Antihemorrhagic factors from the blood serum of the western diamondback rattlesnake Crotalus atrox.

Several antihemorrhagic factors isolated from C. atrox serum are glycoproteins with mol. wt ranging from 65,000 to 80,000. The antihemorrhagic activity of these factors was stable at a pH range of 1.3-11.5 and at temperatures up to 85 degrees C, for 30 min. The isolated antihemorrhagins also neutralized the proteolytic activity of C. atrox venom, as tested with azocollagen and gelatin, and formed a complex with hemorrhagic toxin e isolated from the same venom. The neutralization capacity of the isolated antihemorrhagins was six times as high as the commercial polyvalent antivenom produced for clinical use.