Human dermal fibroblast cells express prolactin in vitro.
This study demonstrates the synthesis and release of prolactin (PRL) from dermal fibroblasts (>98%) in vitro, suggesting a potential local source of PRL in skin. PRL release was first detected in confluent cultures (0.25 x 10(6) plated cells) on or before day 18 and increased to a maximal level of 2 ng/72 h by day 30. Medroxyprogesterone acetate and estradiol (E2) had no effect on PRL release, but prostaglandin E2 (PGE2) reduced the time required for PRL induction to 6-9 days. The steroids and PGE2 together were synergistic, reaching maximal values of approximately 10 ng/72 h after 2 or more weeks of treatment. Dibutyryl-cyclic AMP, a second messenger in prostaglandin signal transduction, was also synergistic with medroxyprogesterone acetate and E2, but induced significant PRL expression in the absence of the steroids (28 and 12 ng/72 h, respectively). The increase in PRL release was not a result of increased cell proliferation, because the PRL-secreting cultures had 32.2 +/- 8.8% less DNA (N = 3 individuals, 93% confidence limit) than control cultures after 3 weeks of treatment with dibutyryl-cyclic AMP, medroxyprogesterone acetate, and E2. Dermal fibroblast PRL was immunologically and electrophoretically identical to decidual and pituitary PR-Ls, and Northern blot analysis demonstrated a PRL mRNA size of 1.15 kb. Maximal PRL release from fibroblast cells was 32.0 +/- 6.1 ng/72 h (mean +/- SD at 95% confidence limit) for a donor population representing both males (n = 15) and females (n = 7) between the ages of 20-week gestation to 52 years. In contrast to term decidual fibroblast cells that also express PRL, dermal fibroblasts did not co-express insulin-like growth factor-binding protein-1.
Richards
R G
RG
Children's Hospital, Cincinnati, Ohio, USA.
Hartman
S M
SM
D015153:Blotting, Western; D003994:Bucladesine / Q000494:pharmacology; D002478:Cells, Cultured; D003656:Decidua / Q000378:metabolism; D015232:Dinoprostone / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000378:metabolism; D017258:Medroxyprogesterone Acetate / Q000494:pharmacology; D010902:Pituitary Gland / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism*; D012867:Skin / Q000166:cytology / Q000378:metabolism*
D018970:Insulin-Like Growth Factor Binding Protein 1; D004958:Estradiol; D003994:Bucladesine; D011388:Prolactin; D017258:Medroxyprogesterone Acetate; D015232:Dinoprostone