Effects of intracerebroventricular infusion of angiotensin II and related peptides on water and sodium ingestion and excretion.
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.
Gonçalves
J R
JR
Departamento de Ciências Fisiológicas, Faculdade de Odontologia de Araraquara, UNESP, SP, Brasil.
Camargo
L A
LA
Menani
J V
JV
Saad
W A
WA
Saad
W A
WA
Renzi
A
A
De Luca Júnior
L A
LA
D000315:Adrenalectomy; D000804:Angiotensin II / Q000031:analogs & derivatives* / Q000494:pharmacology; D000805:Angiotensin III / Q000494:pharmacology*; D000818:Animals; D003900:Desoxycorticosterone / Q000627:therapeutic use; D004231:Diuresis / Q000187:drug effects*; D004326:Drinking / Q000187:drug effects*; D007276:Injections, Intraventricular; D008297:Male; D009318:Natriuresis / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012965:Sodium Chloride / Q000378:metabolism
D000804:Angiotensin II; D000805:Angiotensin III; D003900:Desoxycorticosterone; D012965:Sodium Chloride; C014622:angiotensin II, Ile(8)-