[Production and localization of human prolactin in the tissues associated with pregnancy (Report I) (author's transl)].

In the present paper, the authors studied the production and localization of human prolactin from normal human chorionic tissue and decidua in early pregnancy (from the 7th to the 9th week after last menstruation) obtained either by curettage or hysterectomy. Immunohistological investigation by the fluorescent antibody technique using human prolactin specific antiserum prepared by the immunization of rabbits revealed that syncytial trophoblast was a production site of prolactin. Though prolactin was recognized in compact layers of parietal decidua, it was concerned not with production but solely with deposition in intercellular space which was widened edematously with the existence of a collagen-like substance. By double staining method of the fluorescent antibody technique, prolactin could be differentiated with both hCG and hPL in syncytial trophoblast.