4-OH amphetamine enhances retention of an active avoidance response in rats and decreases regional brain concentrations of norepinephrine and dopamine.
An .82 mg/kg dose of dl-4-OH amphetamine administered ip immediately following training in a one-way active avoidance task enhanced retention performance measured 24 hr later. In contrast, 4-OH amphetamine in a dose range of .41--1.65 mg/kg ip did not affect retention of a swim escape task. The behaviorally active dose of .82 mg/kg 4-OH amphetamine decreased dopamine concentrations in the amygdala and hippocampus. A dose of 8.2 mg/kg 4-OH amphetamine administered ip to naive untrained rats decreased concentrations of norepinephrine measured in the amygdala, cortex, hippocampus, hypothalamus, and midbrain; decreased concentrations of dopamine in the amygdala, cortex, hippocampus, and striatum; and significantly reduced concentrations of norepinephrine and epinephrine in the adrenal medulla. In addition, because the integrity of the adrenal medulla is necessary for the enhancing action of 4-OH amphetamine and because 4-OH amphetamine reduces concentrations of catecholamines in the brain and adrenal medulla, it is possible that 4-OH amphetamine affects retention performance by a dual action on the brain and the adrenal medulla.
D000313:Adrenal Medulla / Q000187:drug effects; D000662:Amphetamines / Q000494:pharmacology*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001921:Brain / Q000187:drug effects*; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000378:metabolism; D004924:Escape Reaction / Q000187:drug effects; D008297:Male; D008568:Memory / Q000187:drug effects*; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012153:Retention, Psychology / Q000187:drug effects*; D010136:p-Hydroxyamphetamine / Q000494:pharmacology*
D000662:Amphetamines; D010136:p-Hydroxyamphetamine; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine