AIMTo evaluate the effect of a protein synthesis inhibitor cycloheximide on arresting activity in spermatogenesis and sperm count in male rats.

METHODSThe study used seminiferous tubule (ST) segments from adult rats cultured in vitro with or without cycloheximide to condition culture media, which have been concentrated, size fractioned (30-50 kDa) and administered 7 days to adult rats by intraperitoneal injections. The effects on testicular and epididymal weights, spermatogenesis and epididymal sperm count were determined.

RESULTSThe fraction (30-50 kDa), named arresting, obtained from the culture without cycloheximide decreased testicular and epididymal weights (P<0.01) and reduced the epididymal sperm count significantly. Study of the spermatogenic cycle by transillumination showed spermatogenic arrest at stage VII in rats treated with arresting compared to that observed in controls. The length of stage VII in the group receiving the seminiferous tubules culture media with cycloheximide (30-50 KDa CHX-STCM fraction) was similar to control.

CONCLUSIONThe difference in the effect may be the result of the presence or absence of arresting, a protein secreted by the tubules.

Animals ; Arrestin ; biosynthesis ; Culture Media, Conditioned ; Cycloheximide ; pharmacology ; Epididymis ; cytology ; drug effects ; growth & development ; Male ; Protein Synthesis Inhibitors ; pharmacology ; Rats ; Seminiferous Epithelium ; cytology ; drug effects ; physiology ; Seminiferous Tubules ; metabolism ; Sperm Count ; Testis ; drug effects ; growth & development