Effect of beta-adrenergic block on the response of plasma renin activity to acute sodium depletion in the rabbit
Iacobelli, A.; Maceroni, P.; Fontana, O.; Vecci, E.; Cavallotti, C.
Bollettino della Societa Italiana di Biologia Sperimentale 51(18): 1133-1139
1975
ISSN/ISBN: 0037-8771 PMID: 1220728 Document Number: 84177
Rabbits were injected i.v. with furosemide. Blood samples were taken to determine basal and post-treatment plasma renin activity (PRA). Urine samples were also taken for urinary Na excretion values. After a wk's rest, the rabbits were subjected to the same experiments after intragastric administration of oxprenolol, 4 times at 8 h intervals. Blood samples were taken as before. The natriuretic effect of furosemide after oxprenolol showed the effects of stress. The response of the renin-angiotensin system was reduced in the presence of acute Na depletion. The hypothesis is formulated that water and salt depletion activates renin secretion due to changes in plasma volume, or possibly due to changes in the intratubular Na content. Increased renin secretion is probably mediated by the intrarenal sympathetic nerves. The effects of .beta.-adrenergic block with oxprenolol confirms the theory that the control of renin secretion in response to Na depletion is mediated by .beta.-adrenergic receptors.