Factors of the plasminogen activator system in human testis, as demonstrated by in-situ hybridization and immunohistochemistry

4 To whom correspondence should be addressed A growing body of evidence suggests that the plasminogen activator (PA) system is crucially involved in reproductive physiology in both sexes. Certain factors of the PA system have been found to be present in organs of the male reproductive tract in various species, and the presence of several of the factors was recently demonstrated in monkey testis. The present morphological study was therefore designed to investigate the occurrence and distribution of the tissue and urokinase plasminogen activators (t-PA and u-PA), the u-PA receptor (u-PAR) and the plasminogen activator inhibitors (PAI-1 and PAI-2) in normal human testis. Intraoperative specimens from seven patients undergoing orchidectomy or testicular biopsy were studied using in-situ hybridization (ISH) and immunohistochemistry (IHC). All five factors studied could be detected with both the ISH and IHC procedures. The ISH signals were localized to sites in the testicular tubules in a stage-specific manner. There was good correlation between results obtained with the two methods, though in IHC the tubules were stained more uniformly. The findings provide support for the involvement of the PA system in human male reproductive physiology.