PURIFICATION AND PARTIAL CHARACTERIZATION OF A HAEMORRHAGIN (VRH-1) FROM VIPERA-RUSSELLI RUSSELLI VENOM

A haemorrhagic toxin (VRH-1) has been purified to homogeneity from Vip era russelli russelli venom by subjecting it to chromatography twice s uccessively on CM-Sephadex C-50. It is a protein of mel. wt 22,000 and contains one mole of Mg2+ Intradermal administration of this haemorrh agin in mice resulted in severe lung haemorrhage but produced little h aemorrhage in skin. This apparent organ preference led us to develop a new haemorrhage assay method utilizing dye diffusion from lung in vit ro. Proteolytic activity of VRH-1 was demonstrated using dimethylcasei n as substrate following quantitation by reaction with trinitrobenzoyl sulfonic acid. Both haemorrhagic and proteolytic activities of VRH-1 were inhibited by serine protease inhibitors like phenylmethyl sulfony l fluoride and chymostatin, but metal chelators had no effect. Lung ha emorrhage is unlikely to be a direct reflection of a high local concen tration of VRH-1. The administration of supernatant generated by incub ation of chopped liver from untreated mouse and VRH-1 (in subhaemorrha gic dose) results in severe lung haemorrhage. This raises the possibil ity that VRH-1 leads to the formation of intermediate(s) which causes the haemorrhage.