Involvement of medulary tail-flick related neurons in descending facilitation evoked by chemical stimulation of rat lateral habenular nucleus  

Involvement of medullary tail flick related neurons in descending facilitation evoked by chemical stimulation of rat lateral habenular nucleus

作　　者：黄洛秀[1] 程珍凤[2] 

机构地区：[1]复旦大学生理学与生物物理学系立人实验室 [2]西安医科大学生理学教研室

出　　处：《中国药理学报》1998年第1期20-23,共4页Acta Pharmacologica Sinica

摘　　要：研究外侧缰核内微量注射Ｌ谷氨酸钠对大鼠延髓甩尾相关神经元活动和甩尾反射的影响．方法：用辐射热烫尾并同步记录延髓头端腹内侧区神经元单位放电和甩尾反射．结果：外侧缰核内微量注射Ｌ谷氨酸钠可加强给型甩尾相关细胞自发放电，抑制撤型甩尾相关细胞的自发放电，两类细胞的自发放电率分别从注射前的５８±２２Ｈｚ和１１．８±２２Ｈｚ变为注射后的１０９±３４Ｈｚ和６１±２２Ｈｚ．同时易化了两类细胞的甩尾相关反应和伤害剌激引起的甩尾反射，甩尾反射潜伏期从注射前的４０４±０１７ｓ缩短为注射后的２９７±０１３ｓ．结论：外侧缰核对节段性防御反射有下行易化作用，这种易化作用是通过延髓内撤型和给型甩尾相关细胞的协同活动而实现的．AIM: To study effects of sodium L glutamate microinjection into lateral habenular nucleus (LHN) of rats on the firing of medullary tail flick related neurons and tail flick reflex (TF). METHODS: Using synchronous recording of unitary neuronal discharges and TF induced by noxious heat. RESULTS: Chemical stimulation of LHN induced an excitement of the on cell spontaneous activity, an inhibition of the off cell spontaneous activity with an enhancement of their TF related responses. The spontaneous firing rate of on cells increased from 5 8±2 2 Hz to 10 9±3 4 Hz while the spontaneous firing rate of off cells decreased from 11 8±2 2 Hz to 6 1±2 2 Hz. Meanwhile the TFL was shortened from 4 04±0 17 s to 2 97±0 13 s. CONCLUSION: The chemical stimulation of LHN produced a facilitating action on nociceptive spinal defensive reflex. This effect is brought out by the cooperation of on and off cells.

关 键 词：缰核 谷氨酸钠 延髓 神经元 痛 测定 

分 类 号：R338.1[医药卫生—人体生理学] R441.1[医药卫生—基础医学]