دورية أكاديمية

Distinct muscarinic acetylcholine receptor subtypes mediate pre- and postsynaptic effects in rat neocortex

التفاصيل البيبلوغرافية
العنوان: Distinct muscarinic acetylcholine receptor subtypes mediate pre- and postsynaptic effects in rat neocortex
المؤلفون: Gigout, Sylvain, Jones, Gareth A, Wierschke, Stephan, Davies, Ceri H, Watson, Jeannette M, Deisz, Rudolf A
بيانات النشر: BioMed Central Ltd.
سنة النشر: 2012
المجموعة: BioMed Central
مصطلحات موضوعية: Carbachol, M-current, Muscarinic acetylcholine receptors, Sensorimotor cortex, Cognition, Synaptic transmission
الوصف: Background Cholinergic transmission has been implicated in learning, memory and cognition. However, the cellular effects induced by muscarinic acetylcholine receptors (mAChRs) activation are poorly understood in the neocortex. We investigated the effects of the cholinergic agonist carbachol (CCh) and various agonists and antagonists on neuronal activity in rat neocortical slices using intracellular (sharp microelectrode) and field potential recordings. Results CCh increased neuronal firing but reduced synaptic transmission. The increase of neuronal firing was antagonized by pirenzepine (M 1 /M 4 mAChRs antagonist) but not by AF-DX 116 (M 2 /M 4 mAChRs antagonist). Pirenzepine reversed the depressant effect of CCh on excitatory postsynaptic potential (EPSP) but had marginal effects when applied before CCh. AF-DX 116 antagonized the depression of EPSP when applied before or during CCh. CCh also decreased the paired-pulse inhibition of field potentials and the inhibitory conductances mediated by GABA A and GABA B receptors. The depression of paired-pulse inhibition was antagonized or prevented by AF-DX 116 or atropine but only marginally by pirenzepine. The inhibitory conductances were unaltered by xanomeline (M 1 /M 4 mAChRs agonist), yet the CCh-induced depression was antagonized by AF-DX 116. Linopirdine, a selective M-current blocker, mimicked the effect of CCh on neuronal firing. However, linopirdine had no effect on the amplitude of EPSP or on the paired-pulse inhibition, indicating that M-current is involved in the increase of neuronal excitability but neither in the depression of EPSP nor paired-pulse inhibition. Conclusions These data indicate that the three effects are mediated by different mAChRs, the increase in firing being mediated by M 1 mAChR, decrease of inhibition by M 2 mAChR and depression of excitatory transmission by M 4 mAChR. The depression of EPSP and increase of neuronal firing might enhance the signal-to-noise ratio, whereas the concomitant depression of inhibition would ...
نوع الوثيقة: article in journal/newspaper
اللغة: English
العلاقة: http://www.biomedcentral.com/1471-2202/13/42Test
الإتاحة: http://www.biomedcentral.com/1471-2202/13/42Test
حقوق: Copyright 2012 Gigout et al.; licensee BioMed Central Ltd
رقم الانضمام: edsbas.5D446451
قاعدة البيانات: BASE