The cardiovascular activity of Aspidosperma macrocarpum leaves ethanol extract (AMLEE) was evaluated. In non-anesthetized normotensive rats showed hypotensive response without significant alterations in heart rate. AMLEE (1, 5, 10 and 20 mg/kg, iv) induced hypotension that was completely abolished after atropine (2 mg/kg, iv). The extract also produced in vitro relaxant effect on isolated mesenteric artery endotheliumintact rings. EEAM (200mg/kg, v.o.) promoted an antihypertensive activity. In conclusion, our results suggest that cardiovascular responses could be mediated by the endothelial muscarinic receptors.