大鼠楔状核内微量注射吗啡、乙酰胆碱对中缝大核痛放电的影响  

Effects of Morphine and Acetylcholine Microinjected into Nucleus Cuneiformis on the Evoked Discharges of Pain Excitation Neurons in Nucleus Raphe Magnus of the Rat

作　　者：李韶[1] 张自东[2] 吴晓平[2] 

机构地区：[1]滨州医学院生理学教研室,山东滨州256603 [2]同济医科大学基础医学院生理学教研室

出　　处：《同济医科大学学报》1994年第1期11-14,共4页Acta Universitatis Medicinae Tongji

摘　　要：用玻璃微电极细胞外记录神经元放电与脑核团注药方法，观察大鼠楔状核内微量注射吗啡、乙酸胆碱对中缝大核内痛兴奋性神经元痛放电频率的影响。结果表明；向楔状核分别注入吗啡和乙酰胆碱均能抑制中缝大核的痛放电；若预先向楔状核注射纳络酮和阿托品能分别拮抗吗啡及乙酰胆碱的抑制痛放电效应。单独注入纳络酮或阿托品可引起痛放电频率增加。结果提示：楔状核内某些神经元对中缝大核的痛兴奋性神经元活动起抑制作用，楔状核内的内源性阿片肽与乙酰胆碱参与这一过程，并分别由阿片受体及胆碱能M-受体介导。Recent evidence points to a possible role for the nucleus cuneiformis (NCF) in influencing activity of nucleus raphe magnus (NRM). We used extracellular recording to investigate the effect of morphine or ACh injected into NCF on the frequencies of evoked dis charge of pain excitation neurons (PEN) in NRM of the rat. The results were as follows:1 ) Intra-NCF injection of morphine (5 μg/0.5 μl, n=8)or ACh (2.5μg/0.5μl, n=9) could suppress the frequencies of evoked discharge of PEN in NRM (P＜0.01 or ＜0.05), the maximal inhibition rate being 78.4±7.0% and 77.6±9.0% respectlvely. 2) The above mentioned inhibitory effect of morphine or ACh could be antagonlzed by Intra-NCF preinjec tion of naloxone (P＜0.001,n=8) and atropine (P＜O.001, n=9) respectively.3 ) Naloxone (l μg/0.5μl, n=8) or atropine (2.5μg/0.5μl,n=8)injected into NCF could enhance the evoked discharges of PEN in NRM (P＜0.01, 0.05), the percentage of change in the fre quency of evoked discharge Increased by 82.9±4.1 % and 46.0±14.3% respectively. These findings suggest that some NCF neurons may modulate nociceptive transmission via choliner glc and opioid mechanism, and that above-mentioned inhibitory effect may be mediated by cholinergic receptor or opioid receptor.

关 键 词：楔状核 中缝大核 痛兴奋性 神经元 

分 类 号：R322.81[医药卫生—人体解剖和组织胚胎学]