楔状核内TRH抗伤害感受机制的探讨(英文)  

Ivestigation of the antinociceptive mechanism of TRH in nucleus cuneiformis

作　　者：李韶[1] 孙长凯[1] 李冬冬[1] 张万琴[1] 

机构地区：[1]大连医科大学生理学教研室,辽宁大连116027

出　　处：《中国神经科学杂志》2002年第4期668-672,677,共6页

摘　　要：用玻璃微电极细胞外记录结合核团微量注射的方法 ,于延髓中缝大核 (NRM )内记录痛兴奋神经元(PEN)的单位放电 ,探讨楔状核 (NCF)内促甲状腺素释放激素 (TRH)抗伤害感受作用的机制。结果表明 :NCF内注射TRH能明显抑制PAG及NRM内PEN痛放电 ,NCF或PAG内预先注射纳洛酮 (1μg/0 .5 μL)能部分阻断NCF内TRH对NRM及PAG内PEN痛放电抑制效应。提示 :TRH在NCF内的抗伤害感受作用可能与阿片受体有关。其机制有可能通过下行镇痛单突触或多突触通路实现。By using the extracellular recording with microinjection of nucleus method, the frequencies of evoked discharge of pain excitation neurons (PEN) of nucleus raphe magnus (NRM) and mesencephalic periaquductal gray (PAG) to investigate the mechanism of the antinociceptive role of thyrtropin releasing hormone (TRH) in nucleus cuneiformis (NCF) were recorded.The results are as follows: 1. Intra NCF injection of TRH (0.5 μg/0.5 μL, n =12) could suppress the frequencies evoked discharge of PEN in NRM and PAG ( P <0.001,0.01,0.05), the maximal inhibitory rate was 71.2%±5.9% and 74.2%±8.0% respectively. 2. Naloxone (NX) (2.5 μg/0.5 μL) preinjected into NCF could antagonize TRH's inhibitory action on the evoked discharge of PEN in NRM, while atropine preinjected into NCF could not influence it significantly. 3. Naloxone (5 μg/0.5 μL) preinjected into PAG could antagonize the inhibitory action of TRH injected into NCF on the evoked discharge of PEN in NRM. These findings suggest that some neurons in NCF might participate in the modulation of noxious information transmission in CNS and PAG NRM pathway was at least in part involved. TRH might be a neuromodulator or transmitter in the antinociception of NCF.

关 键 词：楔状核 中缝大核 中脑导水管周围灰质 TRH 痛调制 促甲状腺素释放激素 NCF 

分 类 号：R338.2[医药卫生—人体生理学]