Regulation of mouse placental lactogen-II secretion by transforming growth factor-alpha after midpregnancy.
We investigated whether transforming growth factor-alpha (TGF-alpha) regulates mouse placental lactogen-II (mPL-II) secretion by cells from day 12 of pregnancy. TGF-alpha significantly inhibited mPL-II secretion by the third and fourth day of culture, and then stimulated mPL-II secretion from the sixth day. The inhibitory and stimulatory effects of TGF-alpha on mPL-II secretion were dose-dependent, and the lowest concentration of TGF-alpha-which caused significant inhibition or stimulation of mPL-II secretion was 10 ng/ml. When TGF-alpha treatment of placental cells was begun on the fifth day of the culture, significant stimulation of mPL-II secretion was observed 3 days later. TGF-alpha inhibited steady-state levels of mPL-II mRNA on the third day of culture but stimulated steady-state levels of mPL-II mRNA on the seventh day of culture. These results suggest that TGF-alpha biphasically regulates mPL-II secretion through regulation of mPL-II gene expression after midpregnancy.
Yamaguchi
M
M
Department of Obstetrics and Gynecology, Osaka University Medical School, Japan.
Kobayashi
K
K
Miyake
A
A
D000818:Animals; D015152:Blotting, Northern; D002478:Cells, Cultured; D005260:Female; D051379:Mice; D008813:Mice, Inbred ICR; D010920:Placenta / Q000378:metabolism*; D010928:Placental Lactogen / Q000235:genetics / Q000378:metabolism*; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors; D016211:Transforming Growth Factor alpha / Q000494:pharmacology*
D012333:RNA, Messenger; D016211:Transforming Growth Factor alpha; C062303:placental lactogen II; D010928:Placental Lactogen