Pretreatment of young mice with nerve growth factor enhances scopolamine-induced hyperactivity.

Twenty-one-day-old mice show a characteristic enhancement of locomotor activity upon injection of the cholinergic (muscarinic) blocking drug scopolamine. Intracerebral (third ventricle) injection of nerve growth factor (NGF) 24 h prior to scopolamine injection significantly enhances the drug-induced hyperactivity without modifying baseline activity. Such potentiation of the scopolamine effect was not obtained in 10-week-old mice treated and tested similarly.