Effect of breastfeeding piperine on the learning of offspring mice: interaction with caffeine and diazepam.

Piperine, the main alkaloid of black pepper (Piper nigrum), has been suggested to display several pharmacological properties, including pain relief, anticonvulsant, antidepressant-like, antianxiety, sedative, and anti-inflammatory effects. This study was designed to investigate the effect of piperine on learning in mice and the interaction of the effect with caffeine and diazepam. Piperine (100 mg/kg intraperitoneally) was injected into the mouse mothers or nursing dams during breastfeeding for 25 days at five-day intervals.