Arterial antithrombotic effect of piyavit, the novel pharmacological preparation from the medicinal leech, and of its components, prostanoids and enzyme destabilase.

Piyavit, the novel pharmacological preparation from the medicinal leech (Hirudo medicinalis) contained the leech saliva, produces the potent arterial antithrombotic effect examined on experimental of Laser Induced Thrombus formation. Administrated orally into rats or injected subcutaneously as water extract, non-diluted or in 1600 times diluted, it inhibits statistically significant comparing with control platelet thrombus stimulated by laser beams. Its components, prostanoid fraction and purified enzyme destabilase, endo-epsilon-(gamma-Glu)-Lys-isopeptidase, also inhibit thrombus formation in statistically different manner, comparing with control. All the tested preparations inhibit platelet aggregation induced by ADP. The dependence of arterial antithrombotic effect on the leech prostanoid is discussed.