EFFECT OF Crotalus durissus terrificus (LAURENTI, 1768) AND Bothrops jararaca (WIED, 1824) VENOMS ON THE EVOLUTION OF EHRLICH ASCITES TUMOR

DISSERTATION: R. J. da Silva submitted this dissertation for the degree of Master of Science in Tropical Diseases at the Department of Tropical Diseases of the School of Medicine of Botucatu, São Paulo State University, São Paulo, Brazil in l995.

Advisor: Professor Benedito Barraviera

Co-Adivisor: Professor Denise Fecchio

ABSTRACT. The effect of Crotalus durissus terrificus (LAURENTI, 1768) and Bothrops jararaca (WIED, 1824) venoms on the evolution of Ehrlich ascites tumor was evaluated. Thus, mice of the Swiss strain, male, 30 days old were inoculated intraperitoneally with 1x 10 tumor cells. Then, for each venom, 7 groups of animals were formed: 3 control groups (physiological, venom and tumor) and 4 experimental groups that received different doses of venom. The experimental groups were given 5 intraperitoneal injections of venom on the 1st, 4th, 7th, 10th and 13th days after tumor implantation. On the 14th day, 5 animals from each one of the groups were sacrificed, and the following variables were evaluated: the total and differential counts of cells in the peritoneal cavity and the functional state of peritoneal macrophages by macrophage spreading. The other 5 remaining animals were kept in laboratory for 60 days for the observation of their survival percentage. The results obtained were statistically analyzed by the test of Kruskal-Wallis at a 5% significance level. It was observed that Crotalus durissus terrificus venom increases the survival time of mice, but does not increase their survival percentage. This venom also increases the percentage of macrophage spreading. Bothrops jararaca venom increases the animals' survival time and decreases their mortality. It also increases the number of mononuclear and polymorphonuclear cells, reduces the number of tumoral cells and increases the percentage of peritoneal macrophage spreading. It has been hypothesized that the interaction of the venoms (mainly Bothrops jararaca venom) and the immunological system may promote the release of the inflammatory response mediators, for instance, tumor necrosis factor-alpha (TNF- ), interleukin-1 (IL-1), IL-6 and IL-8. Such mediators might act on the activation of polymorphonuclear leukocytes, lymphokine-activated killer cells, cytotoxic T lymphocyte and natural killer cells. They might also act on the liver inducing the release of complement factor C3 and of C-reactive protein that lead to the opsonization of tumoral cells. These mechanisms might be responsible for the inhibition of tumor growth.

CORRESPONDENCE TO:

R. J. SILVA - Caixa Postal 577, CEP 18.618-000, Botucatu, São Paulo, Brasil.

Publication Dates

• Publication in this collection
  08 Jan 1999
• Date of issue
  1996