ABSTRACT
A haemorrhagic toxin (VRR-12) from Vipera russelli russelli (Russell's viper) venom has been purified by ion-exchange chromatography on CM-Sephadex C-50 followed by size-exclusion HPLC to electrophoretically homogeneous state. It is a 12 kDa single polypeptide having 1 mole of Zn+2 ion. This toxin induces intense intestinal haemorrhage and to a lesser extent skeletal muscle haemorrhage in mice. It does not show detectable proteolytic and esterolytic activity with selected substrates under specified conditions, haemolytic and phospholipase activity. When VRR-12, preincubated with bivalent antiserum against Saw-scaled and Russell's viper venom or EDTA was injected, haemorrhagic activity was not reduced, on the other hand preincubation with phenylmethyl sulphonyl fluoride reduced the activity markedly. Biodistribution studies with 125I VRR-12 show that haemorrhagic manifestation by this toxin is not a direct function of the fraction of the totally administered toxin distributed to that tissue.