谷氨酸、γ-氨基丁酸及其拮抗剂对大鼠旁巨细胞外侧核神经元自发放电的影响  

Effects of L Glutamic Acid, γ aminobutyric Acid and Their Respective Antagonists[KG*4/5〗on[KG*4/5〗Spontaneous[KG*4/5〗Discharge[KG*4/5〗of[KG*4/5〗Nucleus Paragigantocellularis Lateralis Neurons in Rats

作　　者：李莉华[1] 郑煜[1] 徐美丽 

机构地区：[1]基础医学院生理学教研室

出　　处：《华西医科大学学报》1997年第1期31-36,共6页Journal of West China University of Medical Sciences

基　　金：国家自然科学基金

摘　　要：采用多管微电极技术在２２只麻醉的ＳＤ大鼠观察了分别微电泳谷氨酸钠（Ｌ－Ｇｌｕ）、γ－氨基丁酸（ＧＡＢＡ）及其拮抗剂ＤＬ－２－氨基－５－磷酸戊酸（ＡＰ５）、荷包牡丹碱（ＢＩＣ）对旁巨细胞外侧核尾半侧（ｃＰＧＣＬ）神经元自发放电的效应和ＡＰ５对Ｌ－Ｇｌｕ，ＢＩＣ对ＧＡＢＡ作用的影响。结果显示：Ｌ－Ｇｌｕ使大多数被测试神经元（３０／３６个）兴奋，ＧＡＢＡ使全部受试神经元（ｎ＝５３）抑制；ＡＰ５、ＢＩＣ有兴奋、抑制和无作用三类效应，Ｌ－Ｇｌｕ和ＢＩＣ的兴奋作用、ＧＡＢＡ的抑制作用呈量效依赖关系；ＡＰ５部分阻断大部分受试神经元（１４／１９个）对Ｌ－Ｇｕ的兴奋反应，ＢＩＣ部分或完全阻断大多数受试神经元（１８／２４个）对ＧＡＢＡ的抑制反应，提示ｃＰＧＣＬ可能存在起神经递质作用的内源性Ｌ－Ｇｌｕ和ＧＡＢＡ及兴奋性氨基酸（ＥＡＡ，包括ＮＭＤＡ和非ＮＭＤＡ）受体和ＧＡＢＡＡ受体。这些递质和受体可能介导ＰＧＣＬ对呼吸和其它机能系统的调控。Using multibarrel microelectrode techniques, we studied the effects of iontophoretic application of L glutamic acid (L Glu), γ aminobutyric acid (GABA) and their respective antagonists DL 2 amino 5 phosphonovaleric acid (AP5), bicuculline(BIC) on the spontaneous discharge of the caudal half of nucleus paragigantocellularis lateralis(cPGCL) neurons(including respiratory related neurons) and the influences of AP5 and BIC on the effects of L Glu and GABA respectively in 22 anesthetized spontaneously breathing Sprague Dawley rats. The spontaneous discharges of all the cPGCL neurons tested were inhibited by GABA( n =53). Most of the tested neurons were excitated by L Glu(30/36). AP5 and BIC both showed three kinds of effects on the cPGCL neuronal spontaneous discharge: excitatory, inhibitory and no effect. The excitatory effects of L Glu and BIC and the inhibitory effects of GABA showed a dose response relationship. AP5 could block partially the excitatory effect of L Glu on a large part of neurons tested (14/19). BIC blocked, partially or completely, the inhibitory effect of GABA also on a large part of the neurons tested(18/24). The results implicate that there might exist endogenous L Glu and GABA acting as neurotransmitters in the cPGCL area and excitatory amino acids (EAA, including NMDA and non NMDA) and GABA receptors on cPGCL neurons. These neurotransmitters and receptors may mediate the regulatory action of cPGCL on respiration and other functional systems.

关 键 词：旁巨细胞外侧核 神经元 自发放电 谷氨酸 GABA 

分 类 号：R338[医药卫生—人体生理学]