- INTRODUCTION: Psychostimulants such as amphetamine (AMPH) induce manic-like symptoms in humans and studies have suggested that bipolar disorder (BD) may be associated to dopamine dysfunction. Glial fibrillary acidic protein (GFAP) up-regulation is considered a marker of astrogliosis, and it has been associated to behavioral sensitization. PURPOSE: We aimed to investigate the behavioral effects of acute and chronic AMPH on rat locomotion and assess GFAP levels in rat cortex and hippocampus. METHODS: Rats were administered either acute (single dose) or chronic (seven days) d-amphetamine IP injection. Locomotion was assessed with an open-field test and GFAP immunoquantity was measured using ELISA. RESULTS: Chronic, but not acute, administration of AMPH increased GFAP levels in rat hippocampus. No differences were observed in rat cortex. CONCLUSIONS: Repeated exposure to AMPH leads to an astroglial response in the hippocampus of rats.