Abstract
The ability of androgen pretreatment in adult Wistar rats to protect the spermatogonial stem cells from one or two doses of the cytotoxic procarbazine (PCB) was investigated. Survival of stem cells was assessed by a tubule regeneration assay. Ten weeks' pretreatment of the rats with 200 mm2 silastic implants containing testosterone resulted in significant protection of the spermatogonial stem cells from PCB-induced damage. Androgen-pretreated rats given a single dose of 200 mg/kg PCB demonstrated 86% tubule regeneration as opposed to 41% in rats pretreated with cholesterol. Similar values were obtained when the PCB dose was given as two weekly fractions of 100 mg/kg. The protective effect of androgen is present from the time of the initial challenge with the cytotoxic drug.