Heteropterys aphrodisiaca (extract BST0298): a Brazilian plant that improves memory in aged rats.

Literature report is lacking on pharmacological studies of the plant Heteropterys aphrodisiaca, endemic to the scrublands of Brazil. The present study was carried out to investigate the effects of oral dosing with extract BST0298 from this plant, on learning and on memory, in young (3-6-month-old) and aged (20-28-month-old) rats. The aged animals presented significant memory deficits in both the passive avoidance and T-maze left/right discrimination tests. Treatment for 7 days (50 mg/kg) or 26 days (100 mg/kg) with extract BST0298 restored the memory deficits in the passive avoidance test. However, no improvement in memory was observed after acute administration of extract BST0298 (100 mg/kg) in aged rats. An improvement in learning was also observed in the left/right discrimination test in aged rats treated for 109 days with BST0298 at a dose of 50 mg/kg. These results suggest that treatment for 7 days or more with H. aphrodisiaca improves learning and memory deficits in aged rats.