Cytotoxicity of snake venom Lys49 PLA2-like myotoxin on rat cardiomyocytes ex vivo does not involve a direct action on the contractile apparatus.

ABSTRACT: Viperid snake venoms contain a unique family of cytotoxic proteins, the Lys49 PLA₂ homologs, which are devoid of enzymatic activity but disrupt the integrity of cell membranes. They are known to induce skeletal muscle damage and are therefore named 'myotoxins'. Single intact and skinned (devoid of membranes and cytoplasm but with intact sarcomeric proteins) rat cardiomyocytes were used to analyze the cytotoxic action of a myotoxin, from the venom of Bothrops asper. The toxin induced rapid hypercontraction of intact cardiomyocytes, associated with an increase in the cytosolic concentration of calcium and with cell membrane disruption. Hypercontraction of intact cardiomyocytes was abrogated by the myosin inhibitor para-aminoblebbistatin (AmBleb). No toxin-induced changes of key pa

SUBMITTER: Lopez-Davila AJ 

PROVIDER: S-EPMC8484475 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature