The Expression of Corticotropin-Releasing Hormone Gene and its Immunohistochemical Analysis in Human Trophoblast of Normal Pregnancy and Trophoblastic Disease

Abstract

Immunoreactive corticotropin-releasing hormone (IR-CRH) in maternal plasma increases progressively with pregnancy and rapidly declines after delivery. So the production site of IR-CRH is thought to be placenta. We studied the expres sion of CRH gene and its immunohistochemical localization in human developing chorionic tissue, amniotic membranes, uterine myometrium and fresh surgical speci men of hydatidiform mole with the methods of Northern blotting and avidin-biotin complex staining. The results are 1) the CRH mRNA were identified in third trimes ter and term placentae, but could not be demonstrated in first and second trimesters placentae, 2) the CRH mRNA expresses in amniotic membranes but not in myomet rium of normal term pregnancy, 3) IR-CRH localization was demonstrated in the cytotrophoblast of placenta and decidua of first trimester, and in the amniotic membranes of term pregnancy and, 4) the CRH mRNA and its immunohistochemical localization was not detected in trophoblast of hydatidiform mole. These results sug gest that the sources of increased IR-CRH in human plasma and amniotic fluid during pregnancy are placenta, decidua and amniotic membranes, and that the gene expression and secretion / storage ratio of placental CRH increases as pregnancy advances. The expression in trophoblast of hydatidiform mole may be suppressed because of the characteristic change of trophoblast. (Thai J Obstet Gynaecol 1991;3: 21-30.)