Persistent downregulation of hippocampal CREB mRNA parallels a Y-maze deficit in adolescent rats following semi-chronic amphetamine administration

Abstract

BACKGROUND AND PURPOSE: We investigated possible differences in the impact of chronic amphetamine administration during adolescence and adulthood on aspects of behaviour and brain chemistry. EXPERIMENTAL APPROACH: Adult (n=32) and adolescent (n=32) male Sprague-Dawley rats were given either D-amphetamine sulphate (10 mg kg(-1) daily, i.p.) or saline (1 mL kg(-1), i.p.) for 10 days. Rats were subsequently tested for anxiety-like behaviour, learning and memory, and sensorimotor gating. Nine weeks later, rats received saline (1 mL kg(-1)) or acute amphetamine challenge (1.5 mg kg(-1)) and the expression levels of mRNA for tyrosine kinase B (TrkB) or cAMP response element-binding protein (CREB) ..