小肠机械感受器对内脏神经传出电活动的调节作用  

Reflex Effects of Intestinal Mechanoreceptors on Splanchnic Nerve Activity

作　　者：蒋正尧[1] 姜如冈[1] 李楚芬[1] 

机构地区：[1]宁夏医学院生理学教研室,天津医学院生理学教研室

出　　处：《宁夏医学杂志》1994年第2期69-72,共4页Ningxia Medical Journal

摘　　要：通过置入小肠的气囊机械地扩张肠管，在２３只麻醉家兔中观察到小肠机械感受器兴奋的传入冲动引起内脏神经传出放电活动减少，出现短暂的电寂静期。抑制效应持续２～３秒，而且无论“给刺激”和“撤刺激”均可诱发出类似的抑制效应；稳态的持续扩张刺激则无效，而表现出“小肠快适应型机械感受器”兴奋的特征。颈部切断两侧迷走神经不能消除上述抑制效应——一种“交感一交感神经反射”；横切脑干实验表明：只要保持延髓和脊髓的完整，该抑制效应的性质不变，提示反射的中枢部位可能在延髓。Experiments were per-formed on 23 rabbits anaesthetized with sodium pentobarbital,The animals were immobilized with flaxedil and artificially ventilated,Multi-unitbefferent discharges of splanchnic fi-ers were recorded.A balloon in the.small intestine was inflated with 10～15ml air,associated with suddem distention,a reflex suppression in the efferent discharges could beseen,lasting for 2～3 s,giving `on`and `off` responses when the mechanical stimulus was applied and later rermo-ved,but giving no response while the stimulus was held steady.This res-ponse was not affected by bilateral vagotomy.It is concluded that,the rapidly adapting mechanoreceptors of the intestine exert a reflex inhibitory effect on the efferent discharges of splanchnic fibers,utilizing the Latters`sympathetic,small path-ways as their both afferent & efferentlimbs.

关 键 词：小肠 机械感受器 内脏神经 放电 

分 类 号：R338.8[医药卫生—人体生理学]