To examine the role of the renal nerves in the increased plasma renin activity (PRA) of sodium depletion, two protocols were used. In protocol I (five dogs), PRA increased significantly with sodium depletion both before and after bilateral renal denervation and the responses did not differ (P < .05). In protocol 2 (five dogs), PRA increased (P < .005) with sodium depletion and remained elevated for 8 days after renal denervation (P < .05); however, PRA declined slightly from the predenervation values for PRA (P < .05). Five other dogs were studied similarly following sham denervation; a similar progressive decline in PRA occurred after sham denervation (P < .05). Direct measurement of renin secretion in four sodium depleted, renal denervated dogs and in five normal dogs demonstrated higher values in the sodium depleted animals (P < .005). Intrarenal arterial infusion of papaverine had no effect on renin secretion in normal dogs, but decreased renin secretion in sodium depleted dogs (P < .05). It is concluded that the increased renin secretion during sodium depletion in not dependent on intact renal nerves, but appears to be dependent on a renal vascular receptor.
ASJC Scopus subject areas
- Physiology (medical)