In Vitro Effects of Ethanolic Extracts of Pterocarpus santalinoides Leaves on the Isolated Uterine Tissues of Non -Gravid Albino Wistar Rats:- Iheonunekwu, Goodness Chigozirim

ABSTRACT

The aim of this study was to determine the effect of the Ethanolic Extracts of Pterocarpus Santalinoides leaves (EEPSL) on isolated uterine smooth muscle of non-gravid rats and to deduce its possible mechanism(s) of action. The extract of Pterocarpus santalinoides leaves mimicked Oxytocin in producing a concentration dependent uterine contraction and the maximum response which was significant (P < 0.05) was observed at the least concentration (14.25mm, 0.33mg/ml). Increasing the concentration of the extract (1.33mg/ml) did not increase the response of the extract on the isolated uterine smooth muscle but rather, recorded the least response effect (with amplitude of 8.50mm). Similar to Oxytocin, the percentage activity was highest and significant (P < 0.05) at the least concentration (271.25%, 0.33mg/ml) though not significant (P > 0.05) with the percentage activity recorded at the double concentration 0.66mg/ml and 1.33mg/ml (243.75% and 197.90%) respectively. Further investigation to deduce the possible mechanism of action of the extract showed that independent introduction of a calcium channel blocker Verapamil (0.0067mg/ml), and a selective B adrenergic blocker Salbutamol (0.0067mg/ml) respectively, completely abolished the EEPSL (0.33mg/ml) induced uterine force thereby showing involvement of mobilization of extracellular calcium and stimulation of-adrenegic receptors in the mechanism of action. The findings of this study suggests that EEPSL may possess potent uterotonic principle(s) hence the traditional use of the plant for flushing unwanted uterine contents post-partum. Further studies are hereby recommended to isolate and purify and characterize the active ingredient responsible for this contractile effect.