Nicotine enhances latent inhibition and ameliorates ethanol-induced deficits in latent inhibition.
Alcohol and nicotine are drugs of abuse that are used frequently together. One possible explanation for this co-administration is that nicotine prevents or lessens alcohol-associated impairments. The present study examined the dose-dependent effects of acute administration of nicotine, alcohol, or alcohol plus nicotine on latent inhibition as measured by lick suppression in C57BL/6 mice. Alterations in a lick suppression ratio were measured by assessing the effects of 10 pre-exposures to an auditory conditioned stimulus (CS) on formation of subsequent CS-shock unconditioned stimulus (US) associations. Mice pre-exposed to the CS were expected to develop a weaker CS-US association. Nicotine administered prior to pre-exposure to the CS produced increased suppression ratios, ethanol given prior to pre-exposure to the CS decreased suppression ratios, and nicotine reversed the effects of ethanol when the two drugs were co-administered. These opposing actions of nicotine and ethanol may have relevance to the high incidence of smoking and drinking in humans.
Temple University, Department of Psychology, Weiss Hall, rm. 865, 1701 N. 13 Street, Philadelphia, PA 19122, USA.
T J
TJ
Gould
A C
AC
Collins
J M
JM
Wehner
D000818:Animals; D001070:Appetitive Behavior / Q000187:drug effects; D001522:Behavior, Animal / Q000187:drug effects; D003214:Conditioning, Classical / Q000187:drug effects; D000431:Ethanol / Q000009:adverse effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009433:Neural Inhibition / Q000187:drug effects*; D009538:Nicotine / Q000494:pharmacology*; D011930:Reaction Time / Q000502:physiology
D000431:Ethanol; D009538:Nicotine