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J. Venom. Anim. Toxins incl. Trop. Dis. Vol.9, No.2, p.549, 2003. Poster - ISSN 1678-9199. |
EVALUATION OF CUTANEOUS LESIONS EXPERIMENTALLY INDUCTED BY Bothrops jararaca SNAKE VENOM
ARAUJO, L.F.(1), MACERA, J.M.P.(2), MELO, P.A.(3)
(1)Curso de Pós-Graduação em Dermatologia do Departamento de Clínica Médica, (2)Serviço de Anatomia Patológica, HUCFF; Departamento de Farmacologia Básica e Clínica, ICB, CCS, UFRJ, Rio de Janeiro, Brazil.
The development of malignant tumors has been subject of study in many different animal models. Previous report (Mello et al., Skeletal Radiol. 2000, 29(5):298-301) related a case about a man bitten accidentally by a snake of the genus Bothrops, which causes 90.4% of bites in Brazil. After complete recuperation from ulcerated lesion, it kept as assymptomatic scaling area. It turned into differentiated squamous cell carcinoma in 23 years. Due to lack of studies about inducted lesions by ophidian toxins non- related to acute phases, we tested protocol with histopathological study to characterise the inducted chronic morphological alterations. Swiss male mice and the B. jararaca venom were used in this study. The lesion was induced on the intermediate portion of the tail by venom intradermic injection (100 mg in 100 ml for each animal). The animals were sacrificed in several intervals (1, 2, 3, 7, 12, 14 and 23 days) under general anesthesia in order to remove the tail for histological processing. Macroscopic alterations showed evolution from acute reaction to healing. Some animals showed persistent ulceration, necrosis and keratosis. The microscopy revealed epidermal and dermal necrosis, acute inflammatory infiltrate, progressing to pseudo epitheliomatous hyperplasia, acanthosis, basal layer loss, disarrangement, pleomorphism and parakeratosis. Our experiments demonstrated the B. jararaca venom injection can produce difficult healing lesions in some animals whose histopathological studies revealed dysplastic alterations seen in pre-malignant lesions. The experiments also suggest this venom is instrument to study the epithelial regeneration.
Supported by CAPES, FAPERJ, FUJB and PRONEX
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