Plasminogen activator inhibitor-1 is expressed in cultured rat Sertoli cells
Plasminogen activator inhibitor-1 is expressed in cultured rat Sertoli cells
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DOI：
10.1095/biolreprod59.3.591
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发表时间：
1998-09-01
影响因子：
3.6
通讯作者：
Benahmed, M
中科院分区：
文献类型：
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作者：
Le Magueresse-Battistoni, B;Pernod, G;Benahmed, M
支持细胞在血-睾丸屏障的两侧分泌纤溶酶原激活物（PA），即，在生精小管的基底和顶室中，而管周细胞分泌纤溶酶原激活物抑制剂-1（派-1），一种快速作用和特异性PA抑制剂。虽然可能是由管周细胞产生的派-1抵消PA的基础分泌，PA抑制剂在顶室中起作用的性质仍有待证明。在本研究中，我们发现，从20日龄大鼠中回收并培养的支持细胞含有3-3.2磷酸酶的转录本，其与派-1 cDNA探针特异性杂交（北方印迹）。我们通过比较从20日龄大鼠中回收并培养的支持细胞和管周细胞的派-1 mRNA水平，证实了所观察到的PAI-1转录物不能仅来自管周细胞（轻微污染支持细胞培养物）。我们还证明，培养的支持细胞分泌的蛋白质，与组织型PA（酶谱），表明它是生物活性的复合物。该蛋白与纯化的派-1共迁移，为46和49 kDa的双联体（Western blot）。营养激素FSH降低派-1信使RNA以及免疫反应性派-1蛋白（可能通过cAMP蛋白激酶A途径），而转化生长因子β 1和碱性成纤维细胞生长因子（纳摩尔浓度）增加这两种。这些观察结果支持了派-1由支持细胞表达并且处于至少由碱性成纤维细胞生长因子和转化生长因子β 1施加的复杂激素（FSH）和旁分泌和/或自分泌控制下的假设。
Sertoli cells secrete plasminogen activators (PAs) on both sides of the blood-testis barrier, i.e., in the basal and apical compartments of the seminiferous tubules, whereas peritubular cells secrete plasminogen activator inhibitor-1 (PAI-1), a fast-acting and specific PA inhibitor. While it is likely that PAI-1 produced by peritubular cells counteracts the basal secretion of PA, the nature of the PA inhibitor acting in the apical compartment remains to be demonstrated. In the present study, we showed that Sertoli cells recovered from 20-day-old rats and cultured contained a transcript of 3-3.2 kilobases, which hybridized specifically to a PAI-1 cDNA probe (Northern blot). We verified that the observed PAI-1 transcript could not result solely from the peritubular cells (weakly contaminating the Sertoli cell cultures), by comparing PAI-1 mRNA levels of Sertoli and peritubular cells recovered from 20-day-old rats and cultured. We also demonstrated that cultured Sertoli cells secreted a protein that complexed with tissue-type PA (zymography), indicating that it was biologically active. This protein comigrated with purified PAI-1 as a doublet of 46 and 49 kDa (Western blot). The trophic hormone FSH decreased PAI-1 messenger RNA as well as immunoreactive PAI-1 protein (probably via the cAMP protein kinase A pathway), whereas transforming growth factor beta 1 and basic fibroblast growth factor (in a nanomolar concentration) increased both of these. These observations support the hypothesis that PAI-1 is expressed by Sertoli cells and is under a complex hormonal (FSH) and paracrine and/or autocrine control exerted at least by basic fibroblast growth factor and transforming growth factor beta 1.