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.
Highfield
D A
DA
Department of Psychology and Institute for Neuroscience, University of Texas at Austin, 78712, USA.
Lilliquist
M W
MW
Amsel
A
A
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