[Dynamics of various peptide hormone receptors in human placental cell membranes]

The action of peptide hormone receptors on the cell membranes and the cyclic-AMP in its post receptor system dynamics was studied. [Results] Receptors for hCG-LH, hPL-hGH, ACTH and Insulin were found in the placental cell membranes but receptors for FSH and PRL were not found. The possibility was suggested that the cyclic-AMP was the second messenger in the receptor system for hCG-LH, hPL and ACTH. The differences between normal placental cell membranes and hydatidiform mole were studied from the point of view of the receptor level. Receptors on molar trophoblast for hCG-LH, hPL-hGH and ACTH increased about two fold to three fold over those on normal trophoblast. The presence of receptors for hCG-LH, hPL and ACTH was confirmed also in GCH-1 (gestational choriocarcinoma cell line). The possibility is shown that the placenta has an auto regularity system in its own tissue throughout the various peptide hormones receptors such as hCG-LH and hPL.