A study on the experimental envenomation in mice with the venom of Tityus trivitattus Kraepelin 1898 (Scorpiones, Buthidae) captured in Argentina.

Although Tityus trivitattus is the only scorpion species reported to cause severe human envenomation in Argentina, no previous studies on its venom have been done. Telson homogenates from T. trivitattus specimens collected in Santiago del Estero, Cordoba, and Buenos Aires were employed to study their protein composition and toxicity to mice. Regardless of the site of collection, electrophoretic analysis showed bands at 205, 150, 100, 40, 32, and 13 kDa or smaller. FPLC gel filtration showed three major peaks and 6-8 minor peaks with similar elution volumes. One of the minor peaks from FPLC containing a component of approximately 8 kDa was lethal to mice. Mice injected intravenously with different doses of homogenates presented severe autonomic signs like tachypnea, tachycardia, sialorrhea, lacrimation, profuse sweating, diarrhea, dyspnea, and death. Pathology studies of lungs showed severe congestion of alveolar capillaries, pulmonary edema, and hemorrhagic areas. The kidneys showed glomerular as well as tubular lesions and exocrine glands showed areas of necrosis. The calculated LD50 was 0.38 +/- 0.08 telsons per 20 g mouse, which suggests a lethal potency similar to that of T. serrulatus venom. The lethal potency of 5.0 LD50 of T. trivitattus telson homogenate was neutralized by both an anti-T. trivitattus and a heterologous anti Tityus with ED50 values of 41 +/- 19 and 170 +/- 42 microl, respectively.