Isolation and Biological Activity of Viriditoxin and a Viriditoxin Variant from Crotalus Viridis Viridis Venoms

Abstract Viriditoxin (VT) and viriditoxin variant (VTwo) are both slightly acidic high molecular weight hemorrhagic and myotoxic components which were isolated from prairie rattlesnake (Crotalus viridis viridis) commercial and western Oklahoma venoms, respectively. These toxins were isolated in three steps: gel filtration using Sephadex G150-120, followed by ion-exchange using DEAE Bio-gel A, then by gel filtration or ion-exchange to homogeneity as determined by disc electrophoresis. VT and VTwo are similar in several respects including biological activities, but different in other respects. The differences are most likely due to intraspecies variation. Light microscopic examination of thick (lm m) sections of muscle taken from mice after intramuscular injection with VTwo after 15 min, 1 h, 3 h, 6 h, 12 h, 24 h, 48 h, 72 h, and 96 h revealed hemorrhage by 15 min while myonecrosis was not observed until 12 h. Creatine phosphokinase levels were highest in pLasma collected 12 and 24 h after injection. These preliminary observations indicate that myonecrosis caused by VTwo (and VT) may be a secondary consequence of ischemia caused by their hemorrhagic activity.