his study investigated the effect of electrical stimulation of the central end of cervical vagal nerve(CVN)on renal sympathetic nerve discharge (RSND)in 28 anesthetized rabbits. One of the common respons-es was an immediate increase of sympathetic efferent acthity and then followed by its complete complete cessation(308/365 exp).The average inhibitory time is 3.61±0.18s.The inhibition time of the CVN-RSND response could prolonged or shortened while the function of theCentral Nerve System were changed.Changes in the basal sympathetic tonic activity seem to contribute muchto the response when a vagal stimuls was applied

Whenever the based sympathetic tonic activity increased.the effect of CVN-RSND diminished.This mechannism play:an improtant role in the adaptation to the envi-ronmental requirments.