Reversal of a postnatal alcohol-induced deficit in learned persistence in the rat by d-amphetamine.
Periodic (high peak) exposure to alcohol during early infancy in the rat has been shown to disrupt the partial reinforcement extinction effect (PREE), a measure of persistence learning, when rats were tested at weaning age. The current study examined the effects of d-amphetamine (0.3 mg/kg, i.p.) on the PREE after early postnatal exposure to alcohol (4.5 mg/kg) delivered in a milk-based diet or an isocaloric control diet via oral intubation once a day on postnatal days 4 to 9. On postnatal days 20 and 21, rats were trained on either a continuously reinforced or partially reinforced schedule of food reward, followed by extinction. Rats were randomly assigned to eight conditions, depending on diet, drug, and reward schedule. The results were (1) a replication of the finding that periodic (high peak) exposure to alcohol diminishes the PREE, and (2) that amphetamine restores the PREE to normal levels in alcohol-treated animals, and may reduce the PREE in control subjects. The possible role of noradrenergic and dopaminergic systems in situations of extinction and nonreward are discussed.
Department of Psychology and Institute for Neuroscience, University of Texas at Austin, 78712, USA.
D A
DA
Highfield
M W
MW
Lilliquist
A
A
Amsel
D000818:Animals; D000831:Animals, Newborn; D001289:Attention Deficit Disorder with Hyperactivity / Q000209:etiology / Q000503:physiopathology; D002492:Central Nervous System Depressants / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003913:Dextroamphetamine / Q000494:pharmacology*; D000431:Ethanol / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D007858:Learning / Q000187:drug effects*; D009043:Motor Activity / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012054:Reinforcement, Psychology
D002492:Central Nervous System Depressants; D000697:Central Nervous System Stimulants; D000431:Ethanol; D003913:Dextroamphetamine