Relationship between imbalanced synthesis of human chorionic gonadotropin alpha and beta subunits and pregnancy-induced hypertension

Abstract

To study the relationship between imbalanced synthesis of human chorionic gonadotropin (hCG) alpha and beta subunits and the pathology of pregnancy-induced hypertension (PIH). Total hCG, free alphahCG and betahCG were measured in serum samples collected from 60 cases of PIH and 30 normal gravid women by radioimmunoassay. The ratio of total hCG/betahCG, betahCG/FalphahCG, (FalphahCG+betahCG)/betahCG were calculated. Immunohistochemical staining was performed in 13 placenta from each group. In PIH group the levels of FalphahCG, total hCG and betahCG were significantly higher than those of normal group (FalphahCG: 528 +/-421 IU/L compared with 222 +/-129 IU/L; betahCG: 39396 +/-6412 IU/L compared with 24265 +/-5575 IU/L; total hCG: 66597 +/-9294 IU/L compared with 36078 +/-4767 IU/L, all P<0.001). The betahCG/FalphahCG ratio in PIH was lower than that of normal group (91.23 +/-53.38 Compared with 119.4 +/-80.1, P<0.05); (FalphahCG+betahCG)/betahCG ratio and total hCG/betahCG ratio in two groups were (1.022 +/-0.026 compared with 1.015 +/-0.011; 1.802 +/-0.339 compared with 1.807 +/-0.258, respectively P>0.05). The immunohistochemical intensity of betahCG and FalphahCG in syncytiotrophoblast was significantly increased in 13 PIH compared with the control. These data suggested that the imbalanced synthesis of hCG alpha and beta subunits may cause hypertension.