RESIDUAL BODIES STIMULATE RAT SERTOLI-CELL PLASMINOGEN-ACTIVATOR ACTIVITY

Previous studies suggested indirectly that residual bodies (RB) may pl ay a role in the regulation of the proteolytic system within the testi s and in the coordination of the spermatogenetic process. In the prese nt study, we examined the effects of RE recovered from adult rat teste s by centrifugal elutriation on Sertoli cell plasminogen activator (PA ) levels, by zymography and ELISA procedures. Addition of RE to Sertol i cell cultures prepared from 20-day-old rat testes resulted in a dram atic stimulation of PA. Effects were dose- and time-dependent, Phagocy tosis of RE by Sertoli cells leads to a rapid stimulation of Sertoli c ell interleukin-1 alpha (IL-1 alpha), a cytokine potentially involved in the regulation of spermatogenesis; the effects of IL-1 alpha were i nvestigated. We found that IL-1 alpha augmented PA levels and that imm unodepletion of Sertoli cell-RE cocultures with anti-IL-1 alpha antibo dies abrogated the stimulatory effects of RE on PA. Together, the pres ent findings indicate that RE enhance Sertoli cell PA and that IL-1 al pha may be involved in that control. (C) 1998 Academic Press.