The decreased expression of Stat3 and p-Stat3 in preeclampsia-like rat placenta.

This study aims to investigate the expression of Stat3 and p-Stat3 in the placenta of a preeclampsia-like rat model induced by Nωnitro-L-arginine methyl ester (L-NAME). Two-to three-month-old (20 males, 40 females) Sprague-Dawley rats were used in this study. After conception was confirmed by vaginal smears, on the thirteenth day of pregnancy, the animals were allocated into two groups: control (0.9% NaCl administered) group and L-NAME (75 mg/kg) group. After the treatment of L-NAME, there was a significant increase in systolic blood pressure (SBP) levels in the L-NAME group (148.5 ± 5.71 mmHg) on day 21 compared to the SBPs in the control group (117.5 ± 4.57 mmHg) (P < 0.001). There was also an increase in total proteinuria on day 21 in the L-NAME group (766.57 ± 17.7 mg/L), when compared to the control group (459.89 ± 20.1 mg/L) (P < 0.001). Moreover, we also found a decrease in fetal numbers and fetal weight in the PE group in comparison to the control group. After the rats were sacrificed, the placentas were obtained from both groups. We found that the L-NAME group exhibited fewer placentas compared with the control group. Furthermore, the immunohistochemistry (IHC) and Western blot results showed that decreased expression of Stat3 and p-Stat3 were detected in the placenta of the preeclampsia-like rat model compared to Stat3 and p-Stat3 in the control group. We found the expression and activation of Stat3 and p-Stat3 were decreased in the placenta of the L-NAME-induced preeclampsia rat model.