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.
Gould
T J
TJ
Temple University, Department of Psychology, Weiss Hall, rm. 865, 1701 N. 13 Street, Philadelphia, PA 19122, USA.
Collins
A C
AC
Wehner
J M
JM
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