5-HT1A receptor blockade and the motivational profile of ethanol.
Although several serotonin (5-HT) receptor subtypes influence ethanol consumption, the motivational mechanisms underlying these changes remain unclear. The present experiments characterized the rewarding, aversive and stimulant effects of ethanol in combination with a specific 5-HT1A receptor antagonist (pindobind-5HT1A). In a place conditioning study, adult male Swiss-Webster mice received 6 parings of a distinctive tactile stimulus with either 2 g/kg ethanol, 2.5 mg/kg pindobind-5HT1A, or both drugs in combination. Ethanol-conditioned preference for the tactile cue was enhanced in mice also receiving pindobind-5HT1A, which did not produce cue preference in the absence of ethanol. In a taste conditioning study, Swiss-Webster mice received 4 trials consisting of access to a distinctive NaCl flavor followed by either 4 g/kg ethanol, 2.5 mg/kg pindobind-5HT1A, or both drugs. As expected, ethanol produced avoidance of the flavor. Pindobind-5HT1A did not reduce or enhance ethanol-conditioned flavor aversion. In a study characterizing locomotor activity, 2 g/kg ethanol produced stimulation, which was enhanced after 10 daily treatments. Locomotor sensitization was not altered by co-treatment with pindobind-5HT1A. Overall, the present results show specific effects of 5-HT1A blockade on ethanol reward.
Risinger
Fred O
FO
Department of Behavioral Neuroscience, L470, Oregon Health and Science University, Portland, Oregon 97201-3098, USA. risinger@ohsu.edu
Boyce
Janel M
JM
D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects; D003463:Cues; D000081005:Cyclohexane Monoterpenes; D000431:Ethanol / Q000494:pharmacology*; D006185:Habituation, Psychophysiologic / Q000187:drug effects; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects; D010869:Pindolol / Q000031:analogs & derivatives* / Q000494:pharmacology; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology*; D044263:Receptors, Serotonin, 5-HT1; D012702:Serotonin Antagonists / Q000494:pharmacology*; D013649:Taste / Q000187:drug effects / Q000502:physiology; D014110:Touch
D000081005:Cyclohexane Monoterpenes; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D012702:Serotonin Antagonists; C084712:pindobind; D000431:Ethanol; D010869:Pindolol