Effects of intracerebroventricular infusion of angiotensin Ii and related peptides on water and sodium ingestion and excretion
Gonçalves, J.R.; Camargo, L.A.; Menani, J.V.; Saad, W.A.; Saad, W.A.; Renzi, A.; De Luca Júnior, L.A.
Brazilian Journal of Medical and Biological Research 21(3): 615-619
1988
ISSN/ISBN: 0100-879X PMID: 3228647 Document Number: 321697
The objective of the present study was to investigate the effects of an angiotensin II (AII) analogue, Des-Asp1-AII and of two competitive blockers, [Leu8]-AII and [octanoyl-Leu8]-AII, infused intracerebroventricularly on the ingestion of water and of a 3% NaCl solution, as well as on diuresis and natriuresis in normal rats and in adrenalectomized and deoxycorticosterone (DOCA)-treated rats. Both AII and Des-Asp1-AII increased water and 3% NaCl intake and increased urine and Na+ excretion, the effect of AII being more intense. Except for 3% NaCl, the responses of all other parameters were totally or partially reduced by previous treatment with [Leu8]-AII or [octanoyl-Leu8]-AII. Subcutaneous DOCA injection caused water ingestion. Previous treatment with DOCA increased the response to AII for the ingestion of 3% NaCl and inhibited sodium excretion. The results obtained for adrenalectomized rats treated with DOCA, AII and analogous agonists did not differ from those observed in normal rats. These data suggest a possible synergism between the cerebral and renal renin-angiotensin systems in the regulation of the physiological parameters studied.