Prolactin inhibition of FSH-induced tissue type plasminogen activator expression in cultured rat granulosa cells.
This study was designed to investigate whether prolactin (PRL) affects coordinated regulation of tissue plasminogen activator (tPA) and plasminogen activator inhibitor type-I(PAI-I) gene expression in rat granulosa cells in vitro. Several methods, such as SDS-PAGE, immunoblot etc. were used to detect the effect of PRL on tPA and PAI-I gene expression. The results demonstrated: (1) PRL increases PAI-I mRNA production in cultured granulosa cells. Inclusion of follicle stimulating hormone (FSH) with PRL has a synergistic effect on the increase of PAI-I mRNA levels. After 48 h culture in the presence of FSH with PRL, a 7.8-fold increase in PAI-I mRNA levels is observed as compared with PRL alone. The synergistic increase in PAI-I mRNA levels occurs in a dose- and time-dependent manner; (2) the increase in PAI-I mRNA synthesis in the cells by PRL alone, or PRL in combination with FSH, is well correlated with the changes of PAI-I activity levels in the conditioned media; (3) PRL in culture also decreases FSH-induced tPA activity level in a dose-dependent fashion. The decrease in FSH-induced tPA activity level by PRL is correlated with an increase in the amount of PA-PAI-I complexes in the conditioned media. This suggests that the decline of tPA activity is related to neutralization of tPA by the increased PAI-I activity in the media.
Liu
Y X
YX
State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080. Liuyx@panda.ioz.ac.cn
Liu
H Z
HZ
Chen
Y J
YJ
Tor
N Y
NY
D000818:Animals; D002478:Cells, Cultured; D005260:Female; D005640:Follicle Stimulating Hormone / Q000037:antagonists & inhibitors*; D015870:Gene Expression; D006107:Granulosa Cells / Q000378:metabolism*; D006080:Ovarian Follicle / Q000378:metabolism; D017395:Plasminogen Activator Inhibitor 1 / Q000096:biosynthesis* / Q000235:genetics; D011388:Prolactin / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D010959:Tissue Plasminogen Activator / Q000096:biosynthesis* / Q000235:genetics
D017395:Plasminogen Activator Inhibitor 1; D012333:RNA, Messenger; D011388:Prolactin; D005640:Follicle Stimulating Hormone; D010959:Tissue Plasminogen Activator