Endogenous renin-angiotensin system and drinking behavior in flounder.
High rates of drinking in seawater-adapted, compared with freshwater (FW)-adapted, flounder were associated with raised plasma chloride and osmotic concentrations. Hypotension in FW-adapted fish, after papaverine administration, gave rise to greatly elevated rates of drinking. This dipsogenic response apparently relied on activation of the endogenous renin-angiotensin system (RAS) and was abolished by simultaneous administration of the converting enzyme inhibitor, captopril. Exogenous angiotensin II was shown to be dipsogenic and vasopressor in the FW-adapted fish. The physiological importance of the activation of the RAS in the control of drinking behavior in euryhaline fish is discussed.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002216:Captopril / Q000494:pharmacology; D004326:Drinking / Q000187:drug effects; D004327:Drinking Behavior / Q000502:physiology*; D005399:Fishes; D005618:Fresh Water; D010208:Papaverine / Q000494:pharmacology; D012084:Renin-Angiotensin System; D012462:Saline Solution, Hypertonic; D012623:Seawater
D012462:Saline Solution, Hypertonic; D002216:Captopril; D010208:Papaverine