Experimental hypertension and pregnancy in rats: repercussion regarding placental weight and placental index - Revista Brasileira de Ginecologia e Obstetrícia

Purpose: to study the repercussion regarding placental weight and placental index determined by induced experimental hypertension in rats. Methods: a total of 82 rats in reproductive age were used. They were randomly assigned to 4 different groups (control, handled, nephrectomy and hypertension) and renal hypertension was produced by a controlled constriction of the main left renal artery, according to the technique described by Goldblatt, and contralateral nephrectomy (Goldblatt I one kidney–one clip model). Furthermore, they were distributed into non-pregnant groups and pregnant (P) groups. From the pregnant groups, the following newborn groups were obtained: RN-C (control — newborn group from the pregnant rats without surgical treatment), RN-M (manipulation — newborn group from the pregnant rats with surgical manipulation), RN-N (nephrectomy — newborn group from the pregnant rats with nephrectomy) and RN-H (hypertension — newborn group from pregnant rats with hypertension). Results: the RN-C newborn group ( = 0.58 ± 0,12) showed placental weight higher than the other three groups (RN-M: or = 0.51 ± 0.05; RN-N: or = 0.45 ± 0.07 and RN-H: or = 0.42 ± 0.04). On the other hand, it was possible to observe that the placental weight of the RN-M was higher than that of RN-N and RN-H, respectively, but no difference was observed between the RN-N and RN-H groups. The placental index showed no difference between P-C (Md = 0.1085) and P-M (Md = 0.1110), and also between P-N (0.1175) and P-H (0.1211), but it was observed that the placental indexes of P-C and P-M were smaller that those of P-N and P-H. Conclusion: unilateral nephrectomy and hypertension determined a reduction in placental weight and an increase in the placental index, showing a repercussion regarding placental and fetal development.