    Fuller, Charles A.; Murakami, Dean M.; Hoban-Higgins, Tana M.; Fuller, Patrick M.; Robinson, Edward L.; Tang, I.-Hsiung

    2003-01-01

    Two fundamental environmental influences that have shaped the evolution of life on Earth are gravity and the cyclic changes occurring over the 24-hour day. Light levels, temperature, and humidity fluctuate over the course of a day, and organisms have adapted to cope with these variations. The primary adaptation has been the evolution of a biological timing system. Previous studies have suggested that this system, named the circadian (circa - about; dies - a day) timing system (CTS), may be sensitive to changes in gravity. The NASA Neurolab spaceflight provided a unique opportunity to evaluate the effects of microgravity on the mammalian CTS. Our experiment tested the hypotheses that microgravity would affect the period, phasing, and light sensitivity of the CTS. Twenty-four Fisher 344 rats were exposed to 16 days of microgravity on the Neurolab STS-90 mission, and 24 Fisher 344 rats were also studied on Earth as one-G controls. Rats were equipped with biotelemetry transmitters to record body temperature (T(sub b)) and heart rate (HR) continuously while the rats moved freely. In each group, 18 rats were exposed to a 24-hour light-dark (LD 12:12) cycle, and six rats were exposed to constant dim red-light (LL). The ability of light to induce a neuronal activity marker (c-fos) in the circadian pacemaker of the brain, the suprachiasmatic nucleus (SCN), was examined in rats studied on flight days two (FD2) and 14 (FD14), and postflight days two (R+1) and 14 (R+13). The flight rats in LD remained synchronized with the LD cycle. However, their T(sub b), rhythm was markedly phase-delayed relative to the LD cycle. The LD flight rats also had a decreased T(sub b) and a change in the waveform of the T(sub b) rhythm compared to controls. Rats in LL exhibited free-running rhythms of T(sub b), and HR; however, the periods were longer in microgravity. Circadian period returned to preflight values after landing. The internal phase angle between rhythms was different in flight than

  2. Intermittent hypoxia maintains glycemia in streptozotocin-induced diabetic rats.

    PubMed

    Chen, Xiaofei; Zhao, Tong; Huang, Xin; Wu, Liying; Wu, Kuiwu; Fan, Ming; Zhu, Lingling

    2016-05-01

    Increasing studies have shown protective effects of intermittent hypoxia on brain injury and heart ischemia. However, the effect of intermittent hypoxia on blood glucose metabolism, especially in diabetic conditions, is rarely observed. The aim of this study was to investigate whether intermittent hypoxia influences blood glucose metabolism in type 1 diabetic rats. Streptozotocin-induced diabetic adult rats and age-matched control rats were treated with intermittent hypoxia (at an altitude of 3 km, 4 h per day for 3 weeks) or normoxia as control. Fasting blood glucose, body weight, plasma fructosamine, plasma insulin, homeostasis model assessment of insulin resistance (HOMA-IR), pancreas β-cell mass, and hepatic and soleus glycogen were measured. Compared with diabetic rats before treatment, the level of fasting blood glucose in diabetic rats after normoxic treatment was increased (19.88 ± 5.69 mmol/L vs. 14.79 ± 5.84 mmol/L, p < 0.05), while it was not different in diabetic rats after hypoxic treatment (13.14 ± 5.77 mmol/L vs. 14.79 ± 5.84 mmol/L, p > 0.05). Meanwhile, fasting blood glucose in diabetic rats after hypoxic treatment was also lower than that in diabetic rats after normoxic treatment (13.14 ± 5.77 mmol/L vs. 19.88 ± 5.69 mmol/L, p<0.05). Plasma fructosamine in diabetic rats receiving intermittent hypoxia was significantly lower than that in diabetic rats receiving normoxia (1.28 ± 0.11 vs. 1.39 ± 0.11, p < 0.05), while there were no significant changes in body weight, plasma insulin and β-cell mass. HOMA-IR in diabetic rats after hypoxic treatment was also lower compared with diabetic rats after normoxic treatment (3.48 ± 0.48 vs. 3.86 ± 0.42, p < 0.05). Moreover, intermittent hypoxia showed effect on the increase of soleus glycogen but not hepatic glycogen. We conclude that intermittent hypoxia maintains glycemia in streptozotocin-induced diabetic rats and its regulation on muscular

  3. Activation of factor X by rat hepatocytes

    SciTech Connect

    Willingham, A.K.; Matschiner, J.T.

    1986-05-01

    Synthesis and secretion of blood coagulation factor X was studied in hepatocytes prepared by perfusion of rat livers with collagenase. Hepatocytes were incubated in the presence of vitamin K and /sup 3/H-leucine for up to 4h at 37/sup 0/C. Factor X was isolated from the incubation medium by immunochemical techniques and analyzed by SDS-PAGE. The recovered /sup 3/H-labeled proteins migrated, after reduction of disulfides, as two polypeptide chains with apparent molecular weights (M/sub r/) of approximately 42,000 and 22,000 representing the heavy and light chains of factor X respectively. The apparent M/sub r/ of the heavy chain was about 10,000 daltons lighter than seen with the heavy chain of factor X isolated from rat plasma and was more characteristic of the heavy chain of factor Xa. When the levels of factor X secreted by hepatocytes were determined by clotting assays, activity was present as factor Xa. Also, when purified plasma factor X was added to incubations of hepatocytes (>95% parenchymal cells) the added factor X was rapidly converted to factor Xa. Plasma membranes prepared from isolated hepatocytes or from liver homogenates contained an enzyme that converted factor X to factor Xa in a calcium dependent reaction. The physiological significance of a factor X activating enzyme on hepatocyte plasma membranes is not clear.

  4. Neuroendocrine effects of perfluorooctane sulfonate in rats.

    PubMed Central

    Austin, Maureen E; Kasturi, Badrinarayanan S; Barber, Matthew; Kannan, Kurunthachalam; MohanKumar, Puliyur S; MohanKumar, Sheba M J

    2003-01-01

    Perfluorooctane sulfonate (PFOS) is a degradation product of sulfonyl-based fluorochemicals that are used extensively in industrial and household applications. Humans and wildlife are exposed to this class of compounds from several sources. Toxicity tests in rodents have raised concerns about potential developmental, reproductive, and systemic effects of PFOS. However, the effect of PFOS on the neuroendocrine system has not been investigated thus far. In this study, adult female rats were injected intraperitoneally with 0, 1, or 10 mg PFOS/kg body weight (BW) for 2 weeks. Food and water intake, BW, and estrous cycles were monitored daily. At the end of treatment, PFOS levels in tissues were measured by high-performance liquid chromatography (HPLC) interfaced with electrospray mass spectrometry. Changes in brain monoamines were measured by HPLC with electrochemical detection, and serum corticosterone and leptin were monitored using radioimmunoassay. Treatment with PFOS produced a dose-dependent accumulation of this chemical in various body tissues, including the brain. PFOS exposure decreased food intake and BW in a dose-dependent manner. Treatment with PFOS affected estrous cyclicity and increased serum corticosterone levels while decreasing serum leptin concentrations. PFOS treatment also increased norepinephrine concentrations in the paraventricular nucleus of the hypothalamus. These results indicate that exposure to PFOS can affect the neuroendocrine system in rats. PMID:12948888

  5. Heterogeneous expression of transketolase in rat brain.

    PubMed

    Calingasan, N Y; Sheu, K F; Baker, H; Jung, E H; Paoletti, F; Gibson, G E

    1995-03-01

    Transketolase (TK; EC 2.2.1.1) is a key pentose phosphate shunt enzyme that plays an important role in the production of reducing equivalents and pentose sugars. TK activity declines in the brains of patients with Alzheimer's disease or Wernicke-Korsakoff syndrome, as well as in thiamine-deficient rats. Understanding the role of TK in the pathophysiology of these neurodegenerative conditions requires knowledge of its regional, cellular, and subcellular distribution within the brain. The current study employed in situ hybridization and immunocytochemistry to examine the distribution of TK mRNA and its encoded protein in adult rat brain. TK mRNA and protein were widely distributed throughout the brain. However, they were enriched in selective perikarya in the piriform cortex, nucleus of the diagonal band, red nucleus, dorsal raphe, pontine nucleus, locus coeruleus, trapezoid, inferior olive, and several cranial nerve nuclei. Lower expression of TK mRNA and protein occurred in layer V of cortex, olfactory tubercle, ventral pallidum, medial septal nucleus, hippocampus, thalamic and hypothalamic nuclei, mammillary body, central gray, and the substantia nigra. TK immunoreactivity also occurred in the nuclei of ubiquitously distributed glial cells, as well as ependymal cells. The heterogeneous distribution of TK may reflect a variety of metabolic activities among different brain regions but does not provide a simple molecular explanation for selective cell death in either thiamine deficiency or other conditions where TK is reduced. PMID:7861132

  6. Deoxyribonuclease I in mammalian tissues. [Rats

    SciTech Connect

    Lacks, S.A.

    1981-03-25

    Enzymes of the DNase I class, similar to bovine pancreatic DNase I with respect to molecular weight and ionic and pH requirements, were found in various tissues of the rat. Their analysis was facilitated by a method for detection of nucleases in crude extracts after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and subsequent renaturation of the enzymes. High levels of DNase I were found in digestive tissues, such as the parotid and submaxillary salivary glands and the lining of the small intestine. Appreciable levels were present in the lymph node, kidney, heart, prostate gland, and seminal vesicle. No activity was found in pancreatic extracts. However, under some conditions, tissues rich in proteases gave poor recovery of DNase I. Fourteen other tissues showed little or no DNase I. Inhibition of various DNase I enzymes by rabbit muscle actin was examined both in gels and in solution. Actin inhibited the bovine parotid DNase I as well as the bovine pancreatic enzyme, but actin did not inhibit any of the DNase I enzymes of the rat. This species specificity of actin inhibition makes it unlikely that the very strong association between monomeric actin and bovine DNase I is of general significance for cellular function.

  7. Mechanical responses of rat vibrissae to airflow.

    PubMed

    Yu, Yan S W; Graff, Matthew M; Hartmann, Mitra J Z

    2016-04-01

    The survival of many animals depends in part on their ability to sense the flow of the surrounding fluid medium. To date, however, little is known about how terrestrial mammals sense airflow direction or speed. The present work analyzes the mechanical response of isolated rat macrovibrissae (whiskers) to airflow to assess their viability as flow sensors. Results show that the whisker bends primarily in the direction of airflow and vibrates around a new average position at frequencies related to its resonant modes. The bending direction is not affected by airflow speed or by geometric properties of the whisker. In contrast, the bending magnitude increases strongly with airflow speed and with the ratio of the whisker's arc length to base diameter. To a much smaller degree, the bending magnitude also varies with the orientation of the whisker's intrinsic curvature relative to the direction of airflow. These results are used to predict the mechanical responses of vibrissae to airflow across the entire array, and to show that the rat could actively adjust the airflow data that the vibrissae acquire by changing the orientation of its whiskers. We suggest that, like the whiskers of pinnipeds, the macrovibrissae of terrestrial mammals are multimodal sensors - able to sense both airflow and touch - and that they may play a particularly important role in anemotaxis. PMID:27030774

  8. Characterization of rat cecum cellulolytic bacteria.

    PubMed Central

    Montgomery, L; Macy, J M

    1982-01-01

    Cellulose-degrading bacteria previously isolated from the ceca of rats have been characterized and identified. The most commonly isolated type was rods identified as Bacteroides succinogenes. These bacteria fermented only cellulose (e.g., pebble-milled Whatman no. 1 filter paper), cellobiose, and in 43 of 47 strains, glucose, with succinic and acetic acids as the major products. The only organic growth factors found to be required by selected strains were p-aminobenzoic acid, cyanocobalamine, thiamine, and a straight-chain and a branched-chain volatile fatty acid. These vitamin requirements differ from those of rumen strains of B. succinogenes, indicating the rat strains may form a distinct subgroup within the species. The mole percent guanine plus cytosine was 45%, a value lower than those (48 to 51%) found for three rumen strains of B. succinogenes included in this study. Cellulolytic cocci were isolated less frequently than the rods and were identified as Rumminococcus flavefaciens. Most strains fermented only cellulose and cellobiose, and their major fermentation products were also succinic and acetic acids. Their required growth factors were not identified but were supplied by rumen fluid. Images PMID:7159086

  9. TEMPORAL ALTERNATION IN THE WHITE RAT.

    PubMed

    KEEHN, J D

    1965-05-01

    Four white rats were reinforced after 15 then 45 then 15 then 135 (or 5) responses to a bar under a single exteroceptive stimulus condition. Three came to make long pauses before the longest ratio in the schedule but not before any of the others. Four other rats were reinforced after alternate response chains each made on two bars. The first chain was FR5FR5 for all subjects, the second FR5FR40 for two, and FR40FR5 and FR20FR5 for one subject each. Subjects reinforced on schedule mix (chain FR5FR5 chain FR5FR40) both paused longer after the first than after the second chain relatively early in training. Later, the subject reinforced on mix (chain FR5FR5 chain FR40FR5) also paused longer after the first chain, but pauses of the fourth subject were equally short after both chains. When the ratios in the second chain were reversed the two subjects now reinforced on mix (chain FR5FR5 chain FR40FR5) paused much longer after the first chain, but the other two paused only slightly longer after the first than after the second chain. PMID:14302748

  10. Neurobehavioral teratogenic effects of thalidomide in rats.

    PubMed

    Vorhees, C V; Weisenburger, W P; Minck, D R

    2001-01-01

    Thalidomide-induced embryopathy has been known for four decades, however, the drug has been reintroduced for human use in a number of countries, including the United States. In utero thalidomide exposure in humans is associated with central nervous system (CNS) effects in addition to the well-known limb, ear and other malformations. Despite knowledge of these CNS effects, not a single experimental study could be found that examined thalidomide for possible developmental neurobehavioral effects. In the present experiment, gravid Sprague-Dawley rats were treated with either thalidomide (100 mg/kg by gavage) or vehicle (propylene glycol) on embryonic days E7-18 and allowed to deliver and raise their own offspring. The offspring were evaluated in a series of neurobehavioral tests (reflexes, locomotor activity, startle reactivity and learning in the Morris and Cincinnati water mazes). There was a small reduction in maternal weight among thalidomide-treated dams during midgestation. Thalidomide offspring showed increased preweaning mortality and male-specific, late onset reduction in growth that persisted until the end of the study. Male thalidomide offspring showed significant increases in errors and latency in the multiple-T Cincinnati water maze. Although rats are refractory to thalidomide-induced teratogenesis, the present results suggest that thalidomide selectively impairs offspring survival and growth and at least one type of learning among male offspring. PMID:11418267

  11. Isolation and Cryopreservation of Neonatal Rat Cardiomyocytes

    PubMed Central

    Vandergriff, Adam C.; Hensley, Michael Taylor; Cheng, Ke

    2016-01-01

    Cell culture has become increasingly important in cardiac research, but due to the limited proliferation of cardiomyocytes, culturing cardiomyocytes is difficult and time consuming. The most commonly used cells are neonatal rat cardiomyocytes (NRCMs), which require isolation every time cells are needed. The birth of the rats can be unpredictable. Cryopreservation is proposed to allow for cells to be stored until needed, yet freezing/thawing methods for primary cardiomyocytes are challenging due to the sensitivity of the cells. Using the proper cryoprotectant, dimethyl sulfoxide (DMSO), cryopreservation was achieved. By slowly extracting the DMSO while thawing the cells, cultures were obtained with viable NRCMs. NRCM phenotype was verified using immunocytochemistry staining for α-sarcomeric actinin. In addition, cells also showed spontaneous contraction after several days in culture. Cell viability after thawing was acceptable at 40–60%. In spite of this, the methods outlined allow one to easily cryopreserve and thaw NRCMs. This gives researchers a greater amount of flexibility in planning experiments as well as reducing the use of animals. PMID:25938862

  12. Rat injury model of docetaxel extravasation

    PubMed Central

    ZHU, JING-JING; FU, JIAN-FEI; YANG, JIAO; HU, BING; ZHANG, HUI; YU, JIAN-HUA

    2014-01-01

    Docetaxel is a novel type of chemotherapy drug that actively treats a number of malignant tumors. The aim of the present study was to explore the severity and natural course of tissue damage induced by docetaxel extravasation and to confirm the vesicant potential of docetaxel. Rats were selected for the establishment of the ulcer model. Different volumes and concentrations were explored to induce the skin ulcer and to confirm the optimum rational injection model. The natural course of tissue injury and pathological changes produced by docetaxel extravasation were observed by comparing to vinorelbine extravasation. A 0.4 ml volume and a 6 mg/ml concentration were the optimum rational injection model for the induction of the skin ulcer. The docetaxel extravasation induced local tissue necrosis, followed by granuloma formation and hyperpigmentation or scar formation. The severity of the injury depended on the concentration of the extravasation used in the rat model. The injury occurred on the first day following extravasation and lasted 4–6 weeks. The damage from docetaxel was weaker than vinorelbine in association with the depth and extension of necrosis. In conclusion, docetaxel extravasation can induce tissue necrosis. However, the severity of necrosis was weaker than that of vinorelbine. Docetaxel has superficial vesicant properties. PMID:25054005

  13. Glucose metabolism in rat retinal pigment epithelium.

    PubMed

    Coffe, Víctor; Carbajal, Raymundo C; Salceda, Rocío

    2006-01-01

    The retinal pigment epithelium (RPE) is the major transport pathway for exchange of metabolites and ions between choroidal blood supply and the neural retina. To gain insight into the mechanisms controlling glucose metabolism in RPE and its possible relationship to retinopathy, we studied the influence of different glucose concentrations on glycogen and lactate levels and CO(2) production in RPE from normal and streptozotocin-treated diabetic rats. Incubation of normal RPE in the absence of glucose caused a decrease in lactate production and glycogen content. In normal RPE, increasing glucose concentrations from 5.6 mM to 30 mM caused a four-fold increase in glucose accumulation and CO(2) yield, as well as reduction in lactate and glycogen production. In RPE from diabetic rats glucose accumulation did not increase in the presence of high glucose substrate, but it showed a four- and a seven-fold increase in CO(2) production through the mitochondrial and pentose phosphate pathways, respectively. We found high glycogen levels in RPE which can be used as an energy reserve for RPE itself and/or neural retina. Findings further show that the RPE possesses a high oxidative capacity. The large increase in glucose shunting to the pentose phosphate pathway in diabetic retina exposed to high glucose suggests a need for reducing capacity, consistent with increased oxidative stress. PMID:16475003

  14. Calretinin Neurons in the Rat Suprachiasmatic Nucleus.

    PubMed

    Moore, Robert Y

    2016-08-01

    The hypothalamic suprachiasmatic nucleus (SCN), a circadian pacemaker, is present in all mammalian brains. It has a complex organization of peptide-containing neurons that is similar among species, but calcium-binding proteins are expressed variably. Neurons containing calretinin have been described in the SCN in a number of species but not with association to circadian function. The objective of the present study is to characterize a calretinin neuron (CAR) group in the rat anterior hypothalamus anatomically and functionally with a detailed description of its location and a quantitative analysis of neuronal calretinin immunoreactivity at 3 times of day, 0600, 1400, and 1900 h, from animals in either light-dark or constant dark conditions. CAR neurons occupy a region in the dorsal and lateral SCN with a circadian rhythm in CAR immunoreactivity with a peak at 0600 h and a rhythm in cytoplasmic CAR distribution with a peak at 1400 h. CAR neurons should be viewed as an anatomical and functional component of the rat SCN that expands the definition from observations with cell stains. CAR neurons are likely to modulate temporal regulation of calcium in synaptic transmission. PMID:27330050

  15. Focal embolic cerebral ischemia in the rat

    PubMed Central

    Zhang, Li; Zhang, Rui Lan; Jiang, Quan; Ding, Guangliang; Chopp, Michael; Zhang, Zheng Gang

    2015-01-01

    Animal models of focal cerebral ischemia are well accepted for investigating the pathogenesis and potential treatment strategies for human stroke. Occlusion of the middle cerebral artery (MCA) with an endovascular filament is a widely used model to induce focal cerebral ischemia. However, this model is not amenable to thrombolytic therapies. As thrombolysis with recombinant tissue plasminogen activator (rtPA) is a standard of care within 4.5 hours of human stroke onset, suitable animal models that mimic cellular and molecular mechanisms of thrombosis and thrombolysis of stroke are required. By occluding the MCA with a fibrin-rich allogeneic clot, we have developed an embolic model of MCA occlusion in the rat, which recapitulates the key components of thrombotic development and of thrombolytic therapy of rtPA observed from human ischemic stroke. The surgical procedures of our model can be typically completed within approximately 30 min and are highly adaptable to other strains of rats as well as mice for both genders. Thus, this model provides a powerful tool for translational stroke research. PMID:25741989

  16. Rapid whisker movements in sleeping newborn rats.

    PubMed

    Tiriac, Alexandre; Uitermarkt, Brandt D; Fanning, Alexander S; Sokoloff, Greta; Blumberg, Mark S

    2012-11-01

    Spontaneous activity in the sensory periphery drives infant brain activity and is thought to contribute to the formation of retinotopic and somatotopic maps. In infant rats during active (or REM) sleep, brainstem-generated spontaneous activity triggers hundreds of thousands of skeletal muscle twitches each day; sensory feedback from the resulting limb movements is a primary activator of forebrain activity. The rodent whisker system, with its precise isomorphic mapping of individual whiskers to discrete brain areas, has been a key contributor to our understanding of somatotopic maps and developmental plasticity. But although whisker movements are controlled by dedicated skeletal muscles, spontaneous whisker activity has not been entertained as a contributing factor to the development of this system. Here we report in 3- to 6-day-old rats that whiskers twitch rapidly and asynchronously during active sleep; furthermore, neurons in whisker thalamus exhibit bursts of activity that are tightly associated with twitches but occur infrequently during waking. Finally, we observed barrel-specific cortical activity during periods of twitching. This is the first report of self-generated, sleep-related twitches in the developing whisker system, a sensorimotor system that is unique for the precision with which it can be experimentally manipulated. The discovery of whisker twitching will allow us to attain a better understanding of the contributions of peripheral sensory activity to somatosensory integration and plasticity in the developing nervous system. PMID:23084988

  17. Nuclear microscopy of rat colon epithelial cells

    NASA Astrophysics Data System (ADS)

    Ren, M.; Rajendran, Reshmi; Ng, Mary; Udalagama, Chammika; Rodrigues, Anna E.; Watt, Frank; Jenner, Andrew Michael

    2011-10-01

    Using Nuclear microscopy, we have investigated iron distributions in the colons of Sprague Dawley rats, in order to elucidate heme uptake. Four groups of five Sprague Dawley rats (mean weight 180 g) were fed different purified diets containing either heme diet (2.5% w/w hemoglobin), high fat diet (HFD) (18% w/w fat, 1% w/w cholesterol), 'western' diet (combination of hemoglobin 2.5% and 18% fat, 1% cholesterol) or control diet (7% w/w fat). After 4 weeks, animals were sacrificed by exsanguination after anaesthesia. Thin sections of frozen colon tissue were taken, freeze dried and scanned using nuclear microscopy utilising the techniques PIXE, RBS and STIM. The new data acquisition system (IonDaq) developed in CIBA was used to obtain high resolution images and line scans were used to map the iron distributions across the colon boundaries. The nuclear microscope results indicate that when HFD is given in addition to heme, the iron content of the epithelial cells that line the colon decreases, and the zinc in the smooth muscle wall increases. This implies that the level of heme and fat in diet has an important role in colon health, possibly by influencing epithelial cells directly or changing luminal composition such as bacterial flora or levels of metabolites and cytotoxins.

  18. [Sucrose reward promotes rats' motivation for cocaine].

    PubMed

    Li, Yan-Qing; LE, Qiu-Min; Yu, Xiang-Chen; Ma, Lan; Wang, Fei-Fei

    2016-06-25

    Caloric diet, such as fat and sugar intake, has rewarding effects, and has been indicated to affect the responses to addictive substances in animal experiments. However, the possible association between sucrose reward and the motivation for addictive drugs remains to be elucidated. Thus, we carried out behavioral tests after sucrose self-administration training to determine the effects of sucrose experience on rats' motivation for cocaine, locomotor sensitivity to cocaine, basal locomotor activity, anxiety level, and associative learning ability. The sucrose-experienced (sucrose) group exhibited higher lever press, cocaine infusion and break point, as well as upshift of cocaine dose-response curve in cocaine self-administration test, as compared with the control (chow) group. Additionally, despite similar locomotor activity in open field test and comparable score in cocaine-induced conditioned place preference, the sucrose group showed higher cocaine-induced locomotor sensitivity as compared with the chow group. The anxiety level and the performance in vocal-cue induced fear memory were similar between these two groups in elevated plus maze and fear conditioning tests, respectively. Taken together, our work indicates that sucrose experience promotes the rats' motivation for cocaine. PMID:27350195

  19. Ideal Experimental Rat Models for Liver Diseases.

    PubMed

    Lee, Sang Woo; Kim, Sung Hoon; Min, Seon Ok; Kim, Kyung Sik

    2011-05-01

    There are many limitations for conducting liver disease research in human beings due to the high cost and potential ethical issues. For this reason, conducting a study that is difficult to perform in humans using appropriate animal models, can be beneficial in ascertaining the pathological physiology, and in developing new treatment modalities. However, it is difficult to determine the appropriate animal model which is suitable for research purposes, since every patient has different and diverse clinical symptoms, adverse reactions, and complications due to the pathological physiology. Also, it is not easy to reproduce identically various clinical situations in animal models. Recently, the Guide for the Care and Use of Laboratory Animals has tightened up the regulations, and therefore it is advisable to select the appropriate animals and decide upon the appropriate quantities through scientific and systemic considerations before conducting animal testing. Therefore, in this review article the authors examined various white rat animal testing models and determined the appropriate usable rat model, and the pros and cons of its application in liver disease research. The authors believe that this review will be beneficial in selecting proper laboratory animals for research purposes. PMID:26421020

  20. Studies of aluminum in rat brain

    SciTech Connect

    Lipman, J.J.; Brill, A.B.; Som, P.; Jones, K.W.; Colowick, S.; Cholewa, M.

    1985-01-01

    The effects of high aluminum concentrations in rat brains were studied using /sup 14/C autoradiography to measure the uptake of /sup 14/C 2-deoxy-D-glucose (/sup 14/C-2DG) and microbeam proton-induced x-ray emission (microPIXE) with a 20-..mu..m resolution to measure concentrations of magnesium, aluminum, potassium, and calcium. The aluminum was introduced intracisternally in the form of aluminum tartrate (Al-T) while control animals were given sodium tartrate (Na-T). The /sup 14/C was administered intravenously. The animals receiving Al-T developed seizure disorders and had pathological changes that included cerebral cortical atrophy. The results showed that there was a decreased uptake of /sup 14/C-2DG in cortical regions in which increased aluminum levels were measured, i.e., there is a correlation between the aluminum in the rat brain and decreased brain glucose metabolism. A minimum detection limit of about 16 ppM (mass fraction) or 3 x 10/sup 9/ Al atoms was obtained for Al under the conditions employed. 14 refs., 4 figs., 1 tab.

  1. Rat splanchnic net oxygen consumption, energy implications.

    PubMed Central

    Casado, J; Fernández-López, J A; Esteve, M; Rafecas, I; Argilés, J M; Alemany, M

    1990-01-01

    1. The blood flow, PO2, pH and PCO2 have been estimated in portal and suprahepatic veins as well as in hepatic artery of fed and overnight starved rats given an oral glucose load. From these data the net intestinal, hepatic and splanchnic balances for oxygen and bicarbonate were calculated. The oxygen consumption of the intact animal has also been measured under comparable conditions. 2. The direct utilization of oxygen balances as energy equivalents when establishing the contribution of energy metabolism of liver and intestine to the overall energy expenses of the rat, has been found to be incorrect, since it incorporates the intrinsic error of interorgan proton transfer through bicarbonate. Liver and intestine produced high net bicarbonate balances in all situations tested, implying the elimination (by means of oxidative pathways, i.e. consuming additional oxygen) of high amounts of H+ generated with bicarbonate. The equivalence in energy output of the oxygen balances was then corrected for bicarbonate production to 11-54% lower values. 3. Intestine and liver consume a high proportion of available oxygen, about one-half in basal (fed or starved) conditions and about one-third after gavage, the intestine consumption being about 15% in all situations tested and the liver decreasing its oxygen consumption with gavage. PMID:2129230

  2. Kavalactone metabolism in rat liver microsomes.

    PubMed

    Fu, Shuang; Rowe, Anthony; Ramzan, Iqbal

    2012-07-01

    The specific CYP enzymes involved in kavalactone (KLT) metabolism and their kinetics have not been fully examined. This study used rat liver microsomes (RLM) to determine kavain (KA), methysticin (MTS) and desmethoxyyangonin (DMY) enzyme kinetic parameters, to elucidate the major CYP450 isoforms involved in KLT metabolism and to examine gender differences in KLT metabolism. Formation of the major KLT metabolites was first-order, consistent with classic enzyme kinetics. In both male and female RLM, clotrimazole (CLO) was the most potent inhibitor of KA and MTS metabolism. This suggests CYP3A1/3A23 (females) and CYP3A2 (males) are the main isoenzymes involved in the metabolism of these KLTs in rats, while the roles of CYP1A2, -2 C6, -2 C9, -2E1 and -3A4 are limited. Desmethoxyyangonin metabolism was equally inhibited by cimetidine (CIM) and CLO in females, and CIM and nortriptyline in males. This implies that DMY metabolism involves CYP2C6 and CYP2C11 in males, and CPY2C12 in females. CYP3A1/3A23 may also be involved in females. PMID:22807255

  3. Interactions between respiratory oscillators in adult rats

    PubMed Central

    Huckstepp, Robert TR; Henderson, Lauren E; Cardoza, Kathryn P; Feldman, Jack L

    2016-01-01

    Breathing in mammals is hypothesized to result from the interaction of two distinct oscillators: the preBötzinger Complex (preBötC) driving inspiration and the lateral parafacial region (pFL) driving active expiration. To understand the interactions between these oscillators, we independently altered their excitability in spontaneously breathing vagotomized urethane-anesthetized adult rats. Hyperpolarizing preBötC neurons decreased inspiratory activity and initiated active expiration, ultimately progressing to apnea, i.e., cessation of both inspiration and active expiration. Depolarizing pFL neurons produced active expiration at rest, but not when inspiratory activity was suppressed by hyperpolarizing preBötC neurons. We conclude that in anesthetized adult rats active expiration is driven by the pFL but requires an additional form of network excitation, i.e., ongoing rhythmic preBötC activity sufficient to drive inspiratory motor output or increased chemosensory drive. The organization of this coupled oscillator system, which is essential for life, may have implications for other neural networks that contain multiple rhythm/pattern generators. DOI: http://dx.doi.org/10.7554/eLife.14203.001 PMID:27300271

  4. Preparation of Highly Coupled Rat Heart Mitochondria

    PubMed Central

    Gostimskaya, Irina; Galkin, Alexander

    2010-01-01

    The function of mitochondria in generation of cellular ATP in the process of oxidative phosphorylation is widely recognised. During the past decades there have been significant advances in our understanding of the functions of mitochondria other than the generation of energy. These include their role in apoptosis, acting as signalling organelles, mammalian development and ageing as well as their contribution to the coordination between cell metabolism and cell proliferation. Our understanding of biological processes modulated by mitochondria is based on robust methods for isolation and handling of intact mitochondria from tissues of the laboratory animals. Mitochondria from rat heart is one of the most common preparations for past and current studies of cellular metabolism including studies on knock-out animals. Here we describe a detailed rapid method for isolation of intact mitochondria with a high degree of coupling. Such preparation of rat heart mitochondria is an excellent object for functional and structural research on cellular bioenergetics, transport of biomolecules, proteomic studies and analysis of mitochondrial DNA, proteins and lipids. PMID:20972393

  5. Pharmacokinetics and biodegradation of chitosan in rats

    NASA Astrophysics Data System (ADS)

    Li, Hui; Jiang, Zhiwen; Han, Baoqin; Niu, Shuyi; Dong, Wen; Liu, Wanshun

    2015-10-01

    Chitosan, an excellent biomedical material, has received a widespread in vivo application. In contrast, its metabolism and distribution once being implanted were less documented. In this study, the pharmacokinetics and biodegradation of fluorescein isothiocyanate (FITC) labeled and muscle implantation administrated chitosan in rats were investigated with fluorescence spectrophotometry, histological assay and gel chromatography. After implantation, chitosan was degraded gradually during its distribution to diverse organs. Among the tested organs, liver and kidney were found to be the first two highest in chitosan content, which was followed by heart, brain and spleen. Urinary excretion was believed to be the major pathway of chitosan elimination, yet 80% of chitosan administered to rats was not trackable in their urine. This indicated that the majority of chitosan was degraded in tissues. In average, the molecular weight of the degradation products of chitosan in diverse organs and urine was found to be <65 kDa. This further confirmed the in vivo degradation of chitosan. Our findings provided new evidences for the intensive and safe application of chitosan as a biomedical material.

  6. Ozone inhalation modifies the rat liver proteome☆

    PubMed Central

    Theis, Whitney S.; Andringa, Kelly K.; Millender-Swain, Telisha; Dickinson, Dale A.; Postlethwait, Edward M.; Bailey, Shannon M.

    2013-01-01

    Ozone (O3) is a serious public health concern. Recent findings indicate that the damaging health effects of O3 extend to multiple systemic organ systems. Herein, we hypothesize that O3 inhalation will cause downstream alterations to the liver. To test this, male Sprague-Dawley rats were exposed to 0.5 ppm O3 for 8 h/day for 5 days. Plasma liver enzyme measurements showed that 5 day O3 exposure did not cause liver cell death. Proteomic and mass spectrometry analysis identified 10 proteins in the liver that were significantly altered in abundance following short-term O3 exposure and these included several stress responsive proteins. Glucose-regulated protein 78 and protein disulfide isomerase increased, whereas glutathione S-transferase M1 was significantly decreased by O3 inhalation. In contrast, no significant changes were detected for the stress response protein heme oxygenase-1 or cytochrome P450 2E1 and 2B in liver of O3 exposed rats compared to controls. In summary, these results show that an environmentally-relevant exposure to inhaled O3 can alter the expression of select proteins in the liver. We propose that O3 inhalation may represent an important unrecognized factor that can modulate hepatic metabolic functions. PMID:25544660

  7. Neuroendocrine effects of perfluorooctane sulfonate in rats.

    PubMed

    Austin, Maureen E; Kasturi, Badrinarayanan S; Barber, Matthew; Kannan, Kurunthachalam; MohanKumar, Puliyur S; MohanKumar, Sheba M J

    2003-09-01

    Perfluorooctane sulfonate (PFOS) is a degradation product of sulfonyl-based fluorochemicals that are used extensively in industrial and household applications. Humans and wildlife are exposed to this class of compounds from several sources. Toxicity tests in rodents have raised concerns about potential developmental, reproductive, and systemic effects of PFOS. However, the effect of PFOS on the neuroendocrine system has not been investigated thus far. In this study, adult female rats were injected intraperitoneally with 0, 1, or 10 mg PFOS/kg body weight (BW) for 2 weeks. Food and water intake, BW, and estrous cycles were monitored daily. At the end of treatment, PFOS levels in tissues were measured by high-performance liquid chromatography (HPLC) interfaced with electrospray mass spectrometry. Changes in brain monoamines were measured by HPLC with electrochemical detection, and serum corticosterone and leptin were monitored using radioimmunoassay. Treatment with PFOS produced a dose-dependent accumulation of this chemical in various body tissues, including the brain. PFOS exposure decreased food intake and BW in a dose-dependent manner. Treatment with PFOS affected estrous cyclicity and increased serum corticosterone levels while decreasing serum leptin concentrations. PFOS treatment also increased norepinephrine concentrations in the paraventricular nucleus of the hypothalamus. These results indicate that exposure to PFOS can affect the neuroendocrine system in rats. PMID:12948888

  8. Hypertension in rats deficient in copper

    SciTech Connect

    Klevay, L.M.

    1986-03-01

    Male weanling rats were matched into two groups of equal mean weight (48 g), were fed a diet low in copper and zinc and were supplemented with a drinking solution with 10..mu..gZn and 2/sup +/gCu per ml until they grew to approximately 300 g. Systolic blood pressure (mmHg) was measured without anesthesia with an Electro-Sphygmomanometer and pneumatic pulse transducer; no significant difference between groups was found (0 > 0.05). Then copper was omitted from the solution of the group with lower blood pressure in each of two experiments. Plasma cholesterol (mg/dl) was measured by fluorometry and blood pressure was measured again 53 to 86 days later; mean (SE), n = 14, 15. Hypercholesterolemia verified deficiency. Hypotension in copper deficient rats in experiments of others probably was the result of cardiac defects induced in weanling animals. Hypertension joins hypercholesterolemia, hyperuricemia, glucose intolerance and abnormal electrocardiograms as a stigma of copper deficiency. Copper deficiency is the only nutritional insult that induces all of these characteristics useful in predicting risk of ischemic heart disease.

  9. Interactions between respiratory oscillators in adult rats.

    PubMed

    Huckstepp, Robert Tr; Henderson, Lauren E; Cardoza, Kathryn P; Feldman, Jack L

    2016-01-01

    Breathing in mammals is hypothesized to result from the interaction of two distinct oscillators: the preBötzinger Complex (preBötC) driving inspiration and the lateral parafacial region (pFL) driving active expiration. To understand the interactions between these oscillators, we independently altered their excitability in spontaneously breathing vagotomized urethane-anesthetized adult rats. Hyperpolarizing preBötC neurons decreased inspiratory activity and initiated active expiration, ultimately progressing to apnea, i.e., cessation of both inspiration and active expiration. Depolarizing pFL neurons produced active expiration at rest, but not when inspiratory activity was suppressed by hyperpolarizing preBötC neurons. We conclude that in anesthetized adult rats active expiration is driven by the pFL but requires an additional form of network excitation, i.e., ongoing rhythmic preBötC activity sufficient to drive inspiratory motor output or increased chemosensory drive. The organization of this coupled oscillator system, which is essential for life, may have implications for other neural networks that contain multiple rhythm/pattern generators. PMID:27300271

  10. Tropical rat mites (Ornithonyssus bacoti) - serious ectoparasites.

    PubMed

    Beck, Wieland; Fölster-Holst, Regina

    2009-08-01

    In Germany there is limited information available about the distribution of the tropical rat mite (Ornithonyssus bacoti) in rodents. A few case reports show that this hematophagous mite species may also cause dermatitis in man. Having close body contact to small rodents is an important question for patients with pruritic dermatoses. The definitive diagnosis of this ectoparasitosis requires the detection of the parasite, which is more likely to be found in the environment of its host (in the cages, in the litter or in corners or cracks of the living area) than on the hosts' skin itself. A case of infestation with tropical rat mites in a family is reported here. Three mice that had been removed from the home two months before were the reservoir. The mites were detected in a room where the cage with the mice had been placed months ago. Treatment requires the eradication of the parasites on its hosts (by a veterinarian) and in the environment (by an exterminator) with adequate acaricides such as permethrin. PMID:19508683

  11. Impaired oxidative phosphorylation in overtrained rat myocardium

    PubMed Central

    Kadaja, Lumme; Eimre, Margus; Paju, Kalju; Roosimaa, Mart; Põdramägi, Taavi; Kaasik, Priit; Pehme, Ando; Orlova, Ehte; Mudist, Margareeta; Peet, Nadezhda; Piirsoo, Andres; Seene, Teet; Gellerich, Frank N; Seppet, Enn K

    2010-01-01

    The present study was undertaken to characterize and review the changes in energy metabolism in rat myocardium in response to chronic exhaustive exercise. It was shown that a treadmill exercise program applied for six weeks led the rats into a state characterized by decreased performance, loss of body weight and enhanced muscle catabolism, indicating development of overtraining syndrome. Electron microscopy revealed disintegration of the cardiomyocyte structure, cellular swelling and appearance of peroxisomes. Respirometric assessment of mitochondria in saponin-permeabilized cells in situ revealed a decreased rate of oxidative phosphorylation (OXPHOS) due to diminished control over it by ADP and impaired functional coupling of adenylate kinase to OXPHOS. In parallel, reduced tissue content of cytochrome c was observed, which could limit the maximal rate of OXPHOS. The results are discussed with respect to relationships between the volume of work and corresponding energy metabolism. It is concluded that overtraining syndrome is not restricted to skeletal muscle but can affect cardiac muscle as well. PMID:21264069

  12. Stress-free Microinjections in Conscious Rats

    PubMed Central

    Zaretsky, Dmitry V.; Zaretskaia, Maria V.; Rusyniak, Daniel E.; DiMicco, Joseph A.

    2011-01-01

    Microinjections are a major tool in modern neuroscience. Microinjection techniques in conscious animals typically involve four steps: 1) animal adapts to experimental setup; 2) injection system is filled and the microinjector is carefully inserted; 3) a drug solution is injected; 4) one to two minutes later the microinjector is carefully removed. Steps 2 and 4 are difficult to perform in rodents without disturbing the animal. This disruption can cause stress and accompanying tachycardia and hyperthermia - unwanted artifacts in physiological research. To reduce these effects, we altered the traditional approach. Our procedure of microinjection consisted of the following steps: 1) We filled the injection setup and fixed the microinjector in its guide cannula; 2) allowed an animal to adapt to the setup; 3) performed an experiment including microinjection(s); 4) removed the microinjector after the experiment was complete. The key change we incorporated was a one meter long piece of tubing with a small internal diameter; it allowed us to inject nanoliter volumes through the injector which had been placed into the guide cannula in advance. This way we avoided the usual manipulations related to microinjection, and minimized extraneous disturbances to the rat. In this report we describe the details of this technique in conscious rats and provide examples of the effects and the reproducibility of a 100 nL drug injection on cardiovascular function. PMID:21600924

  13. Urodynamic characteristics of rats with detrusor instability.

    PubMed

    Liu, Di; Wang, Haipeng; Wang, Longwang; Ma, Yan; Han, Xiaomin; Li, Bing; Zhang, Xiaoping; Xiao, Yajun; Zeng, Fuqing; Pan, Feng

    2014-12-01

    The purpose of the present study is to investigate urodynamic characteristics of rats with detrusor instability (DI) induced by different causes. Forty-eight adult female Sprague-Dawly rats were randomly divided into 4 groups: cyclophosphamide group, bladder outlet obstruction group, lipopolysaccharide group and control group. The BL-410 model bio-function experimental system was applied to monitor bladder pressure and a number of urodynamic parameters were recorded and calculated, including the frequency of detrusor instability, maximum voiding pressure (MVP), maximum cystometric capacity (MCC), intercontraction interval (ICI), voiding time (VT), postvoid residual (PVR) and bladder compliance (BC). The positive rates of DI in cyclophosphamide group, bladder outlet obstruction group and lipopolysaccharide group were 83.33%, 75.00% and 58.33%, respectively. And correspondingly the frequency of DI was 10.00±2.00, 4.87±1.24 and 3.50±1.00tmin(-1), which was significantly higher than those of the control group (P<0.05). Compared with the control group, the decrease of MVP, MCC, ICI, VT and BC was noted in the cyclophosphamide group and lipopolysaccharide group. Increased PVR, MVP, MCC, VT and BC were presented in the bladder outlet obstruction group. Therefore, we suggested that the urodynamic parameters could reflect the pathophysiological characteristics of DI induced by different causes, which could systematically benefit the diagnosis and treatment of overactive bladder. PMID:25450213

  14. Development toxicity of cobalt in the rat

    SciTech Connect

    Paternain, J.L.; Domingo, J.L.; Corbella, J.

    1988-01-01

    To determine the potential developmental toxicity of cobalt, pregnant Sprague-Dawley rats were given by gavage a daily dose of 0, 25, 50, and 100 mg/kg cobalt(II) chloride on d 6-15 of gestation. Females were sacrificed on d 20. Maternal effects included significant reductions in weight gain and food consumption, particularly at 100 mk/kg x d. Hematocrit, hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin, and reticulocytes were increased significantly in the 100-mg/kg x d group. No treatment-related changes were recorded in the number of corpora lutea, total implants, resorptions, the number of live and dead fetuses, fetal size parameters, or fetal sex distribution data. Increased incidence of stunted fetuses per litter was the only adverse finding at 50 and 100 mg/kg x d group. However, this increase was not statistically significant. Examination of fetuses for gross external abnormalities, skeletal malformation, or ossification variations revealed that cobalt did not produce teratogenicity or significant fetotoxicity in the rat at doses as high as 100 mg/kg x d.

  15. Modification of radiation damage in rat spinal cord by mitotane

    SciTech Connect

    Glicksman, A.S.; Bliven, S.F.; Leith, J.T.

    1982-07-01

    Modification of the paralytic response in rats after 6-MV photon irradiation of the spinal cord with either single or split exposures (two equal fractions given in a 24-hour period) by mitotane was investigated. Mitotane was administered as a suspension in physiologic saline (300 mg/kg/day) for either 5 days prior to or 5 days after irradiation. For rats receiving split doses of 6-MV photons, either the last two doses of mitotane were given 2 hours prior to each radiation fraction or mitotane was begun 2 hours after the second fraction and continued for 5 days. The data to 6 months after irradiation indicate that, in rats given mitotane for 5 days prior to single-dose photon irradiation, the paralytic response (as defined by the dose needed to produce paralysis in 50% of the irradiated groups of rats) was enhanced by a dose-enhancement factor (DEF) of 1.40. The DEF in the group of rats given mitotane after single doses of 6-MV photons was 1.15. In the split-dose irradiation experiments, the DEF for the groups of rats given mitotane prior to each radiation fraction was 1.36; while the DEF for the group of rats receiving mitotane beginning after the second fraction was 1.18. These data indicate that mitotane can potentiate the effects of 6-MV photon irradiation to the central nervous system, with mitotane administered prior to irradiation being the most effective sequence.

  16. Brain Injury After Intracerebral Hemorrhage in Spontaneously Hypertensive Rats

    PubMed Central

    Wu, Gang; Bao, Xuhui; Xi, Guohua; Keep, Richard; Thompson, B. Gregory; Hua, Ya

    2011-01-01

    Object Hypertension is the main cause of spontaneous intracerebral hemorrhages (ICH), but the effects of hypertension on ICH-induced brain injury have not been well studied. In this study, we examined ICH-induced brain injury in spontaneously hypertensive rats (SHR). Methods This two-part study was performed on 12 weeks old male SHR and Wistar Kyoto (WKY) rats. First, rats received an intracaudate injection of 0.3 units collagenase and hematoma sizes were determined at 24 hours. Second, rats were injected with 100-μL autologous whole blood into the right basal ganglia. Brain edema, neuronal death, ferritin expression, microglia activation, and neurological deficits were examined. Results Hematoma sizes were the same in SHR and WKY rats 24 hours after collagenase injection. SHR had greater neuronal death and neurological deficits after blood injection. ICH also resulted in higher brain ferritin levels and stronger activation of microglia in SHR. However, perihematomal brain edema was same in the SHR and WKY rats. Conclusion Moderate chronic hypertension resulted in more severe ICH-induced neuronal death and neurological deficits, but did not exaggerate hematoma enlargement and perihematomal brain edema in the rat ICH models. PMID:21294617

  17. Aminohydroxybutane bisphosphonate inhibits bone loss due to immobilization in rats.

    PubMed

    Thompson, D D; Seedor, J G; Weinreb, M; Rosini, S; Rodan, G A

    1990-03-01

    The purpose of this study was to document the effects of aminobutane bisphosphonate (AHBuP) on bone remodeling during immobilization in rats. Male Sprague-Dawley rats underwent unilateral sciatic neurectomy after receiving two daily subcutaneous injections of 0, 0.01, 0.10, or 1.0 mg P per kg AHBuP. Rats were sacrificed at 24 h or 10 or 20 days postimmobilization. Femora were ashed and tibiae were prepared for histomorphometric analysis. AHBuP was effective in inhibiting bone loss due to immobilization in a dose-dependent manner. The percentage loss of femoral ash weight due to immobilization decreased in a dose-dependent manner. In vehicle-treated rats, there was a significant decrease in trabecular bone volume (TBV) in the immobilized tibiae compared to the normal tibiae; in AHBuP-treated rats there was a dose-dependent increase in TBV both in the immobilized and control tibiae. The osteoid surface extent was decreased in AHBuP-treated rats in a dose-dependent manner. The mineral apposition rate was altered only in the intact leg of rats treated with 0.1 and 1.0 mg P AHBuP per kg compared to vehicle treated. Osteoclast number per mm was reduced by AHBuP treatment. In conclusion, aminohydroxybutane bisphosphonate effectively prevented the bone loss due to immobilization in this system. PMID:2333787

  18. Effects of photoradiation therapy on normal rat brain

    SciTech Connect

    Cheng, M.K.; McKean, J.; Boisvert, D.; Tulip, J.; Mielke, B.W.

    1984-12-01

    Laser photoradiation of the brain via an optical fiber positioned 5 mm above a burr hole was performed after the injection of hematoporphyrin derivative (HpD) in 33 normal rats and 6 rats with an intracerebral glioma. Normal rats received HpD, 5 or 10 mg/kg of body weight, followed by laser exposure at various doses or were exposed to a fixed laser dose after the administration of HpD, 2.5 to 20 mg/kg. One control group received neither HpD nor laser energy, and another was exposed to laser energy only. The 6 rats bearing an intracranial 9L glioma were treated with HpD, 5 mg/kg, followed by laser exposure at various high doses. The temperature in the cortex or tumor was measured with a probe during laser exposure. The rats were killed 72 hours after photoradiation, and the extent of necrosis of cerebral tissue was measured microscopically. In the normal rats, the extent of brain damage correlated with increases in the dose of both the laser and the HpD. In all 6 glioma-bearing rats, the high laser doses produced some focal necrosis in the tumors but also damaged adjacent normal brain tissue. The authors conclude that damage to normal brain tissue may be a significant complication of high dose photoradiation therapy for intracranial tumors.

  19. Aromatized testosterone attenuates contextual generalization of fear in male rats.

    PubMed

    Lynch, Joseph F; Vanderhoof, Tyler; Winiecki, Patrick; Latsko, Maeson S; Riccio, David C; Jasnow, Aaron M

    2016-08-01

    Generalization is a common symptom of many anxiety disorders, and females are 60% more likely to suffer from an anxiety disorder than males. We have previously demonstrated that female rats display significantly accelerated rates of contextual fear generalization compared to male rats; a process driven, in part, by activation of ERβ. The current study was designed to determine the impact of estrogens on contextual fear generalization in male rats. For experiment 1, adult male rats were gonadectomized (GDX) and implanted with a capsule containing testosterone proprionate, estradiol, dihydrotestosterone proprionate (DHT), or an empty capsule. Treatment with testosterone or estradiol maintained memory precision when rats were tested in a different (neutral) context 1day after training. However, male rats treated with DHT or empty capsules displayed significant levels of fear generalization, exhibiting high levels of fear in the neutral context. In Experiment 2, we used acute injections of gonadal hormones at a time known to elicit fear generalization in female rats (e.g. 24h before testing). Injection treatment followed the same pattern of results seen in Experiment 1. Finally, animals given daily injections of the aromatase inhibitor, Fadrozole, displayed significant fear generalization. These data suggest that testosterone attenuates fear generalization likely through the aromatization testosterone into estradiol as animals treated with the non-aromatizable androgen, DHT, or animals treated with Fadrozole, displayed significant generalized fear. Overall, these results demonstrate a sex-dependent effect of estradiol on the generalization of contextual fear. PMID:27368147

  20. Metabolic fate of S-(-)-pulegone in rat.

    PubMed

    Madyastha, K M; Gaikwad, N W

    1998-08-01

    1. S-(-)-pulegone was administered orally to rat (250 mg/kg) and the nature of the urinary metabolites was investigated. Eleven metabolites, namely S-(-)-menthofuran, piperitone, piperitenone, p-cresol, 5-hydroxypulegone, 4-methylcyclohexenone, 3-methylcyclohexanone, isopulegone, pulegol, 7-hydroxypiperitone and benzoic acid, have been isolated from rat urine. It is assumed that menthofuran, isopulegone and 4-methylcyclohexenone retain the stereochemistry of the parent compound, whereas in other metabolites the stereochemistry at the asymmetric centres is not known. 2. The relative amounts of various major metabolites present in the total urine extracts from the R-(+) and S-(-)-pulegone-treated rat were established by glc analyses. Urine samples of rats treated with R-(+)-pulegone contained higher levels of p-cresol and piperitenone than in similar experiment carried out with S-(-)-pulegone, whereas the levels of unmetabolized pulegone, piperitone and benzoic acid were considerably higher in the urine of rat treated with S-(-)-pulegone than in a corresponding experiment with R-(+)-pulegone. 3. Phenobarbital-induced rat liver microsomes converted S-(-)-pulegone to S-(-)-menthofuran (VII) and piperitenone (III) in the presence of NADPH and O2. The levels of VII and III were significantly higher in similar experiments carried out with R-(+)-pulegone. 4. Based on these studies, metabolic pathways for the biotransformation of S-(-)-pulegone in rat have been proposed and possible reasons for the observed difference in the toxicity mediated by these two enantiomers are discussed. PMID:9741951