Molecular Human Reproduction Vol. 1, NUMBER 1 pp. 21-29, 1995
© European Society of Human Reproduction and Embryology 1995
research-article |
Hormonal regulation of tissue-type plasminogen activator and plasminogen activator inhibitor type-1 in cultured monkey Sertoli cells
1State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences Beijing 100080 2Primate Research Center, Kunming Institute of Zoology Kunming 650223, China 3Present address: Department of Medical Biochemistry. Umeå University S-90187 Umeå, Sweden 4Present address: Department of Pathology, McMaster University Hamilton, Ontario L8N 3Z5, Canada
To whom correspondence should be addressed at: 5To whom correspondence should be addressed at:Department of Endocrinology, Institute of Zoology, 19 Zhongguancun Lu, Haidian, Beijing 100080, China
Sertoli cells play a central role in the control and maintenance of spermatogenesis. Isolated Sertoli cells of mouse and rat testes have been shown to secrete plasminogen activator (PA) and a plasminogen activator inhibitor type-1 (PAI-1) in culture. In this study, we have investigated the hormonal regulation of PA and PAI-1 activities in cultured monkey Sertoli cells. Sertoli cells (5x105 cells/well) isolated from infant rhesus monkey testes were preincubated at 35°C for 16 h in 24-well plates precoated with poly(D-lysine) (5 µg/cm2) in 0.5 ml McCoy's 5a medium containing 5% of fetal calf serum and further incubated for 48 h in 0.5 ml serum-free medium with or without various hormones or other compounds. PA as well as PAI-1 activities in the conditioned media were assayed by fibrin overlay and reverse fibrin autography techniques respectively. The Sertoli cells in vitro secreted only tissue-type PA (tPA), no detectable amount of urokinase-type PA (uPA) could be observed. Monkey Sertoli cells were also capable of secreting PAI-1. Immunocytochemical studies indicated that both tPA and PAI-1 positive staining localized in the Sertoli cells, spermatids and residual bodies of the seminiferous epithelium; Northern blot analysis further confirmed the presence of both tPA and PAI-1 mRNA in monkey Sertoli cells. Addition of follicle-stimulating hormone (FSH) or cyclic adenosine monophosphate (cAMP) derivatives or cAMP-generating agents and gonadotrophin-releasing hormone (GnRH) agonist or phorbol ester (PMA) to the cell culture significantly increased tPA activity. PAI-1 activity in the culture was also enhanced by these reagents except 8-bromo-dibutyryl-cAMP, forskolin and 3-isobutyl-1-methylxanthin (MIX) which greatly stimulated tPA activity, whereas decreased PAI-1 activity, implying that neutralization of PAI-1 activity by the high level of tPA in the conditioned media may occur. These data suggest that increased intracellular signals which activate protein kinase A (PKA), or protein kinase C (PKC) can modulate Sertoli cell tPA and PAI-1 activities. The concomitant induction of PA and PAI-1 by the same reagents in the Sertoli cells may reflect a finely tuned regulatory mechanism in which PAI-1 could limit the excession of the proteolysis.
plasminogen activator inhibitor type-1/Rhesus monkey/Sertoli cells/tissue-type plasminogen activator