Effect of vascular endothelial growth factor on pre-eclampsia in pregnant rats

Abstract

To investigate relationship between the vascular endothelial growth factor (VEGF) and the pathogenesis of pre-eclampsia in pregnant rats. Pregnant rats were divided into two groups randomly. Saline solution or L-nitro arginine methyl ester (L-NAME) 125 mg/d was given subcutaneously from day 7 of gestation till establishing pre-eclampsia. Systolic blood pressure, urine protein, platelet count, and weight of pups and placenta were determined. The levels of VEGF in pregnant rats venous serum, placenta and decidual tissue from normal pregnancy and pre-eclampsia rats were detected by ELISA and immunohistochemistry, respectively. Pregnant rats which were given L-NAME produced physical signs similar to those of pre-eclampsia, such as increase in systolic blood pressure [(145.3 +/-4.6)mmHg] and urine protein [(814.3 +/-57.5)mg/L], and decrease in platelet count [(467.1 +/-76.3) x 10(9)/L] and weight of pups and placenta. Compared with controls, the intensity of VEGF immunostaining in trophoblast or decidual cells were significantly reduced. The serum levels of VEGF were significantly lower in pre-eclampsia group than in normal pregnancy. Decreased serum levels of VEGF and reduced expression of VEGF in placental tissues might in part explain the pathogenesis of pre-eclampsia in pregnant rats.