Inhibition of intratesticular testosterone synthesis by inorganic lead.

The alterations in testicular testosterone synthesis produced by exposure to inorganic lead were investigated in BALB/c+ mice. Lead concentration in blood and testes and the levels of testosterone and delta 4-androgen biosynthesis pathway precursors (4-androstenedione, 17-hydroxyprogesterone, and progesterone) were measured in animals which were exposed to lead acetate in the drinking water (366 mg/l, 0.97 +/- 0.12 mg lead/animal/day) during 6 months. The results showed a significant reduction of the intratesticular testosterone levels after 30 days of exposure and of the androstenedione levels after 150 days. Intratesticular progesterone and hydroxyprogesterone levels showed no changes during the assay.