Title: Muscarinic suppression of a novel voltage-sensitive K+ current in a vertebrate neurone.

Authors: D A Brown, P R Adams

Journal, date & volume: Nature, 1980 Feb 14 , 283, 673-6

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/6965523

Abstract
Cholinergic excitation of vertebrate neurones is frequently mediated through the action of acetylcholine on muscarinic (atropine-sensitve) receptors. This type of excitation differs substantially from the better known nicotinic excitation. One difference is that, instead of an increased membrane conductance, a decreased conductance (to K+ ions) frequently accompanies muscarinic depolarisation. This has been detected in sympathetic, cortical and hippocampal neurones. Using voltage-clamped frog sympathetic neurones we have now identified a distinctive voltage-sensitive K+-current, separate from the delayed rectifier current, as the prime target for muscarinic agonists. We have termed this current the M-current, IM.