Prolactin stimulates proliferation of cultured human keratinocytes.
The effect of the pituitary hormone prolactin on in vitro proliferation of human keratinocytes has been studied. Cell proliferation was determined by [3H] thymidine incorporation and cell enumeration in culture. Physiologic concentrations of prolactin markedly stimulated proliferation of newborn foreskin keratinocytes in serum-free medium. In addition, it was able to replace almost completely the growth-promoting effects of bovine pituitary extract, a commonly added supplement for keratinocyte culture. This activity was also evident in the absence of epidermal growth factor, but required the presence of insulin. Radioligand-binding studies confirmed the expression of specific prolactin binding sites (Kd 8.9 nM; 1350 sites per cell) on freshly procured keratinocyte membranes. These results extend its hormonal influences to include regulation of in vitro proliferation of human keratinocytes, and suggest the possibility of a completely defined growth medium for keratinocytes.
Department of Dermatology, University of Texas Southwestern Medical Center, Dallas 75235.
G
G
Girolomoni
J T
JT
Phillips
P R
PR
Bergstresser
D001665:Binding Sites; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D006801:Humans; D007231:Infant, Newborn; D015603:Keratinocytes / Q000166:cytology*; D008297:Male; D011388:Prolactin / Q000494:pharmacology*; D011981:Receptors, Prolactin / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism; D014316:Tritium
D016895:Culture Media, Serum-Free; D011981:Receptors, Prolactin; D014316:Tritium; D011388:Prolactin; D013936:Thymidine