title: Modulation of prolactin secretion in human myometrium by cytokines.
abstract: Prolactin (PRL) secretion and PRL mRNA expression in human myometrial explant cultures was inhibited by the addition of human placental conditioned medium (HPCM). After 3 days treatment with 5% HPCM PRL secretion was reduced to 24% of control values (P < 0.001). The effect persisted even after removal of progesterone, which suppresses myometrial PRL production, from the HPCM. In search for additional regulatory substances present in the uteroplacental unit, we tested a number of growth factors and cytokines known to affect pituitary PRL secretion. Treatment with endothelin-3 (ET-3) at a dose of 10(-6) M was found to increase PRL release by 20% over 3 days (P < 0.05) whereas interleukin-6 (IL-6) showed no effect on PRL levels. Epidermal growth factor, vasoactive intestinal peptide and interferon-alpha (IFN-alpha) were inhibitory. Interleukin-4 (IL-4) was the most potent inhibitor of PRL expression in myometrial tissue, causing a reduction of secreted PRL to less than 50% of controls after 3 days at a dose of > or = 5 ng/ml (P < 0.001) and a concomitant reduction of PRL mRNA levels. These results demonstrate a modulation of PRL expression in the myometrium by locally present factors.
authors.affiliation: Institute for Hormone and Fertility Research, Hamburg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Bonhoff
authors.forename: B
authors.initials: B
authors.lastname: Gellersen
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D016207:Cytokines / Q000494:pharmacology*; D016232:Endothelins / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005260:Female; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D008875:Middle Aged; D009215:Myometrium / Q000378:metabolism*; D010920:Placenta / Q000502:physiology; D011388:Prolactin / Q000378:metabolism*; D011994:Recombinant Proteins; D013997:Time Factors; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
chemical_list: D017077:Culture Media, Conditioned; D016207:Cytokines; D016232:Endothelins; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D015850:Interleukin-6; D011994:Recombinant Proteins; D015847:Interleukin-4; D014660:Vasoactive Intestinal Peptide; D004815:Epidermal Growth Factor; D011388:Prolactin