Synaptic currents generated by neuronal acetylcholine receptors sensitive to alpha-bungarotoxin.
Nicotinic acetylcholine receptors are widely distributed throughout the nervous system, but their functions remain largely unknown. One of the most abundant is a class of receptors that contains the alpha 7 gene product, has a high relative permeability to calcium, and binds alpha-bungarotoxin. Here, we report that receptors sensitive to alpha-bungarotoxin, though concentrated in perisynaptic clusters on neurons, can generate a large amount of the synaptic current. Residual currents through other nicotinic receptors are sufficient to elicit action potentials, but with slower rise times. This demonstrates a postsynaptic response for alpha-bungarotoxin-sensitive receptors on neurons and suggests that the functional domain of the postsynaptic membrane is broader than previously recognized.
Zhang
Z W
ZW
Department of Biology, University of California, San Diego, La Jolla 92093-0357, USA.
Coggan
J S
JS
Berg
D K
DK
D000109:Acetylcholine / Q000494:pharmacology; D000200:Action Potentials; D000818:Animals; D002038:Bungarotoxins / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002642:Chick Embryo; D002800:Cholinesterase Inhibitors / Q000494:pharmacology; D004553:Electric Conductivity; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D011950:Receptors, Cholinergic / Q000187:drug effects* / Q000502:physiology*; D013569:Synapses / Q000502:physiology*
D002038:Bungarotoxins; D002800:Cholinesterase Inhibitors; D011950:Receptors, Cholinergic; D000109:Acetylcholine