[The effect of perorally administered DDVP and malathion on spermatogenesis and Leydig cells in the juvenile rat].

Immature male rats receive orally DDVP 20 mg/kg on the 4th and 5th resp. 10 mg/kg on the 4th to the 24th day of life or malathione 40 resp. 20 mg/kg. At defined days the testes are examined histologically. The body weight does not change. The testis weight, tubular diameter, number of Sertoli cells, and of A-spermatogonia per tubular cross section as well as the number of Leydig cells is diminished. Malathione produced more severe alterations, they disappear, however, until the 50th day of life. Refering to the metabolic mechanisms of both the phosphatic esters a local lack of testosterone causing the disturbances is discussed.