摘要
目的探讨海洛因依赖对大鼠背侧海马神经元功能以及海马谷氨酸(Glu)和γ-氨基丁酸(GABA)递质系统的影响。方法按剂量逐日递增原则,1日2次,连续9 d皮下注射海洛因建立其依赖SD大鼠模型。采用玻璃微电极细胞外记录大鼠海马神经元自发放电,比较放电形式和频率的变化。并用氨基酸自动分析仪测定大鼠海马Glu和GABA含量。结果海洛因依赖组大鼠背侧海马神经元放电以中频(51.02%)、单个不匀(61.22%)为主,对照组则以低频(58.70%)为主,形式分布均一(P<0.05);海洛因对腹侧海马神经元放电无影响(P>0.05);依赖大鼠海马Glu含量下降,GABA含量增加(P>0.05),Glu/GABA比值低于对照组(P<0.05)。结论海洛因更易损伤大鼠背侧海马神经元功能;Glu/GABA递质系统的紊乱可能是海洛因损害大鼠学习记忆能力的机制之一。
Aim To study the impact of heroin on the function of the dorsal hippocampus neurons, and determine the content of glutamate (Glu) and gamma-aminobutyric acid (GABA) and their content ratio in the hippocampus of rats. Methods Heroin was injected subcutaneously twice a day for 9 days according to the principle of daily increasing dose in the heroin-dependent Sprague-Dawley rats. The unit discharges of the hippocampus neurons were observed in rats by the extracellular single-unit recording with glass microelectrodes. Besides,the content of glutamate and gamma-aminobutyric acid in the hippocampus of other rats was measured with the amino-acid automatic analysis apparatus. Results The spontaneous discharges of the dorsal hippocampus in the dependent rats were primarily middle frequency ( 1 ~ 10 Hz,51.02% ) and single,irregular discharge form ( 61.22% ) , whereas low frequency ( 〈 1Hz, 58.70%) and equal ratio of three discharge forms was found in the control group (P 〈 0.05). The discharge of ventral hippocampus neurons was unaffected by heroin (P 〉 0. 05 ). There was a decreasing trend in the content of glutamate and an increasing trend in that of gamma-aminobutyric acid in the hippocampus although there was no significant difference between two groups (P 〉 0. 05 ) , the content ratio of glutamate to gamma-aminobutyric acid in the hippoeampus of the dependent rats was lower than that in the control group ( P 〈 0.05 ). Conclusions The dorsal hippocampus of rats is highly vulnerable to damage from heroin. The disorder of the Glu/GABA neurotransmitters in the hippocampus caused by heroin may be one of the mechanisms impairing the learning and memory of rats.
出处
《中国药理学通报》
CAS
CSCD
北大核心
2009年第5期646-649,共4页
Chinese Pharmacological Bulletin
基金
贵州省优秀科技教育人才省长专项基金资助项目(No黔科教办〔2001〕3号)
关键词
海洛因
海马
单位放电
谷氨酸
Γ-氨基丁酸
heroin
hippocampus
unit discharges
glutamate
gamma-aminobutyric acid