Synaptic transmission at nicotinic acetylcholine receptors in rat hippocampal organotypic cultures and slices

作     者：Hefft, S Hulo, S Bertrand, D Muller, D 

作者机构：Ctr Med Univ Geneva Dept Physiol CH-1211 Geneva 4 Switzerland 

出 版 物：《JOURNAL OF PHYSIOLOGY-LONDON》 (生理学杂志)

年 卷 期：1999年第515卷第3期

页      面：769-776页

核心收录：

学科分类：0710[理学-生物学] 1001[医学-基础医学(可授医学、理学学位)] 07[理学] 071003[理学-生理学] 

主　　题：乌头碱/类似物和衍生物 乌头碱/药理学 环蛇毒素类/药理学 诱发电位/药物作用 兴奋性氨基酸拮抗剂/药理学 GABA拮抗剂/药理学 海马/生理学 烟碱拮抗剂/药理学 器官培养技术 印防己毒素/药理学 哌嗪类/药理学 锥体细胞/药物作用 锥体细胞/生理学 喹恶啉类/药理学 大鼠 Sprague-Dawley 受体 烟碱/生理学 突触传递/药物作用 突触传递/生理学 筒箭毒碱/药理学 动物 大鼠 

摘      要：1. Whole-cell clamp recordings of the compound synaptic current elicited by afferent stimulation of Schaffer collaterals showed that blockade of the NMDA, AMPA. and GABA, receptor-mediated components by 6-nitro-7-sulphamoyl-benzo(f)quinoxaline-2,3-dione (NBQX), 3-((R)2-carboxypiperazine-4-yl)propyl-1-phosphonate (R-CPP) and picrotoxin, respectively, left a small residual current in 39 out of 41 CA1 pyramidal neurones in organotypic cultures and 9 out of 16 CA1 cells in acutely prepared slices. 2. This current represented 2.9 +/- 0.1% of the compound evoked synaptic response in organoypic cultures and 1.4 +/- 0.5% in slices. It was characterized by a slightly rectifying I-V curve and a reversal potential of 3.4 +/- 5.1 mV. 3. This residual current was insensitive to blockers of GABA(B), purinergic, muscarinic and 5-HT3 receptors, but it was essentially blocked by the nicotinic receptor antagonist d-tubocurarine (91 +/- 4% blockade;20 mu M), and partly blocked by alpha-bungarotoxin (200 nM) and methyllycaconitine (10 nM), two antagonists with a higher selectivity for alpha 7 subunit-containing nicotinic receptors (48 +/- 3% and 55 +/- 11% blockade, respectively). 4. The residual current was of synaptic origin, since it occurred after a small delay;its amplitude depended upon the stimulation intensity and it was calcium dependent and blocked by the sodium channel antagonist tetrodotoxin. 5. We conclude that afferent stimulation applied in the stratum radiatum evokes in some hippocampal neurones a small synaptic current mediated by activation of neuronal nicotinic receptors.