Nicotine enhances contextual fear conditioning and ameliorates ethanol-induced deficits in contextual fear conditioning.
Nicotine and ethanol are 2 commonly used and abused drugs that have divergent effects on learning. The present study examined the effects of acute nicotine (0.25 mg/kg), ethanol (1.0 g/kg), and ethanol-nicotine coadministration on fear conditioning in C57BL/6 mice. Mice were assessed for contextual and cued fear conditioning at 1 day and 1 week posttraining. Ethanol disrupted acquisition but not consolidation of contextual fear conditioning; nicotine enhanced contextual fear conditioning and ameliorated ethanol-associated deficits in contextual fear conditioning. Mecamylamine antagonized this effect. Fear conditioning was reassessed 1 week after initial testing with no drug administered. At the 1-week retest, mice previously treated with nicotine continued to show enhanced contextual fear, and mice previously treated with ethanol continued to show contextual fear deficits. Thus, nicotine both produces a long-lasting enhancement of contextual fear conditioning and protects against ethanol-associated deficits.
Gould
Thomas J
TJ
Department of Psychology, Neuroscience Program, Temple University, Philadelphia, Pennsylvania 19122, USA. tgould@temple.edu
Lommock
Joel A
JA
D000818:Animals; D002492:Central Nervous System Depressants / Q000494:pharmacology; D003214:Conditioning, Classical / Q000187:drug effects*; D004347:Drug Interactions; D000431:Ethanol / Q000494:pharmacology*; D005239:Fear / Q000187:drug effects*; D008297:Male; D008464:Mecamylamine / Q000494:pharmacology; D011939:Mental Recall / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology; D018733:Nicotinic Antagonists / Q000494:pharmacology
D002492:Central Nervous System Depressants; D018722:Nicotinic Agonists; D018733:Nicotinic Antagonists; D000431:Ethanol; D008464:Mecamylamine; D009538:Nicotine