Capillary permeability responses to snake venoms

Abstract
Russell’s viper venom is many times more toxic to mice on intravenous administration than is saw-scaled viper venom, and yet on local intradermal injection the two venoms have equal capillary permeability effects in mice, rats, guinea-pigs and rabbits. Their effects are completely prevented by drugs possessing both antihistamine and anti-5-ht properties. It is concluded that the increased capillary permeability induced by the venoms is largely mediated through the release of histamine and 5-ht.