Sea snake Hydrophis cyanocinctus venom. II. Histopathological changes, induced by a myotoxic phospholipase A(2) (PLA(2)-H1)

A toxic phospholipase A(2) (PLA(2)-H1), isolated from the venom of the sea snake Hydrophis cyanocinctus, was tested for its ability to induce myonecro sis and histopathological changes in albino rats and mice. Induction of myo necrosis was demonstrated by their ability to release creatine kinase (CK) from damaged muscle fibers and direct histopathological examination of the injected muscles (i.m.), PLA(2)-H1 exhibits intense myonecrosis characteriz ed by the changes including, necrosis and edematous appearance with cellula r infiltrate, vacuolation and degenerated muscle cells with delta lesions a nd heavy edema in between the cells. No myoglobinuria was noted in any grou p of animals. The purified PLA(2)-H1 was also administered intraperitoneall y into the experimental animals and tissue samples were taken at several ti me intervals. Light microscopic examination of the kidney sections revealed severe damage, evident by focal: tubular necrosis complete disquamation of epithelial lining and epithelial degeneration of tubules in all test anima ls. tight micrographs of liver sections after 24 h of injection shows fatty infiltration in parenchyma and squashed hepatocytes, while after 48 h, fat ty vacuolation of parenchyma in a generalized pattern was observed. Further more, sections of the lungs of the same group of animals (48 h) show dilate d bronchia and marked infiltration of inflammatory cells within alveoli. Ou r results suggest that the purified PLA(2)-H1 induced moderate myotoxicity in muscles and mild histopathological changes in ether vital organs without myoglobinuria. (C) 1999 Elsevier Science Ltd, All rights reserved.