Release of prorenin and placental hormones from superfused minced chorion laeve

Subject. Prorenin, the biosynthetic precursor of renin, is present in organs of the human reproductive system. Method and material. In this study we tested whether the release of prorenin from superfused minced human chorion laeve tissue is related to that of other placental hormones. We also investigated whether intracellular second messenger systems are involved in the prorenin release from placental tissue. Results. More than 95% of the total renin released was in the form of prorenin. The release pattern of human chorionic gonadotropin (hCG), estradiol and progesterone was similar to that of prorenin. Exogenous hCG, the estrogen receptor blocker tamoxifen and the progesterone receptor blocker RU 486, 8‐bromo cyclic AMP, diltiazem and angiotensin II did not affect prorenin release. Conclusion. We conclude that prorenin, not active renin, is released from placental cytotrophoblastic tissue. This release occurs in parallel to that of other placental hormones but it is not regulated by steroid receptors, hCG, intracellular calcium or cyclic AMP.