Background: Mango belongs to the Anacardiaceae and the extracts from its stems, leaves, fruit and kernel are reported to affect smooth muscle contractility. We studied the role of   cholinergic muscarinic receptors for the effects of aqueous extract of mango kernel (Mangifera indica) on the basal activity of virgin rat uterine smooth muscle.

Materials and Methods: In this experimental study, mid-sections (n=24) of the uterine of healthy virgin rats were placed in an organ bath containing carbonated Tyrode’s solution under 1 g tension. The cumulative effects of the aqueous extracts of mango kernel (0.002, 0.02, 0.2, 2, 20, 200, and 2000 μg/mL) or extract vehicle (Tyrode’s solution) in the presence or absence of atropine were examined by isometric method using the strength, frequency and contractile activity of uterine smooth muscle.

Results: The cumulative concentrations (0.002-20 µg/ml) of mango kernel aqueous extract was significantly decreased the strength, frequency and contractile activity of uterine smooth muscle, but the contractile activity was returned to the basal level at the concentrations of 200 and 2000 µg/ml. Atropine (1 µM) could not significantly change the effects of cumulative use of extract on the strength and contractile activity of uterine smooth muscle, but it significantly enhanced the contractile frequency at low concentrations.

Conclusion: The effects of aqueous extract of mango kernel on the activity of the uterine smooth muscle might not be through cholinergic muscarinic receptors and atropine could enhance the effects of the extract on frequency through other receptors.