电生理学特性得到确定的大鼠脊髓背根神经节细胞内谷氨酸和P物质的共存
杨鲲, 王过渡, 李云庆, 施际武, 赵志奇
第四军医大学基础部解剖学教研室;中国科学院上海脑研究所
摘要
在离体灌流带脊髓和坐骨神经的标本上,对脊髓背根神经节(DRG)细胞的电生理学特性、对P物质(SP)受体激动剂的反应及谷氨酸(Glu)/SP共存的特点进行了研究。(1)对135个细胞进行了细胞内记录,并依纤维传导速度将其分为Aα/β(>12m/s)和C(<1.3m/s)两大类;它们的动作电位的快速后超极化(fAHP)有明显区别,C类的fAHP幅度小、时程长,Aα/β类的fAHP幅度大、时程短;(2)SP受体激动剂Sar-SP(10-6mol/L)诱导42%(5/12)的Aα/β细胞和80%(8/10)的C细胞发生去极化反应;(3)最后向给予SP受体激动剂的22个细胞内电泳biocytin,固定、切片后进行磷酸激活的谷氨酰胺酶(PAG)和SP免疫荧光组织化学染色并同时显示biocytin,观察到biocytin标记并呈PAG样和SP样阳性的三标细胞在Aα/β类为25%(3/12),C类为80%(8/10),两者差异显著(P<0.05)。结果提示DRG中Aα/β细胞与C细胞的化学解剖和电生理特性不同,SP可能通过作用于节细胞上的自身受体易化冲动的发放。
关键词: 背根神经节; 细胞内记录; 细胞内标记; 递质共存; 免疫荧光多重染色; 大鼠
Cui Hong
First Clinical Institute,China Medical University. Shenyang 110001,Liaoning, China
Abstract
Electrophysiological properties, reaction to sustance P (SP) receptor agonist, and co-existence of glutamate (Glu) and SP in neurons of the spinal dorsal root ganglion (DRG) of the rat were investigated in vitro.The main results were: (1) According to the fiber conduction velocity, totally 135 intracellularly recorded DRG neurons were divided into Aα/β type(> 12m/s) and C type (<1.3 m/s). There were remarkable differences between the fast afterhyperpolarization (fAHP) of action potential between the two types:fAHP of C type neurons had smaller amplititude and longer duration, whereas the fAHP of Aα/β type neurons had larger amplititude and: shorter duration. (2) Among 22 DRG neurons of which overshoots of action. protential appeared, specific SP receptor agonist Sar-SP induced depolorization in 42% (5/12) of the Aα/β type neurons and 80% (8/10)of the C type neurons. (3) Biocytin was intracellularly injected into the 22 Sar-SP administrated DRG neurons.
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引用本文:
杨鲲, 王过渡, 李云庆, 施际武, 赵志奇. 电生理学特性得到确定的大鼠脊髓背根神经节细胞内谷氨酸和P物质的共存[J]. 生理学报 1998; 50 (4): .
Cui Hong. . Acta Physiol Sin 1998; 50 (4): (in Chinese with English abstract).