Inhibition of mouse placental lactogen-II release from placental cells by interleukin-1 after mid-pregnancy.
The effects of interleukin (IL)-1 and granulocyte-macrophage colony stimulating factor (GM-CSF), which are present in the mouse placenta, on the secretion of mouse placental lactogen (mPL)-1 and mPL-II by placental cells were tested in vitro. IL-1 alpha and IL-1 beta, 2.5 nmol/l each, significantly inhibited mPL-II secretion by cells from days 9 and 12 of pregnancy, but did not affect mPL-II secretion by cells from day 7 of pregnancy or mPL-I secretion by cells from days 7, 9 or 12 of pregnancy. GM-CSF had no effect on mPL-I and mPL-II secretion by cells from days 7, 9 or 12 of pregnancy. The inhibitory effects of IL-1 alpha and IL-1 beta on mPL-II secretion were completely eliminated by the addition of antibodies to IL-1 alpha and IL-1 beta respectively. Western blot analysis for mPL-II indicated that IL-1 alpha significantly reduced the intensity of the mPL-II band. Steady-state levels of mPL-II mRNA, assessed by Northern blot analysis, were reduced by incubation of placental cells from day 12 of pregnancy with 2.5 nmol/l IL-1 alpha for 5 days. Co-incubation of 0.25 pmol/l IL-1 alpha, 25 pmol/l IL-6, and 25 pmol/l tumor necrosis factor-alpha, each of which did not significantly inhibit mPL-II secretion by itself, together inhibited mPL-II secretion. These results suggest that IL-1, but not GM-CSF, is a potent inhibitor of mPL-II secretion after mid-pregnancy, and that the combined action of cytokines can inhibit mPL-II secretion.
Yamaguchi
M
M
Department of Obstetrics and Gynecology, Osaka University Medical School, Japan.
Sakata
M
M
Ogura
K
K
Adachi
K
K
Mammoto
A
A
Miyake
A
A
D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D002478:Cells, Cultured; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000378:metabolism / Q000494:pharmacology; D007375:Interleukin-1 / Q000378:metabolism* / Q000494:pharmacology; D051379:Mice; D008813:Mice, Inbred ICR; D010920:Placenta / Q000378:metabolism*; D010928:Placental Lactogen / Q000235:genetics / Q000378:metabolism*; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D011863:Radioimmunoassay
D007375:Interleukin-1; D012333:RNA, Messenger; C062303:placental lactogen II; D016179:Granulocyte Colony-Stimulating Factor; C085699:placental lactogen I, rat; D010928:Placental Lactogen