The action of triethylenemelamine on the fertility of male rats.

Small doses of triethylenemelamine (TEM) had a selective action on the fertility of male rats. One dose (0.2 mg./kg., i.p.) produced effects ranging from subfertility to sterility during the next 3 weeks. In the fourth week sterility was the rule, but normal fertility was restored in the fifth week. A short course of the drug (5 daily doses, 0.2 mg./kg., i.p.) resulted in sterility lasting about 5 weeks, after which fertility was rapidly regained. Daily doses (0.05 mg./kg., i.p.) caused infertility in about a week which was maintained throughout treatment (7 weeks), and persisted for several weeks after the drug was discontinued. Sexual activity of infertile animals seemed normal and sperm production appeared to continue. Spermatozoa from infertile animals were able to reach and penetrate ova. The results suggest that TEM acts directly on the germinal epithelium. An attempt has been made to provide some explanation for these results and correlate them with the time required for spermatogenesis.