title: The dipsogen angiotensin II does not stimulate ethanol intake in mice.
abstract: Mice that were habituated to drinking ethanol solution and mice that had drunk water only (naive mice) were given an ICV infusion of angiotensin II (Ang II) at 2.9 ng/h for 8 days to determine the effect of chronic ethanol intake on the ingestive response to this potent dipsogen. Ang II infusion in alcohol-naive mice increased daily water intake from 3.7 +/- 0.2 ml (mean +/- SE, n = 6) to 11.0 +/- 1.5 ml on day 4 (p < 0.001) and to 18.3 +/- 2.6 ml on day 8 (p < 0.001). In subsequent experiments, mice had access to 4% ethanol solution up to day 4 and then to water for 4 days during the Ang II infusion. Alcohol-naive mice did not increase daily fluid intake until the water was provided on day 5; intake increased to 17.5 +/- 2.3 ml on day 8 (p < 0.001, n = 7). Mice accustomed to drinking 4% ethanol (4.3 +/- 0.3 ml/day) also did not increase intake until the water was provided; intake reached 22.9 +/- 3.0 ml of water on day 8 (p < 0.001, n = 7). Mice accustomed to drinking 10% ethanol behaved similarly (n = 4). Thus, alcohol-naive or -habituated mice did not respond to this dipsogenic stimulus until water was available; the thirst for water was unimpaired. Preference-aversion tests showed that mice drank little or no 4% ethanol (or even 2% ethanol) when water was also available. Taste aversion, plus previous experience from ingestion of ethanol in habituated mice, may explain the rejection of ethanol to quench Ang II-induced thirst. Experimental results obtained using other aversive solutions, 3 mM quinine and 300 mM KCl, suggest that postingestional, metabolic effects of solutes may also contribute to such rejection.
authors.affiliation: Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: J R
authors.initials: JR
authors.lastname: Blair-West
authors.forename: D A
authors.initials: DA
authors.lastname: Denton
authors.forename: M I
authors.initials: MI
authors.lastname: McBurnie
authors.forename: R S
authors.initials: RS
authors.lastname: Weisinger
mesh_terms: D000428:Alcohol Drinking / Q000523:psychology*; D000804:Angiotensin II / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D004327:Drinking Behavior / Q000187:drug effects*; D004435:Eating / Q000187:drug effects; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011189:Potassium Chloride / Q000494:pharmacology; D011803:Quinine / Q000494:pharmacology; D013649:Taste / Q000187:drug effects
chemical_list: D000804:Angiotensin II; D011189:Potassium Chloride; D011803:Quinine