Intravascular hemolysis in dogs induced by Echis coloratus venom

Separation and purification of Echis coloratus venom and some biological and biochemical effects of the proteins

Crude venom of Echis coloratus was separated into seven protein fractions using 7% preparative native polyacrylamide gel electrophoresis. The effect of crude venom and seven venom protein fractions (F1-F7) from Echis coloratus on key metabolic activities of fibroblast cultures was investigated. Confluent cultures were incubated with the venom proteins for 3 h at 37 degrees C. The specific activity of phosphofructokinase, was significantly lowered upon incubation with the crude venom and with fractions 2, 3, 4 and 6. Citrate synthase activity was significantly lowered by the crude venom and by fractions 2 and 3. Glycogen phosphorylase activity was significantly increased by the crude venom and by fractions 2, 3, 4 and 6 leading to a significant concurrent drop in glycogen content. Creatine kinase activity was significantly increased by the crude venom and by fractions 3, 4, 5 and 6. Cellular ATP levels rose significantly upon incubation with the crude venom and with fractions 3, 4, 5 and 6. Incubation of cell sonicates with all the venom proteins did not significantly alter the activity or content of any of the studied parameters.

Studies on hemoglobinuria produced by venom from the Australian snake Tropidechis carinatus (rough-scaled snake)

Hemoglobinuria occurs in rats, but not in mice, after i.p. application of Tropidechis carinatus venom. By gel filtration on Sephadex G-75 and G-50 and chromatography on SP-Sephadex C-25 and DEAE-cellulose, a coagulant factor and a phospholipase A were isolated from the venom which in combination only, produced hemoglobinuria.

Comparison of phospholipase activity with direct and indirect lytic effects of animal venoms upon human red cells

1. The venoms of 22 species of arthropods, saurians, elapids and crotalids were studied concerning the phospholipase activity and the presence of a direct and an indirect lytic effect upon human red cells. 2. The venoms from the spiders Latrodectus and "tarantula", and the venoms from the scorpions of the genus Centruroides are not haemolytic and do not have phospholipase activity. 3. Only the venoms of Apis mellifera and Naja naja siamensis have shown direct lytic effect. 4. All other venoms studied have an indirect haemolytic effect associated to a phospholipase activity, but there is indication that other agents might be implicated in the haemolytic processes.

Morphological study of lesions induced by snake venoms (Naja naja and Agkistrodon piscivorus) in the lung and cremaster vessels of rats

The morphological effects of two snake venoms, N. naja and A. piscivorus, and of the Direct Lytic Factor and Phospholipase-A, compounds purified from N. naja crude venom, were investigated on lung and cremaster vessels of rats. The microcirculation of the rat reacts to these two venoms differently: N. naja produces congestion, haemolysis and increased vascular permeability, whereas A. piscivorus causes these alterations, plus haemorrhage and thrombosis. Direct Lytic Factor elicits reponses similar to the N. naja venom but Phopholipase-A has no effect on the vessels. Phospholipase-A does not seem to potentiate the effects of Direct Lytic Factor on the cremaster vessels. The colloidal carbon technique showed that intrathroacic administration of N. naja venom results in a generalised permeability increase of pleural and subpleural capillaries and A. piscivorus injections provoke only carbon retention in capillaries at sites of localised haemorrhage. In cremasters treated with N. naja venom the carbon blackened the venules predominantly but in cremasters in which A. piscivorus venom was administered the carbon particles labelled both venules and capillaries. There was evidence that the main vascular action of the venoms is local and not systemic, that the permeability factors involved in these lesions are different and that the cremaster vessels are much more sensitive to these snake venoms than the pulmonary vessels. Electron-microscopic studies showed mesothelial and epithelial lesions in lungs and an early inflammatory reaction in the cremaster vessels with both venoms. Erythrocyte fragmentation was a constant feature in all vessels. Endothelial degeneration and capillary disintegration in lung and cremaster vessels were observed in animals treated with A. piscivorus venom.