Chronic treatment with ethanol produces supersensitivity to oxotremorine.
1. The effect of chronic treatment with ethanol (14% v:v in drinking water) on the physiological endpoint core temperature which is partially regulated by a muscarinic mechanism was measured in adult male rats (n = 8). 2. One and two weeks of treatment were associated with enhancement of the hypothermic response to oxotremorine, 0.25 mg/kg ip (p = 0.0005 and p = 0.0001, respectively). 3. The sample remained supersensitive to this muscarinic agonist 48 and 96 hours after the discontinuation of treatment (p = 0.0014 and p = 0.013 respectively). 4. Repeated injections of oxotremorine, 0.25 mg/kg ip, every other day for 10 days did not produce carry-over effects in a control experiment. 5. The results suggest that ethanol renders muscarinic mechanisms supersensitive during chronic treatment and that supersensitivity remains up to 96 hours following withdrawal.
Majchrzak
M J
MJ
Department of Psychiatry, University of Michigan, Ann Arbor.
Dilsaver
S C
SC
D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D004347:Drug Interactions; D000431:Ethanol / Q000494:pharmacology*; D008297:Male; D010095:Oxotremorine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011976:Receptors, Muscarinic / Q000502:physiology; D012016:Reference Values; D013997:Time Factors
D011976:Receptors, Muscarinic; D000431:Ethanol; D010095:Oxotremorine