... Descriptors : *ADAPTIVE SYSTEMS, *NEUROPHYSIOLOGY, * ACETYLCHOLINE, *GUANOSINE, *BIOCHEMISTRY, ACQUISITION, NEURAL ...

... by black numfber) FIELD GROUP SUB-ROUP Parallel Processing, Ne'ural Networks, Backpropagation, Neurotransmitters, Acetylcholin'e, GAI3A ...

Extensive evidence supports the view that cholinergic mechanisms modulate learning and memory formation. This paper reviews evidence for cholinergic regulation of multiple memory systems, noting that manipulations of cholinergic functions in many neural systems can enhance or impair memory for tasks generally associated with those ...

Examination of the binding characteristics of acetylcholine receptor (AchR) and either tritium labeled acetylcholine ((3H)-Ach) or calcium 45 (45Ca) via a modified Hill plot revealed a decrease in synergistic binding for both acetylcholine (Ach) and calci...

Neural circuits regulate cytokine production to prevent potentially damaging inflammation. A prototypical vagus nerve circuit, the inflammatory reflex, inhibits tumor necrosis factor-? production in spleen by a mechanism requiring acetylcholine signaling through the alpha 7 nicotinic acetylcholine receptor expressed on ...

... Title : Meproadifen Enhances Activitation and Desensitization of the Acetylcholine Receptor-Ionic Channel Complex (AChR): Single Channel ...

, and it generates specific predictions concerning cortical acetylcholine (ACh) release in attention task rights reserved. Theme: Neural basis of behavior Topic: Cognition Keywords: Cortex; Acetylcholine. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 4.1. Alzheimer's disease

Computational modeling assists in analyzing the specific functional role of the cellular e#ects of acetylcholine within cortical structures. In particular, acetylcholine may regulate the dynamics of encoding and retrieval of information by regulating the magnitude of synaptic transmission at excitatory recurrent connections. Many abstract models of ...

We propose a two-layered neural network model for oscillatory phenomena in the thalamic system and investigate an effect of neuromodulation due to the acetylcholine on the oscillatory phenomena by numerical simulations. The proposed model consists of a layer of the thalamic reticular neurons and that of the cholinergic neurons. We introduce a dynamics of ...

Nicotinic acetylcholine receptors mediate fast synaptic transmission by fluxing ions across the membrane in response to neurotransmitter binding. We show here that during affinity purification of the nicotinic acetylcholine receptor from Torpedo, phosphatidic acid, but not other anionic or zwitterionic phospholipids, is hydrolyzed to diacylglycerol. The ...

Nicotinic acetylcholine receptors mediate fast synaptic transmission by fluxing ions across the membrane in response to neurotransmitter binding. We show here that during affinity purification of the nicotinic acetylcholine receptor from Torpedo, phosphatidic acid, but not other anionic or zwitterionic phospholipids, is hydrolyzed to diacylglycerol. The ...

The tonic flexor muscles of the crayfish abdomen respond with a large depolarizing potential to acetylcholine iontophoresed onto a neuromuscular junction, but not to glutamate. Excitatory junctional potentials are abolished by d-tubocurarine and enhanced by a cholinesterase inhibitor. The membrane is depolarized and the junctional potentials are ...

Acetylcholine receptor phosphorylation has been compared in sealed and lysed right-side-out membrane vesicles prepared from Torpedo californica electric organ. Phosphorylation was increased 5- to 12-fold in hypotonically lysed vesicles as compared with untreated vesicles. Control experiments confirm that this enhancement is a result of increased ...

Acetylcholine (ACh) has been shown to modulate neuronal differentiation during early development. Both muscarinic and nicotinic acetylcholine receptors (AChRs) regulate a wide variety of physiological responses, including apoptosis, cellular proliferation and neuronal differentiation. However, the intracellular mechanisms underlying these effects of AChR ...

Even though "procholinergic" drugs are almost the sole kind of treatments currently used as cognitive enhancers in patients with Alzheimer's disease, the role of acetylcholine (ACh) in learning and memory is still poorly understood. In this short review, we focus on the septo-hippocampal cholinergic system and try to demonstrate that understanding ...

Acetylcholine receptors (AChRs) and other postsynaptic molecules cluster spontaneously on cultured C2 myotubes. The frequency of clustering is enhanced by neural agrin, neuraminidase, or calcium through a signaling pathway which includes tyrosine phosphorylation of a muscle-specific kinase (MuSK) and the AChR beta-subunit. Vicia ...

Learning through experience underlies the ability to adapt to novel tasks and unfamiliar environments. However, learning must be regulated so that relevant aspects of the environment are selectively encoded. Acetylcholine (ACh) has been suggested to regulate learning by enhancing the responses of sensory cortical neurons to behaviorally relevant stimuli. ...

The events mediating the differentiation of embryonic neural crest cells into several types of neurons are incompletely understood. In order to probe one aspect of this differentiation, we have examined the capacity of cultured quail trunk neural crest cells to synthesize, from radioactive precursors, and store several putative neurotransmitter compounds. ...

Cortical processing is strongly influenced by the actions of neuromodulators such as acetylcholine (ACh). Early studies in anaesthetized cats argued that acetylcholine can cause a sharpening of orientation tuning functions and an improvement of the signal-to-noise ratio (SNR) of neuronal responses in primary visual cortex (V1). Recent in vitro studies have ...

1. Effects of nicotinic (mecamylamine) and muscarinic (atropine) receptor antagonists were investigated on the secretion of catecholamines evoked by stimulation of splanchnic nerve terminals and acetylcholine in the isolated perfused adrenal gland of the rat to determine whether non-cholinergic substances released from nerve terminals participate in the secretion of ...

... Title : Symbolic Processor Based Models of Neural Networks. ... and Apple computer systems to enhance neural network modeling research were ...

... of an enhanced Feature Space Trajectory Neural Network to speaker ... Feasibility of using Feature Space Trajectory Neural Networks for speaker ...

Whole-body X irradiation (0.155 and 0.310 C/kg) was shown to modify the biphase effect of acetylcholine and GABA on antigradient K+ uptake by rat brain sections. Radiation made the effects of neuromediators on active K+ transport be differently directed: acetylcholine enhanced the inhibitory effect of radiation and GABA restored the ...

The potential for relapse following cessation of drug use can last for years, implying the induction of stable changes in neural circuitry. In hippocampal slices from rats treated with nicotine for 1 week, withdrawal from nicotine in vivo produces an increase in CA1 pyramidal cell excitability that persists up to 9 months. Immediately upon drug cessation the ...

... oscillatory networks in the peripheral olfactory system by ?-aminobutyric acid, glutamate, and acetylcholine in the terrestrial slugLimax marginatus. ... and Etsuro Ito1,4,*. (2003) Distributions of γ-Am...

We investigated the effect of peripherally administered caffeine (50 mg/kg), choline (30, 60, or 120

In the isolated rabbit sinus node, adrenaline induced a pacemaker shift toward the inferior part of the node (distance, 2.5 mm). Acetylcholine gave a pacemaker shift either toward the inferior part of the node (distance, 1.2 mm) or, at higher acetylcholine concentrations, toward cells near the upper part of the crista terminalis. After severing the ...

Dihydroisohistrionicotoxin inhibits acetylcholine receptor-dependent 22Na+ uptake of cultured chick muscle cells with a KI of 0.2 micrometer. The inhibition is noncompetitive with respect to agonists. The toxin enhances desensitization of the receptor by agonists which is accompanied by a 10-fold increase in receptor affinity for agonists. ...

We investigated the interaction between ambient histamine and acetylcholine by studying ? oscillations in rat hippocampus, induced by bath application of acetylcholine (10 �M combined with 2 �M physostigmine). The power of ? was significantly increased by the H1 antagonist, fexofenadine, and H2 receptor agonist, dimaprit, and reduced by the H2 receptor ...

Gradients of acetylcholine can stimulate growth cone turning when applied to neurons grown in culture and it has been suggested that acetylcholine could act as a guidance cue. However, the role acetylcholine plays in directing axon migrations in vivo is not clear. Here, we show that acetylcholine positively ...

1. The release of acetylcholine by parasympathetic ganglion stimulants from the nerve terminals of the guinea-pig longitudinal muscle strip was studied. The acetylcholine released was collected in the presence of physostigmine sulphate. 2. Nicotine and 1,1-dimethyl-4?-phenylpiperazinium iodide (DMPP) released acetylcholine. ...

... In combination with a neural signal, PKC demonstrates a profound synergism enhancing synaptic efficacy. Descriptors ...