HORMONAL-REGULATION OF TISSUE-TYPE PLASMINOGEN-ACTIVATOR AND PLASMINOGEN-ACTIVATOR INHIBITOR TYPE-1 GENE-EXPRESSION IN CULTURED MOUSE SERTOLI CELLS

We have demonstrated for the first time that (i) mouse Sertoli cells p redominantly secrete tPA under the action of FSH and cAMP-generating a gents, whereas Leydig cells mainly produce uPA; (ii) Sertoli cells are also capable of secreting PAI-1, as well as FSH, growth factors and G nRH increase PAI-1 gene expression; (iii) the increases in tPA and PAI -1 activities by different hormones in the conditioned media of Sertol i cells correspond to the increases in the levels of tPA and PAI-1 mRN A in the cultured cells, suggesting that the synthesis of the activato r-inhibitor in mouse Sertoli cells is regulated at a transcriptional l evel and the tPA secreted by Sertoli cells may be involved in the sper matogenesis.