停留睾丸のandrogen生合成能 (生化学的生検法の適応)

Abstract

In order to evaluate the feasibility of utilizing small amount of testicular tissues for the study of androgens biosynthesis in vitro, testicular tissues were obtained from adult patients with cryptorchidism at the time of therapeutic orchiectomy. Various amounts of testicular tissue ranging from 10 to 100 mg were incubated with progesterone-3H and the formation of radioactive androgens was calculated and thus the conversion rates of androgens from progesterone were compared each other. From these experiments, it was demonstrated that testicular tissue under 50 mg was enough to study biosynthetic pathway from progesterone to testosterone and these amounts of tissue were easily obtained from surgical biopsy. As the second step, androgens biosynthesis was studied on 23 testicular biopsy speciemens taken from 15 cryptorchid testes and 8 contralateral intrascrotal testes using above mentioned method. The ages of the patints ranged from 2 to 13. It was noted that the conversion rates to testosterone of cryporchid testes in under 4, 5-10, 11-13 age groups were 0.67±0.24 %, 1.15±1.20 %, and 6.43±3.08 %, respectively. On the other hand, the conversion rates of the contralateral intrascrotal testes in the above mentioned age groups were 0.45±0.02 %, 5.05±0.73 %, and 17.00±0.00 %, respectively. In summary, it was clearly demonstrated that the great difference of conversion rates began at the age of 5.