LOW ENERGY LASER EFFECTS IN MYONECROSIS CAUSED BY Bothrops jararacussu  CRUDE VENOM

SILVA, R.D.A.(1), LEITE, G.B.(1), RODRIGUES-SIMIONI, L.R.(1), CRUZ-HÖFLING, M.A.(2)

(1)Department of Pharmacology, (2)Department of Histology and Embryology, UNICAMP, Campinas, SP, Brasil.

Objective: The severity of the local effects caused by B. jararacussu (Bjssu) snake accidents prompted us to investigate these rapidly developing biological phenomena and also to follow the time course of the injurious process as well as to search for new approach to neutralize the severe muscle damage that occurs in the snakebites victims. The present innovating work investigates the possible benefits of irradiating the region affected by B. jararacussu venom with low energy He-Ne laser (KLD – Biosistemas Equip. Eletron. Ltda, Amparo, SP, l= 632.8 nm, 5 mW). Histopathological and myographical analysis were done to assess the laser treatment. Methodology:The tibialis anterior muscle of adult anesthetized Wistar rats (250–350 g) were prepared for myographic records. After stabilization of the in vivo preparation the muscle was injected in the medium third either with (Bjssu) (60 g/0.02 ml) or sterile saline (controls). Irradiated and unirradiated groups were investigated (n=3/group). Three laser doses were administered (30 mJ/cm² -9 sec, 90 mJ/cm² - 27 sec and 30 mJ/cm² - 9 sec at each 20 min) after 60 min post-venom or post-saline injection and the effect was observed during 60-120 min. After myographic recording the muscles were rinsed and fixed with Bouin’s fixative for histopatological studies. Results: The results revealed that the dose of 30 mJ/cm² produced a significant decrease of the neuromuscular blockade compared to unirradiated groups. In addition, smaller percentage of myonecrosis per muscle sections were detected with this same dose. Conclusion: We concluded that the irradiation with low energy laser can prevent the progress of the myonecrotic process caused by the inoculation of the B. jararacussu venom in in vivo preparation.

Support: CAPES

CORRESPONDENCE TO:

Maria Alice da Cruz-HÖfling, Rua Fernão de Magalhães 1017, Campinas, SP, CEP: 13087-130, Brasil, Email: hofling@unicamp.br