Mouse placental cells secrete soluble leptin receptor (sOB-R): cAMP inhibits sOB-R production.
The aims of this study were to identify whether mouse placenta secretes soluble OB-R (sOB-R) and to find the regulating factor of OB-R expression. Total RNAs were extracted from placenta and decidua, and OB-R expression was assessed by Northern blot analysis. Decidua did not express OB-R mRNA. However, OB-R mRNA expression was detectable in the placenta on day 13 of pregnancy, and then it increased and reached a peak on day 17 of pregnancy. Mouse placental cells from day 12 of pregnancy were cultured and OB-R gene expression was assessed by Northern blot analysis. OB-R mRNA expression was detectable from the second day of culture and reached a peak on the third day of culture. To determine whether placental cells release sOB-R, supernatant of cultured placental cells was subjected to Western blot analysis. sOB-R was detected in the medium by the second day of culture and sOB-R release increased up to the fourth day of culture. Addition of leptin to the medium did not affect expression of OB-R mRNA. However, 8-bromo cAMP inhibited both steady-state levels of OB-R mRNA and the amount of sOB-R protein in the medium in a dose- and time-dependent manner. These results suggest that trophoblast cells differentiate, express, and release sOB-R both in vivo and in vitro and that cAMP is one of several potent regulators of sOB-R secretion by the mouse placenta.
Yamaguchi
M
M
Department of Obstetrics and Gynecology, Osaka University Medical School, Suita, 565-0871, Japan.
Murakami
T
T
Yasui
Y
Y
Otani
S
S
Kawai
M
M
Kishi
K
K
Kurachi
H
H
Shima
K
K
Aono
T
T
Murata
Y
Y
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D020738:Leptin; D051379:Mice; D010920:Placenta / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D011506:Proteins / Q000378:metabolism / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin; D012995:Solubility
D002352:Carrier Proteins; D020738:Leptin; D011506:Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin; C515447:leptin receptor, mouse; D015124:8-Bromo Cyclic Adenosine Monophosphate; D000242:Cyclic AMP