12 Expression of corticotropin-releasing hormone in the placentas of pregnant women with hypertensive disorders

Abstract

Introduction the human placenta is an extrahypothalamic site for the synthesis and secretion of corticotropin-releasing hormone (CRH). Receptors CRH-R1 and CRH-R2 are expressed in the syncytiotrophoblast, in the cytotrophoblast, in the decidua, and in the vascular endothelium. Studies have showed an increased expression of CRH in cases with preeclampsia. Objective this study aimed to evaluate the expression of CRH in the chorionic villi and in the decidua of human placentas of women with different types of hypertensive disorders of pregnancy (HDP). Methods 116 placental biopsies collected from 2013 to 2014 were analyzed, and they were grouped as follows: (a) control group (C): 12 cases; (b) gestational hypertension (GH): 23 cases; (c) preeclampsia/eclampsia (PE): 30 cases; (d) chronic hypertension (CH) 25 cases and (e) preeclampsia superimposed on chronic hypertension (PSCH): 26 cases. Of these cases, 54 biopsy samples were from preterm deliveries ( ⩾ 37 weeks). The expression of CRH in the chorionic villi and in the decidua was assessed by immunohistochemistry; the immunostained areas were quantified using Leica Qwin Plus® image analysis software and expressed as percentage of positive area per field. ANOVA (F) followed by Tukey’s test was used for statistical analysis; p 0.05. Results 33.33% (18) of preterm pregnancies were diagnosed with PE, 20.37% (11) were diagnosed with GH, 20.37% (11) had CH, and 25.93% (14) had PSCH; whereas 19.35% (12) of term pregnancies had PE, 19.35% (12) were diagnosed with GH, 22.58% (14) had CH, 19.35% (12) PSCH, and 19.35% (12) were control cases. In term pregnancies, cases with PE, GH, CH and PSCH showed an increased expression of CRH in the chorionic villi and in the decidua than group C (p 0.0001). In the preterm group, the expression was higher in cases associated with PE and PSCH in both regions. Conclusions altered expression of CRH is observed in HDP, and it occurred in all types of term HDP in both regions analyzed. In preterm pregnancies, expression was more prominently increased in the decidua of the PE and PSCH cases. Therefore, CRH expression behaved similarly in term pregnancy cases with HDP, but the expression varied in the preterm cases associated with PE, thus demonstrating that the levels of placental oxidative stress were higher in these cases. Download : Download high-res image (372KB) Download : Download full-size image