乙酰胆碱、氨甲酰胆碱和γ-氨基丁酸对克氏原螯虾和日本沼虾尾足运动神经元的影响。

The effects of acetylcholine, carbamylcholine and gamma-aminobutyric acid on uropod motoneurons in the crayfish Procambarus clarkii and Cambaroides japonicus.

作者信息

Yoshino M, Masuda K, Hisada M

出版信息

Comp Biochem Physiol C Comp Pharmacol Toxicol. 1984;78(2):295-300. doi: 10.1016/0742-8413(84)90086-0.

Abstract

The effects of acetylcholine (ACh), carbamylcholine and gamma-aminobutyric acid (GABA) on the spike activity of uropod motoneurons were investigated electrophysiologically in the crayfish Procambarus clarkii Girard and Cambaroides japonicus de Haan. High concentrations of ACh were required to bring about an increase in the spike discharge of uropod motoneurons while carbamylcholine, which is not destroyed by cholinesterase, caused a marked increase in the motoneuron spike discharge even in low concentrations. Application of GABA in concentrations of 10(-5)-10(-2) M caused the decrease in the spike discharge of uropod motoneurons. Under the condition that the synaptic transmission onto uropod motoneurons was blocked by perfusing EGTA containing Ca2+-free saline with high-Mg2+, ACh increased the spike discharge of uropod motoneurons whereas GABA decreased it. The results suggested that ACh and GABA function as excitatory and inhibitory transmitters, respectively, in the crayfish central nervous system.

摘要

在克氏原螯虾（Procambarus clarkii Girard）和日本沼虾（Cambaroides japonicus de Haan）中，采用电生理学方法研究了乙酰胆碱（ACh）、氨甲酰胆碱和γ-氨基丁酸（GABA）对尾足运动神经元锋电位活动的影响。需要高浓度的ACh才能使尾足运动神经元的锋电位发放增加，而氨甲酰胆碱不受胆碱酯酶破坏，即使在低浓度下也能显著增加运动神经元的锋电位发放。应用浓度为10^(-5)-10^(-2) M的GABA可使尾足运动神经元的锋电位发放减少。在用含高镁离子的无钙生理盐水灌注EGTA阻断向尾足运动神经元的突触传递的条件下，ACh增加尾足运动神经元的锋电位发放，而GABA则使其减少。结果表明，在小龙虾中枢神经系统中，ACh和GABA分别作为兴奋性和抑制性递质发挥作用。