Water balance effects of systemic and intracerebroventricular administration of angiotensin II in the toad Bufo arenarum

JUAN C. REBOREDA; SEGURA, E. T.

Comparative Biochemistry and Physiology. A: Comparative Physiology

Año: 1989 vol. 93 p. 505 - 509

0300-9629

Systemic administration of angiotensin II (10 µg/kg) to fully hydrated toads decreased urine production but did not affect natripheric or hydrosmotic water fluxes across the skin. 2. The antidiuretic response was not modified by the simultaneous α-adrenergic blocking with tolazoline (5 mg/kg). 3. In a similar way, single intracerebroventricular injections of 1 µl10-4M angiotensin II, decreased urine production but did not affect water uptake. 4. Finally, systemic injections of the angiotensin blocker salarasin (100 µg/kg) did not affect the cutaneous hydrosmotic response of dehydrated toads. 5. We conclude that angiotensin II has no effects on water uptake in this species. The antidiuretic response to angiotensin II, and the involvement of adrenergic mechanisms are discussed.