Inhibition of adrenaline-induced aggregation of human platelets by Pakistani medicinal plants

Pak J Pharm Sci. 1991 Jul;4(2):145-52.


The effects of extracts of Pakistani plants claiming medicinal value were observed on adrenaline-induced aggregation of human platelets according to the method of Born (1962). The extracts manifested significant inhibitory activity in doses of 0.625 mgm(-1) to 2.5 mgml(-1) in this in vitro model. The potency of the plant extracts in inhibiting platelet aggregation induced by adrenaline is in the following order: Sida pakistanica, IC50 = 0.90 mgml(-1) > Tribulus terrestris, IC50 = 0.97 mgml(-1) > Solanum surattense, IC50 = 1.34 mgml(-1) Tephrosia subtriflora, IC50 = 1.40 mgml(-1) > Glycyrrhiza glabra (butanolic extract), IC50 = 1.66 mgml(-1) > Urtica dioica IC50 = 2.17 mgml(-1). Further studies are proposed to find out whether the inhibition of adrenaline-induced platelet aggregation is mediated through alpha-adrenoceptor blockade or suppressed synthesis of prostaglandin endoperoxides.