Intracerebroventricularly infused angiotensin II or III do not alter voluntary alcohol intake in rats.
Subcutaneous injections of angiotensin (ANG) II or III in the periphery reduce alcohol intake and raise water intake. These peptides do not cross the blood-brain barrier and cannot reach the angiotensin receptor-rich sites surrounding the lateral and third ventricles. To examine the effect on alcohol intake of ANG II and III at these ventricular sites, groups of rats were first trained to drink alcohol using a limited access procedure, then surgically prepared with chronic indwelling lateral or third ventricular cannulae, and then reoffered daily 40-min access to alcohol. Neither ANG II (25-200 ng) nor ANG III (25-100 ng) had any effect on alcohol consumption at either of the two ventricular sites. Water consumption was significantly enhanced by both peptides at both sites and could be attenuated by prior treatment with the ANG II antagonist Sar1Thr8-ANG II. The SC administration of ANG II was able to produce a significant reduction in alcohol drinking. These findings demonstrate that ICV administered ANG II or ANG III do not modulate alcohol drinking and that changes in alcohol intake do not result from the thirst promoted by ANG II. Sites in the periphery may be more involved in the interaction between angiotensin and alcohol consumption.
Grupp
L A
LA
Primary Mechanisms Department, Addiction Research Foundation of Ontario, Toronto, Canada.
Harding
S
S
D000428:Alcohol Drinking / Q000523:psychology*; D000804:Angiotensin II / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000805:Angiotensin III / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D004326:Drinking / Q000187:drug effects; D007276:Injections, Intraventricular; D007279:Injections, Subcutaneous; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D000804:Angiotensin II; D000805:Angiotensin III; C014805:angiotensin II, Sar(1)-Thr(8)-