Crotamine-like from Southern Pacific rattlesnake (Crotalus oreganus helleri) Venom acts on human leukemia (K-562) cell lines and produces ultrastructural changes on mice adrenal gland.

Crotamine is a cationic, non-enzymatic, protein integrating a minor family of myotoxins, composed of 42 amino acid residues, described in Viperidae and Crotalidae snake's families that has been used in neuroscience research, drug progressing and molecular diversity reports. Crotamine-like protein (CLP) from C.o.helleri venom was isolated in fraction 5 from 7 peaks obtained by sulfopropyl waters protein pak cationic exchange column. In tricine-SDS-PAGE under non-reduced conditions this CLP showed a single band of ~8 kDa molecular weight. CLP induced toxicity of K-562 cells with a CC50 of 11.09 µM. In mice adrenal gland after 24 h of CLP injection, cortical cells exhibited swollen mitochondria with scarce tubular cristae, some elements of smooth and rough endoplasmic reticula, widened nuclear envelope, slightly osmiophilic lipid droplets, and autophagic vacuoles. In some areas cortical cells plasma membrane and endothelial walls disappeared, which indicated a necrosis process. In other areas, endothelial cell cytoplasm did not present the normal caveolae and pinocytotic vesicles. To our knowledge, this is the first report on mice adrenal gland damages, caused by the injection of CLP from rattlesnakes. Our results propose that adrenal cortex lesions may be significant in the envenoming etiopathogenesis by CLP.