Expression of insulin-like growth factor-II and its mRNA in PIH Placenta

Objective To investigate the expression of insulin-like growth factor-Ⅱ( IGF-II ) and its mRNA in human placenta and to evaluate its role in the pathogenesis pregnancy induced hypertension (PIH). Methods The cellular distribution of IGF-Ⅱin normal and PIH placenta was determined by immunohistochemistry. Trophoblasts were digested,separated,and purified from placenta. IGF-ⅡmRNA expression in trophoblasts was detected by RT-PCR. The mean density was determined by image analysis technique. Results (1) IGF-Ⅱwas mostly found in syncytiotrophoblast,cytotrophoblast and amnio-chorion. The strongest immunoreactivity was observed in the syncytiotrophoblast and cytotrophoblast. (2)The mean density of PIH placenta (0.324±0.042) was significantly lower than that of normotensives (0.360±0.072,P 0.05). (3)The expression of IGF-ⅡmRNA in PIH trophoblasts (0.72±0.72)was significantly lower than that of control group(0.96±0.30,P 0.05). Conclusion IGF-Ⅱin human placenta was mainly synthesized and secreted by syncytiotrophoblast,cytotrophoblast. Reduced IGF-Ⅱexpression may have an important role in the pathogenesis in PIH.