The effect of efferent discharges in renal nerves on the activity of arterial mechanoreceptors in the kidney in rabbit.

1. The effect of sympathetic efferent flow in renal nerves on afferent discharges from renal arterial mechanoreceptors was observed in dissected filaments of renal nerves in the rabbit.2. An increase in afferent discharge rate was observed after renal nerve stimulation.3. Perfusate accumulated during renal nerve stimulation in an isolated kidney preparation showed a vasoconstrictor effect on blood vessels in rabbit ear.4. Infusion of a small amount of (+/-)-noradrenaline increased afferent discharge rate.5. Modification of blood pressure levels by chemical means modified renal afferent discharge rate.6. It is suggested that there is an efferent control mechanism on the activity of renal arterial mechanoreceptors by a vasomotor reflex.