Thirst and sodium appetite in Dahl rats.
In confirmation of a previous study, rats of the Dahl S and R sublines exhibited no spontaneous preference for dilute NaCl solutions and an aversion for isotonic and hypertonic NaCl solutions when they were offered in a 2-bottle choice with water. A hysteresis effect was observed when choice was offered between water and a descending series of concentrations of NaCl solution compared with a preceding increasing series. In response to either chronic dietary administration of an angiotensin I converting enzyme inhibitor (ACEI) or acute sodium depletion, rats of the R subline developed a strong NaCl appetite, but the S subline did not. In contrast, rats of both sublines showed an NaCl appetite in response to a regimen of deoxycorticosterone acetate (DOCA). In acute drinking tests, rats of the S subline drank less water than those of the R subline in response to administration of either isoproterenol, ACEIs, or hypovolemia. Both R and S sublines drank similar amounts of water after SC administration of angiotensins I and II, and hypertonic NaCl. Compared with R rats, S rats had lower plasma renin activity in several of the above conditions, and their decreased thirst and sodium appetite appears to be a direct result of an underactive renin-angiotensin system.
Rowland
N E
NE
Department of Psychology, University of Florida, Gainesville 32611.
Fregly
M J
MJ
D000818:Animals; D001066:Appetite / Q000502:physiology*; D005260:Female; D005518:Food Preferences / Q000502:physiology*; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012084:Renin-Angiotensin System / Q000502:physiology; D012462:Saline Solution, Hypertonic / Q000008:administration & dosage*; D013894:Thirst / Q000502:physiology*; D014882:Water-Electrolyte Balance / Q000502:physiology*
D012462:Saline Solution, Hypertonic; D007703:Peptidyl-Dipeptidase A