Neuronal nicotinic α-bungarotoxin receptors
Recent evidence has indicated that the nicotinic acetylcholine receptor and the nicotinic α-bungarotoxin (α-BGT) site may be distinct in neuronal tissues. With regard to function, the former receptor appears to be involved in mediating synaptic events; however, the role of the nicotinic α-BGT site in nervous tissue is currently not known. Since the binding of α-BGT exhibits such high affinity and selectivity for a specific receptor, this may implicate an involvement of the toxin binding site in some aspect of neuronal activity with the receptor possibly mediating functions other than nicotinic cholinergic transmission. A further hypothesis to explain the nature of the toxin binding site may be that the natural ligand for the α-BGT site is one other than acetylcholine, with acetylcholine acting as a modulator of the site. Current studies in our laboratory are exploring these possibilities by determining whether specific peptides and/or polypeptides can interact at the nicotinic α-BGT site in nervous tissue. Studies using both in vivo and in vitro approaches suggest that thy-mopoietin may serve a role as a modulator of the nicotinic α-BGT site in neuronal tissues.
KeywordsChromaffin Cell Nicotinic Receptor Nicotinic Acetylcholine Receptor Neuronal Tissue Adrenal Chromaffin Cell
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