小肠渗透压感受器对肾交感神经传出电活动的调节作用

Role of Small Intestine Osmositive Vagal Receptors in Regulation of Renal Sympathetic Efferent Nerve Activity

阐明肾交感神经在抗利尿效应中所起的作用。对乌拉坦和氯醛糠混合液麻醉的Wistar 大鼠和猫,用3.2%氯化钠高渗盐水灌流小肠,观察到肾交感神经传出冲动显著增加,与灌流前的冲动频率相比,差异有非常显著意义(P<0.001);用等量生理盐水灌流前后,肾神经传出冲动则无显著变化,可是,先在隔下切断两侧迷走神经后再进行高渗盐水灌流,上述反射作用即不再出现。实验结果提示,小肠渗透压感受器兴奋,可反射性地增加肾交感神经的传出冲功。实际上,早已有文献报道,肾交感神经可直接作用于肾小管,促进钠和水的重吸收;因此,肾交感神经可能是上述抗利尿反射效应的传出途径。

Under anaesthesia(ureth- ane 500～800mg/kg and chloralose 40～ 70 mg/kg),renal sympathetic efferent nerve(RSEN)activities were observed in Wistear rats and cats.An increase in RSEN activity was observed follo- wing intstinal perfusion with hyper- tonic NaCl solution(1.6% and 3.2%) in normal preparation.However,no effect in RSEN activity was observed following intestinal perfusion with isotonic saline.In the subdiaphragm- atically vagotomized animals no change in RSEN activity was observed follo- wing perfusion by hypertonic NaCl solution.The results suggest the exis- tence of reflex pathway from intesti- nal vagal afferent osmoreceptore to RSENs,the hypertonic stimulation of the intestine facilitates RSEN activity through this reflex system,and resu- lts in antidiuresis due to the probable influence of renal tubular reabsorption of sodium and water.