. Increase of antioxidant enzymes and matriz metalloproteinases in stressed rat placentas.

ROMANINI MC; PAZ D.A.; PUSTOVRH C.; ROLANDO AN; MUGNAINI MT; SOÑEZ CA; BOZZO AA; PASTORINO IC; GAUNA HF

Los Cocos. Córdoba

Congreso; III Latin American Symposium on maternal-fetal interaction and placenta: basic & clinical research.; 2007

Our objective was to determine whether chronic immobilization stress (IMO) applied to pregnant rats alters the generation of reactive oxygen species (ROS), the activity of MMP2 and MMP9 metalloproteinase and the expression of the vascular endothelial growth factor (VEGF). Wistar pregnant rats were divided in control (C) and a stressed (S) groups, and sacrificed at 12, 17 and 21 days. The levels of nitric oxide (NO), lipoperoxide and activity of nitric oxide synthases (NOS), superoxide dismutase (SOD), catalase, MMP2, MMP9 were determined in placental tissue and nitrotyrosine and VEGF were examined by immunhistochemistry. The values of SOD and catalase were found increased in groups 17 and 21 S. MMP2 activity was rised in 12 S and MMP9 in 17 and 21 S groups. VEGF displayed an intense expression in 12, 17 and 21 S groups, as nitrotyrosine in 17 S. The increase of antioxidant enzymes towards last pregnancy would indicate an increase ROS however, we did not found significant differences in NO, NOS and lipoperoxides values between C and S groups. MMP2 and MMP9 activities were elevated different stages of pregnancy in stressed rat placenta, which would indicate a greater tissue remodelling of the different placental zones. On the other hand, the greater VEGF expression could stimulate the angiogenic process in the placenta of stressed rats.