INTRACELLULAR AND EXTRACELLULAR ELECTROPHYSIOLOGY OF NIGRAL DOPAMINERGIC-NEURONS .3. EVIDENCE FOR ELECTROTONIC COUPLING
INTRACELLULAR AND EXTRACELLULAR ELECTROPHYSIOLOGY OF NIGRAL DOPAMINERGIC-NEURONS .3. EVIDENCE FOR ELECTROTONIC COUPLING
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DOI：
10.1016/0306-4522(83)90137-9
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发表时间：
1983-01-01
期刊：
影响因子：
3.3
通讯作者：
BUNNEY, BS
中科院分区：
文献类型：
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作者：
GRACE, AA;BUNNEY, BS
采用3种独立的体内方法，获得了大鼠紧带多巴胺能神经元组间电张力耦合的证据。路西法黄注射到单个多巴胺神经元中，33次注射中有18次标记了2-5个多巴胺神经元。网状结构或神经网状细胞的类似注射未显示多重标记。细胞内记录显示，当膜电位接近放电阈值时，多巴胺神经元自发产生的小（3-15 mV）快速电位经常触发动作电位。这些快速电位的放电速率和模式与之前报道的细胞外记录的多巴胺神经元相似。快速电位在与多巴胺神经元相似的潜伏期从尾状核反方向激活，随后在恒定的潜伏期进行高频反方向刺激，并与自发发生的快速电位碰撞。直接激发的动作电位与反方向激活的快速电位不会发生可靠的碰撞。细胞内注射去极化或超极化电流分别增加和降低这些电位的发生率。静脉注射多巴胺拮抗剂和激动剂可增加和降低快电位放电率。同时对DA神经元的细胞外记录显示了许多同步动作电位的实例。这种情况在静脉注射氟哌啶醇后更为常见。同时记录的多巴胺放电神经元组一致显示，随着脉冲的进展，脉冲间间隔缩短，这一现象在其他电偶联系统中也有报道。电偶联被认为存在于已确定的黑质纹状体多巴胺神经元中。这些神经元之间的电通信可能与调节突发放电和同步释放多巴胺有关。
Using 3 independent in vivo methods evidence for electrotonic coupling between sets of rat zona compacta dopaminergic neurons [DA] was obtained. Lucifer yellow injection into single dopamine neurons resulted in labeling of 2-5 dopamine neurons in 18 out of 33 injections. Similar injections into reticular formation or nigral reticulata cells did not demonstrate multiple labeling. Intracellular recording revealed spontaneously occurring small (3-15 mV) fast potentials that often triggered action potentials in dopamine neurons when the membrane potential was close to firing threshold. These fast potentials had a firing rate and pattern similar to that reported previously for extracellularly recorded dopamine neurons. Fast potentials were activated antidromically from the caudate nucleus at a latency similar to that reported for dopamine neurons, followed high frequency antidromic stimulation at a constant latency, and collided with spontaneously occurring fast potentials. Directly elicited action potentials would not collide reliably with antidromically activated fast potentials. Intracellular injection of depolarizing or hyperpolarizing current increased and decreased, respectively, the rate of occurrence of these potentials. The firing rate of fast potentials could be increased and decreased by the i.v. administration of dopamine antagonists and agonists, respectively. Simultaneous extracellular recording from pairs of DA neurons revealed numerous instances of synchronized action potentials. This was observed more frequently following i.v. haloperidol administration. Sets of burst firing dopamine neurons recorded simultaneously consistently demonstrated a decrease in the interspike interval as the burst progressed, a phenomenon commonly reported in other electrically coupled systems. Electrical coupling was suggested to be present in sets of identified nigrostriatal dopamine neurons. Electrical communication between these neurons could be involved in modulating burst firing and in synchronizing dopamine release.