过刊浏览

刺激交感神经对大鼠多觉型伤害性感受器诱发和自发放电的不同作用

胡三觉, 陈敏, 田巧莲, 张淑洁

第四军医大学生理教研室. 陕西；中国科学院上海生理研究所. 上海

摘要

多觉型伤害性感受器是皮肤内专一性较强的痛觉感受器。该实验用剥制神经细束的技术,引导大鼠尾神经C类纤维的传入放电反映多觉型伤害性感受器的活动,以判定刺激交感神经对外周痛觉感受过程的调制作用。测试了57个该类感受器的单位放电,发现下述两个主要事实:(1)刺激腰骶部交感干外周端,可以显著抑制伤害性刺激(包括机械压力,直流电-钾离子,热烫等)诱发的多觉型伤害性感受器的单位放电,其作用出现较快,可使放电数减少1/3左右,后作用延续十多分钟。局部动脉注射去甲肾上腺素也产生类似的抑制效应。从而证实交感神经具有抑制痛觉感受器的作用。

关键词： 多觉型伤害性感受器; 诱发单位放电; 自发单位放电; 伤害性刺激; 腰骶交感; 神经干; 双重作用

Different effects of sympathetic stimulation on evoked and spontaneous discharges of the polymodal nociceptors in rat

Hu Sanjue, Chen Min, Tian Qiaolian, Zhang Shujie

Department of Physiology, the Fourth Military Medical College. Xian, Shaanxi, China；Shanghai Institute of Physiology, Academia Sinica. Shanghai, China

Abstract

In the present study the tail nerve in rat was dissected of small bundles of fibers and unit discharges of afferent C fibers evoked by noxious stimuli such as mechanical pressure and direct current potassium iontophoresis and heat were recorded. The unit discharges were used as indices of activity of the polymodal nociceptors, the specialized pain receptors in skin, to investigate the modulating effects of sympathetic nerve on peripheral sensation process of pain. 57 units of the polymodal nociceptors were studied, the following two main facts were found. (1) Stimulation of the peripheral end of the cat lumbosacral sympathetic trunk could inhibit markedly the unit discharges of the polymodal nociceptors evoked by noxious stimuli. The inhibitory effect occurred quickly and caused the number of unit discharges to decrease about one-third. The after effect lasted for more than ten min. Injection of norepinepherine into the tail artery had a similar inhibitory effect. This finding confirmed our previous report that the sympathetic nerve possessed an inhibitory effect on pain receptors. (2) The modulating effect of sympathetic stimulation on the activity of parts of the polymodal nociceptors showed a dual nature, namely, it inhibited the evoked discharges but facilitated the spontaneous discharges of the same unit. Based on these results, it was suggested that abnomality of the dual effect of the sympathetic nerve on the polymodal nociceptors might be one of the causes producing causalgia and an assumption that acupuncture might modulate the peripheral sensation process of pain via the sympathetic nerve was discussed.

Key words: Polymodal nociceptors;Evoked unit discharges;Spontaneous unit discharges;Noxious stimulation;Lumbosacral sympathetic trunk;Dual effects;

收稿日期：　　录用日期：

通讯作者：　　E-mail:

引用本文：

胡三觉, 陈敏, 田巧莲, 张淑洁. 刺激交感神经对大鼠多觉型伤害性感受器诱发和自发放电的不同作用[J]. 生理学报 1986; 38 (3): .

Hu Sanjue, Chen Min, Tian Qiaolian, Zhang Shujie. Different effects of sympathetic stimulation on evoked and spontaneous discharges of the polymodal nociceptors in rat. Acta Physiol Sin 1986; 38 (3): (in Chinese with English abstract).