Effects of Jatropha gossypiifolia L. on the blood pressure and vascular reactivity of rats

This work investigated the effects of the ethanolic extract (EEJg) of aerial parts of Jatropha gossypiifolia L. and its aqueous (AFJg) and chloroformic (CFJg) fractions on the blood pressure and vascular reactivity (VR) in normotensive Wistar rats (NWR) and spontaneously hypertensive rats (SHR). In anaesthetized NWR, the EEJg and its fractions reduced mean blood pressure (MAP). The oral administration of EEJg (100 mg/kg/bw), for 8 weeks, did not alter MAP and heart rate in the nonanesthetized SHR. VR was determined in mesenteric artery rings, with the EEJg and fractions inhibiting the contractile responses to noradrenaline (NA, 10 -9 to 10 -4 M) in NWR, but not in SHR. In addition, the CFJg inhibited the contractile response to calcium (CaCl2, 10 -6 to 10 -2 M). These results suggest that J. gossypiifolia L. has no effect on the hypertensive factors in SHR, which is a model of polygenic hypertension, but indicate the presence of substances with hypotensive activity, which act directly on the adrenoceptor and/or decrease calcium mobilization in NWR.