As an extension of our studies on the influence of age on testicular function and with the aim of detecting whether the decline in testosterone production by aged testes is accompanied by a block in the biosynthetic chain leading from cholesterol to testosterone, we determined in the testis of young and elderly men, who died suddenly either from a cardiac incident or from accident, intratesticular steroids: pregnenolone, 17 hydroxypregnenolone (3β, 17α-dihydroxy-5-pregnen-20-one), dehydroepiandrosterone, androstenediol, (5-androsten-3β, 17β-diol), progesterone, 17 hydroxyprogesterone, androstenedione, 17β-estradiol as well as testosterone, dihydrotestosterone (5α-androstan-17β-ol-3-one) and androstanediol (5αandrostane-3α, 17β-diol). The intratesticular steroid pattern in elderly men was essentially characterized by a decrease of the 5-ene steroid concentration, whereas we did not observe a decrease in the 4-ene steroids, progesterone concentration being even significantly higher in the aged testes. There was no evidence for a decrease in either lyase or 17-hydroxylase activity. It is suggested that the steroid pattern as observed in the aged testes is the consequence of a decreased oxygen supply, due to a decreased testicular perfusion.
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