... Title : Beta-Adrenergic Receptors Regulating Growth and Replication of ... Receptor stimulation by isoproterenol evoked immediate reductions in ...

C6 glioma cells and B104 neuroblastoma cells both possess adenylate cyclase activity, but only C6 cells have beta-adrenergic receptors. However, when cocultured with B104 cells, C6 cells show a marked decrease in their ability to accumulate cyclic AMP upo...

The invention relates to a fat cell specific beta-adrenergic receptor that mediates lipolysis. The invention further relates to cloned cells which code for the specific beta-adrenergic receptor that mediates lipolysis. Another aspect of the invention rela...

Unweighting, but not denervation, of muscle reportedly 'spares' insulin receptors, increasing insulin sensitivity. Unweighting also increases beta-adrenergic responses of carbohydrate metabolism. These differential characteristics were studied further by ...

... Receptor stimulation by beta-agonists, or administration of the phosphodiesterase inhibitor, theophylline, led to mitotic arrest and a consequent ...

C6 glioma cells and B104 neuroblastoma cells both possess adenylate cyclase activity, but only C6 cells have ..beta..-adrenergic s. However, when cocultured with B104 cells, C6 cells show a marked decrease in their ability to accumulate adenosine 3',5'-monophosphate upon stimulation with ..beta.. receptor agonists. ...

C6 glioma cells and B104 neuroblastoma cells both possess adenylate cyclase activity, but only C6 cells have beta-adrenergic receptors. However, when cocultured with B104 cells, C6 cells show a marked decrease in their ability to accumulate cyclic AMP upon stimulation with beta-agonists. Since both beta-receptors ...

In analyzing the effects of hyperbaric helium-oxygen on alpha and beta adrenergic receptors of rabbit duodenum, norepinephrine latency was found to vary directly and linearly with the increase in pressure. This relationship is described by the equation Y ...

... The phosphodiesterase inhibitor, theophylline, reduced cell number and altered cellular morphology. In the current year ...

The study defined the normal ontogenic patterns of ODC and its responsiveness to direct beta-adrenergic stimulation, and provided a data base that will be used in future studies on alterations of cardiac development following prenatal insult. In the adult...

A-10 cells which are derived from embryonic rat thoracic aorta contain a high density of vasopressin receptors and relatively fewer ..beta..-adrenergic receptors. The effects of vasopressin binding to these cells are two-fold: a) inhibition of isoproterenol-stimulated cAMP accumulation, and; b) stimulation of ...

... These medications have included heparin, warfarin, beta-adrenergic receptor blockers, calcium channel antagonists, angiotensin converting enzyme inhibitors ...

... This study explores P3-adrenoceptors on breast cancer cells as a therapeutic target. MDA-MB-231 human breast cancer cells express high 12 ...

... catalytic response exemplified by Mn 21, whereas after 3-4 days in culture, the two stimulations were indistinguishable: isoproterenol ...

Chronic ethanol consumption disrupts G protein-dependent signaling pathways in rat adipocytes. Because lipolysis in adipocytes is regulated by G protein-mediated cAMP signal transduction, we hypothesized that cAMP-regulated lipolysis may be vulnerable to long-term ethanol exposure. Male Wistar rats were fed a liquid diet containing ethanol as 35% of total calories or pair-fed a control diet that ...

Beta adrenergic receptor binding was performed with /sup 125/I iodocyanopindolol on human cavernous tissue membrane fractions from normal tissue and transsexual procedures obtained postoperatively, as well as from postmortem sources. Isotherm binding studies on normal fresh tissues indicated that the receptor ...

Beta Adrenergic Receptor (AR) Signaling as a novel target for optimizing skin wound healing Contact-blocker). � Development of novel therapies for skin wound healing for other chronic wounds (diabetic foot ulcers, pressure of care for venous ulcers is compression dressing and leg elevation, and adjunctive therapies

Concanavalin A (Con A) is a tetrameric plant lectin that disrupts plasma membrane-cytoskeletal interactions and alters plasma membrane fluidity. We used Con A as a probe to explore beta-adrenergic and muscarinic cholinergic receptor-mediated regulation of cAMP in intact neonatal rat ventricular myocytes. Preincubation with Con A, 0.5 micrograms/ml, ...

Beta adrenergic receptor blocking agents were used in the treatment of 15 hypertensive aircrew who had failed to respond to thiazide diuretics. Atenolol (Tenormin) resulted in adequate control of blood pressure in all subjects. Side effects were minimal and insignificant. It is recommended that a cardio-selective, water-soluble beta ...

Beta-adrenergic receptor concentration and adenylate cyclase activity change with macrophage activation. Resident (R) and thioglycollate (TG) - stimulated macrophages (M phi) have comparable concentrations of beta-adrenergic receptors (2136 + or - 143 and...

Beta-Adrenergic receptor concentration and adenylate cyclase activity change with macrophage activation. Resident (R) and thioglycollate (TG)-stimulated macrophages (M0) have comparable concentrations of beta-adrenergic receptors (2136 + or - 143 and 2110...

Experiments were performed on segments of terminal guinea-pig ileum utilizing differential alpha and beta adrenergic receptor site blocking techniques. Phenylephrine caused a contraction of this segment of guinea-pig intestine which resembled a pure alpha...

The localization and number of beta adrenergic receptors were directly compared in the brains of rats and guinea pigs. The time course of association and saturability of (125I)cyanopindolol (CYP) binding to slide-mounted tissue sections was similar in rats (Kd = 17 pM) and guinea pigs (Kd = 20 pM). The beta-1 and beta-2 ...

Although (-)-/sup 125/I-iodopindolol (IPIN) can be used to label beta-adrenergic receptors in the central nervous system (CNS) in vivo, use of this ligand for receptor imaging studies in humans may be limited due to its relatively poor penetration into the CNS. A series of derivatives related to pindolol was therefore studied in an ...

Fusion of normal, untreated human erythrocytes with desensitized turkey erythrocytes increases isoproterenol stimulation of cyclic (/sup 3/H)AMP accumulation over basal rates. Moreover, pretreatment of the human erythrocytes with cholera toxin before they are fused with desensitized turkey erthythrocytes leads to a large stimulation with isoproterenol. This is even greater and ...

We have investigated beta-adrenergic regulation of adenylate cyclase activity in heart tissue membranes from the genetically obese Zucker rat, the genetically obese CBA mouse and the genetically obese diabetic (db/db) mouse. Responsiveness to beta-adrenergic stimulation was impaired in membranes from the obese Zucker rat, but not in the other models. The membranes from obese ...

The present invention relates to compounds that alter GPCR internalization and new methods for their identification. Compounds of this invention include modified phosphoinositide 3-kinase (PI3K), modified HEAT domain, modified (Beta)-adrenergic receptor k...

The possibility that increased beta-adrenergic receptor stimulation might be operative in the production of cardiovascular malformations in rats was studied by exposing pregnant animals to salicylates which produce some cardiovascular defects, and attempt...

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Previous studies from our laboratory demonstrated that 8 weeks after the induction of diabetes by the administration of streptozotocin (STZ) there was a downregulation of beta adrenergic and muscarinic cholinergic receptors in rat prostate, and that early insulin treatment (started 3 days after the onset of diabetes) prevented these ...

A dose-dependent impairment of intrinsic myocardial performance has been observed following in vivo administration of endotoxin. The present study reports a dose-dependent increase in plasma catecholamines following endotoxin (ET) that may impair ..beta..-adrenergic responsiveness. Hearts were removed from pentobarbital-anesthetized rats 4 h after a bolus injection of saline ...

The tone of arterial blood vessels is regulated by the catecholamines through their receptors on arterial smooth muscle cells (ASMC). ..beta..-/sub 2/-adrenergic receptors of ASMC mediate vasodilation through agonist mediated c-AMP production. Previous reports have described these receptors on freshly isolated blood vessels. This study ...

Canine cardiac beta-adrenergic receptors contain a free sulfhydryl group in the adrenergic ligand binding site. (/sup 125/I)-Iodohydroxybenzylpindolol ((/sup 125/I)-IHYP) binding to cardiac beta-receptors was inhibitied 80% by treatment with 1 mM p-chloromercuribenzoic acid (pCMB). Occupation of the beta-receptors ...

RationalePrevious in vitro research demonstrated that ascorbate enhances potency and duration of activity of agonists binding to alpha 1 adrenergic and histamine receptors.ObjectivesExtending this work to beta 2 adrenergic systems in vitro and in vivo.MethodsUltraviolet spectroscopy was used to study ascorbate binding to adrenergic receptor preparations ...

Beta-adrenergic signaling mechanisms are of central importance to cardiovascular health and disease. Modulation of these pathways represents an important pharmacologic approach to the treatment of heart failure and hypertension. Advances in molecular genetics have identified genetic polymorphisms in the human beta-adrenergic receptor ...

Radioligand binding studies were performed to determine whether upregulation of postjunctional beta receptors occurs in sympathectomized hearts of aged animals. Fischer 344 rats 6, 12, and 24 months of age (n = 10) were used in these experiments. To produce sympathectomy, rats were injected with 6-hydroxydopamine hydrobromide (6-OHDA; 2 x 50 mg/kg iv) on days 1 and 8; the ...

We have found natural products exhibiting lipolysis-promoting activity in subcutaneous adipocytes, which are less sensitive to hormones than visceral adipocytes. The activities and a action mechanisms of a novel plant extract of Cirsium oligophyllum (CE) were investigated in isolated adipocytes from rat subcutaneous fat, and its fat-reducing effects by peroral administration and topical ...

Purified preparations of microvessels from bovine cerebral cortex contain substantial levels of alpha-adrenergic, beta-adrenergic, and histamine 1 receptor binding sites but only negligible serotonin, muscarinic cholinergic, opiate, and benzodiazepine receptor binding. Norepinephrine and histamine may be endogenous regulators of the ...

Beta adrenergic receptors are very important in respiratory medicine. Traditionally, the stimulation of beta adrenergic receptors by beta2-agonists is commonly used for giving bronchodilation in chronic airflow obstruction However; the wide distribution of these ...

The goal of this research was to determine the effects of [beta]-adrenergic antagonism in the IC before or after inhibitory avoidance (IA) training or context pre-exposure in a latent inhibition protocol. Pretraining intra-IC infusion of the [beta]-adrenergic antagonist propranolol disrupted subsequent IA retention and impaired latent inhibition of IA, but had no effect on formation of memory for ...

Hypertension is a pervasive and growing health concern. The occurrence of hypertension due to systemic vasoconstriction in patients before, during, and after surgery is not uncommon and can have serious consequences with regard to outcomes. Careful evaluation prior to surgery to identify the underlying cause of hypertension is important in selecting the best treatment option. Preoperative ...

Exposure to the phorbol ester, phorbol 12-myristate, 13-acetate for 10 minutes enhanced cyclic AMP accumulation in human neutrophils under basal conditions and in response to the beta-adrenergic receptor agonist isoproterenol (ISO, 1{mu}M) and the adenylate cyclase activator forskolin (FSK, 10mM). Potentiation of responses to ISO by PMA was dose-dependent ...

Beta-adrenergic agonists, adenosine and prostaglandin E/sub 1/ increased the level of adenosine 3' : 5'-monophosphate (cAMP) in glial cultures prepared from rat cerebral cortical tissue. In addition to these physiological effectors, cholera toxin also increased cAMP levels in these cultures. The accumulation of cAMP in response to each of ...

The purpose of this study was to determine if 5-hydroxytryptamine released from aggregating platelets could be accumulated and released by canine coronary adrenergic nerves, and if the false neurotransmitter resulted in an abnormal response of the smooth muscle to nerve stimulation. Isometric tension was measured in rings of epicardial coronary suspended in organ chambers ...

Glucocorticoids and adrenergic stimulation are both thought to control the development of beta-adrenergic receptors/responses. In the current study, rats were exposed to dexamethasone or terbutaline during late gestation and the development of beta-bindin...

Beta-adrenergic blocking agents are an increasingly important class of drugs to the family physician. Diseases such as ischemic heart disease, hypertension and hyperthyroidism have responded dramatically to beta-blocking therapy. This article summarizes some of the current knowledge on the beta-receptor, the indications for ...

Preincubation of turkey erythrocytes with isoproterenol is associated with (1) 50-60% attenuation of agonist-stimulated adenylate cyclase activity, (2) altered mobility of the ..beta..-adrenergic receptor on sodium dodecyl sulfate-polyacrylamide gels, and (3) increased phosphorylation of the ..beta..-adrenergic receptor. Using a low-cross-linked ...

This study explores beta-adrenoceptors on breast cancer cells as a therapeutic target. MDA-MB-231 human breast cancer cells express high beta2- adrenoceptor levels that are linked to inhibition of mitosis through the production of cyclic AMP. Receptor sti...

The mechanical responses produced by alpha and beta adrenergic receptor agonists were evaluated in control and myenteric neuron-ablated rat jejunal longitudinal muscle. The myenteric plexus of the jejunum was destroyed by serosal application of benzalkonium chloride (BAC). The beta adrenergic ...

The effects of topical application of glucocorticoids on the epidermal beta-adrenergic adenylate cyclase response were investigated. A significant increase in this receptor response was observed 24 h following topical application of potent glucocorticoid ointments (0.12% betamethasone-17-valerate, 0.05% clobetasol-17-propionate). The application of a ...

A disruption of the blood-aqueous barrier in rabbit eyes was elicited by use of topical prostaglandin E2(PGE2), infrared irradiation of the iris, or by subcutaneous alpha-melanocyte-stimulating hormone (alpha-MSH). The aqueous flare provoked was measured quantitatively with a photoelectric instrument. The effect of the (topical) beta-adrenergic antagonist timolol maleate on ...

A disruption of the blood-aqueous barrier in rabbit eyes was elicited by use of topical prostaglandin E2(PGE2), infrared irradiation of the iris, or by subcutaneous alpha-melanocyte-stimulating hormone (alpha-MSH). The aqueous flare provoked was measured quantitatively with a photoelectric instrument. The effect of the (topical) beta-adrenergic antagonist timolol maleate on ...

The (+)-stereoisomers of arylethanolamine beta adrenergic agonists and antagonists are usually much less active in biological systems than their corresponding (-)-forms. In the eye, however, prior physiological studies have shown that these (+)-stereoisomers are unexpectedly potent in altering intraocular pressure, results which could be due to a ...

The mechanisms by which acute hypoxia (10% and 5% oxygen) mediates changes in coronary blood flow and cardiac function were investigated in the conscious dog. When the dogs breathed hypoxic gas mixtures through a tracheostomy, both arterial and coronary s...

This study examines the beta adrenergic receptors of the rabbit detrusor smooth muscle, employing (/sup 125/I)iodocyanopindolol (ICYP) as a ligand for the binding of beta adrenergic receptors. Saturation binding experiments on the isolated membrane fraction yielded a KD for ...

The mammalian ..beta../sub 2/-adrenergic receptor from rat liver has been purified by sequential cycles of affinity chromatography followed by steric-exclusion high performance liquid chromatography. Electrophoresis of highly purified receptor preparations on polyacrylamide gels in the presence of sodium dodecyl sulfate under reducing conditions reveals a ...

Previous studies utilizing the fluorescence of propanolol as a probe for the beta-adrenergic receptor showed that this receptor is motionally constrained. To further study the beta-adrenergic receptor in situ the authors have reinserted rhodamine-labeled beta-receptors into cell membranes. This report presents ...

The ability of catecholamines to modulate cell proliferation, differentiation and morphogenesis in other systems, and modulate adenylate cyclase activity in the developing palate during the period of cellular differentiation, made it of interest to determine their involvement in palatal ontogenesis. Catecholamines exert their physiologic effects via interaction with distinct membrane-bound ...

Xenopus laevis oocytes are a useful transcription and expression system for DNA and RNA, respectively. Total cellular RNA was extracted from mouse lymphoma S49 cells and poly(A)/sup +/mRNA prepared by affinity chromatography of RNA on oligo(dT) cellulose. The membranes of S49 cells contain beta-adrenergic receptors that display pharmacological ...

As age and sex affect the function of the lower urinary tract, we studied the characteristics of adrenergic and cholinergic receptors in various parts of lower urinary tract smooth muscle of young (6 months) and old (4 1/2-5 years) male and female rabbits. Saturation experiments performed with (3H)prazosin, (3H)yohimbine, (3H)dihydroalprenolol and (3H)quinuclidinyl benzylate ...

Partial amino acid sequence information allowed the isolation of cDNA clones encoding the turkey erythrocyte beta-adrenergic receptor. Antisera raised against synthetic peptides encoded by the cDNA crossreacted with the purified receptor and appropriate tryptic fragments, confirming the identity of the cDNA. The ...

The radioactive beta-adrenergic antagonist (/sup 3/H) dihydroalprenolol (DHA) binds to particulate preparations of human myometrium in a manner compatible with binding to the beta-adrenergic receptor. The binding of DHA is rapid (attaining equilibrium in 12 minutes), readily reversible (half time = 16 minutes), high affinity (K/sub D/ = 0.50 nM), low ...

Thermogenesis in brown adipose tissue (BAT) serves as a regulator of body temperature and weight maintenance. Thermogenesis can be stimulated by catecholamine activation of adenylate cyclase through the {beta}-adrenergic receptor. To investigate the effects of sucrose feeding, food deprivation, and cold exposure on the {beta}-adrenergic pathway, adenylate cyclase activity and ...

Agonist-promoted desensitization of adenylate cyclase is intimately associated with phosphorylation of the beta-adrenergic receptor in mammalian, avian, and amphibian cells. However, the nature of the protein kinase(s) involved in receptor phosphorylation remains largely unknown. We report here the identification and partial purification of a protein ...

The paramyxoviruses measles (subacute sclerosing panencephalitis, SSPE) virus and canine distemper virus (CDV) cause an impairment of the catecholamine-induced beta-adrenergic receptor-dependent cAMP generation in persistently infected C6 rat glioma cells. In C6 cells persistently infected with CDV the number of receptors is greatly ...

Beta-adrenergic receptor ligand binding sites have been characterized in synaptic membranes from rat cerebral cortex and cerebellum using radioligand binding techniques. The equilibrium and kinetic properties of binding were assessed. The binding sites were non-interacting and exhibited two states of agonist binding which were sensitive to guanyl ...

Experimental animals were injected intraperitoneally with methotrexate for 3 days. Parotid and submandibular main ducts were cannulated and saliva flow was evoked by either intravenous infusion of acetylcholine or an intravenous injection of benthanechol. Methotrexate was found to reduce significantly mean food consumption, body weight, and parotid gland wet weights. Experimental animal salivary ...

... Accession Number : ADA263544. Title : Beta-Adrenergic Blockade and Lactate Metabolism during Exercise at High Altitude. ...

... Accession Number : ADA256533. Title : Beta-Adrenergic Blockade and Lactate Metabolism during Exercise at High Altitude. ...

(-)-Pindolol, one of the most potent beta-adrenergic receptor antagonists, was radioiodinated using chloramine-T oxidation of carrier-free Na 125I and separated from unreacted pindolol to yield 2200 Ci/mmole (-)-(125I)-iodopindolol ((-)-(125I)-IPin). Mass and ultraviolet spectra confirmed that the iodination occurred on the indole ring, presumably at the 3 ...

The time between the death of an animal and the collection of tissue for ligand binding studies varies from study to study. The authors examined the effect of post-mortem time on ..beta..-adrenergic receptor, affinity, and adenylate cyclase activity. Five cows were sacrificed with an overdose of pentobarbital. The chest was opened and 40 gm sections of left ventricle were ...

Male Sprague Dawley rats were continuously treated in vivo for 6, 12 and 20 hours with a combination of an alpha- (beta-) adrenoreceptor agonist and a beta- (alpha-) adrenoreceptor antagonist in subcutaneously implanted depot tablets. Crude membranes prepared from myocardial cells exhibited a decreased maximum binding of ({sup 125}I)-insulin after 20 hours irrespective of the treatment applied. ...

Hypertension, orthostatic hypotension, arterial insufficiency, and atherosclerosis are common disorders in the elderly that lead to significant morbidity and mortality. One common factor to these conditions is an age-related decline in vascular beta-adrenergic receptor-mediated function and subsequent cAMP generation. Presently, there is no single cellular ...

Hypertension, orthostatic hypotension, arterial insufficiency, and atherosclerosis are common disorders in the elderly that lead to significant morbidity and mortality. One common factor to these conditions is an age-related decline in vascular beta-adrenergic receptor-mediated function and subsequent cAMP generation. Presently, there is no single cellular ...

Beta-adrenergic receptors (?ARs) have long been associated with fear disorders and with learning and memory. However, the contribution of these receptors to Pavlovian fear conditioning, a leading behavioral model for studying fear learning and memory, is still poorly understood. The aim of this study was to investigate the involvement ...

In parotid fragment ({sup 3}H)protein, secretion induced by substance P was moderate, but strongly Ca dependent. However, secretion induced by isoproterenol was large and Ca independent. Potentiation of protein secretion was observed when substance P (SP) and isoproterenol (ISO) acted together. Addition of 10{sup {minus}8} M SP caused a shift to the left in the secretion dose-response curve caused ...

Adrenalectomy caused a large increase in the number of ..beta..-adrenergic binding sites on liver plasma membranes as measured by /sup 125/I-iodocyanopindolol (22 and 102 fmol/mg protein for control and adrenalectomized (ADX) rats). Concomitantly an increase in the number of binding sites for /sup 3/H-yohimbine was also observed (104 and 175 fmol/mg protein for control and adx membranes). ...

Mouse 3T3-L1 fibroblasts contain beta-adrenergic receptors (BAR), predominantly of the B/sub 1/ subtype. Incubation of these cells with 2-10 mM sodium butyrate (SB) for 24-48 hr results in a switch in the BAR subtype from B/sub 1/ to B/sub 2/ and promotes a 1.5 to 2.5 fold increase in total BAR number. Other short chain acids were not as effective as SB in ...

Carp (Cyprinus carpio) liver maintained normal glycogen content and enzyme complement for several days in organ culture. Epinephrine-stimulated glycogenolysis, phosphorylase activation, and cyclic AMP (cAMP) accumulation in a concentration-dependent manner with EC/sub 50/s of 100, 100, and 500 nM, respectively. These actions were blocked by the ..beta..-adrenergic antagonist, ...

Three types of adrenergic receptors, beta, alpha-1, and alpha-2, were identified in human adipocytes, isolated from properitoneal adipose tissue, using both the binding of radioactive ligands and the effects of adrenergic agents on receptor-specific biochemical responses. Adrenergic binding studies showed the following results: ...

Lymphocyte beta adrenergic receptors (lymph BAR) increase after maximal multistage treadmill exercise (TME) presumably by externalization from intracellular vesicles. Nine healthy subjects underwent symptom limited TME by the Bruce protocol. Heart rate was measured at the end of each 3 minute stage. Plasma norepinephrine (NE), plasma ...

Three groups of male, weanling, Sprague-Dawley rats were fed essential fatty acid (EFA) deficient (EFAD), marginally EFA-deficient (MEFAD) or control diets up to 17 weeks. Plasma membranes from heart of EFAD and MEFAD rats had lower basal and fluoride-stimulated adenylate cyclase activity as compared with the controls. The double bond index of total lipids and phospholipids, and fluorescence ...

The objective of this research was two fold: the first objective was to measure ..beta..-adrenergic receptor characteristics (Bmax and Kd) and responsiveness (isoproterenol induced c-AMP production) between different strains of rat with different susceptibility to hypertension. The second objective of this research was to determine if ..beta..-adrenergic ...

Desensitization of adenylate cyclase-coupled ..beta..-adrenergic receptors in avian erythrocytes results in 40-65% decrease in agonist-stimulated adenylate cyclase activity and correlates with increased phosphorylation of ..beta..-adrenergic receptors. To assess the role of phosphorylation in desensitization, membranes from ...

The authors have used radioligand binding techniques and subcellular fraction to assess whether changes in expression of myocardial {alpha}{sub 1}- and {beta}-adrenergic receptors are mediated by a redistribution of receptors between various membrane fractions. Three fractions were prepared from the left ventricles of guinea pigs that underwent either 1 h ...

Treatment of heart failure has been successfully target biologically, to counteract deleterious effects resulting from neuroendocrine activation, with the use of several agents (e.g., angiotensine-converting enzyme inhibitors, beta-adrenergic receptor blockers, spironolactone), that provide benefical effects, demonstrated in multicentric trials in ...

A polypeptide of 8500 molecular weight is described that induces the differentiation of T (thymus-derived) cell and B (bone-marrow-derived) cell immunocytes in vitro, apparently via beta-adrenergic receptors and adenylate cyclase activation. This polypeptide shows a high degree of evolutionary conservation, exhibiting close structural, functional, and ...

In vivo studies have suggested that increased beat-to-beat variability of ventricular repolarization duration (BVR) is a better predictor of drug-induced torsades de pointes than repolarization prolongation alone. Cellular BVR and its dynamics before proarrhythmic events are poorly understood. We investigated differential responses of BVR in single myocytes during I(Ks) blockade versus I(Kr) ...

... This was accomplished by utilization of beta adrenergic blockade (propranolol) under the experimental conditions of constant cardiac output and ...