Role of renal nerves in the hypotensive and the renal effects of atrial natriuretic factor in rats.Chin J Physiol. 1990; 33(1):5-18.CJ
Our earlier studies have demonstrated that atrial natriuretic factor (ANF) can produce hypotensive, natriuretic and diuretic effects and that changes in the renal nerve activity can alter the renal excretory function. A few previous studies suggested that ANF could change the renal nerve activity. Thus, the present study was designed to assess the role of the renal nerve in the natriuretic and diuretic effect of ANF. Experiments were conducted on four groups of anesthetized Sprague-Dawley rats: normal control rats, unilateral acute renal denervated rats with and without ANF administration and chronic renal denervated rats. The arterial blood pressure and the renal function responses to intravenous infusion of graded doses of ANF (atriopeptin III. 0.15, 0.30 and 0.45 microgram/kg.min) were studied. In normal rats, infusion of ANF significantly decreased the mean arterial blood pressure in a dose-related pattern (from 109 +/- 2 to 107 +/- 3, 102 +/- 4 and 89 +/- 5 mmHg, respectively). The glomerular filtration rate (GFR) did not change significantly whereas the urine flow and the absolute and the fractional excretion rates of sodium and potassium were significantly increased. Renal denervation alone did not change the blood pressure and GFR, but produced ipsilateral diuresis and saluresis without changing the function of the contralateral kidney. Subsequent administration of ANF decreased the blood pressure but did not affect bilateral GFR. There were significant increments in the urine flow and the excretions of sodium and potassium in both the denervated and the contralateral kidneys. Infusion of ANF into chronic renal denervated rats also reduced the blood pressure and increased the renal excretion of water and sodium. These results indicate that the diuretic and the natriuretic effects of ANF is not resulted from a decreased activity of the renal efferent nerve and that the hypotensive and the renal effects of ANF are independent of renal innervation.