Testosterone metabolism by proximal and distal regions of the vas deferens from immature and mature rats
The vas deferens, an androgen-dependent organ, may have physical importance in sperm maturation, yet very little is known about its steroid capabilities. To explore the steroid metabolic activities and their possible changes during sexual maturation, a comparative study of /sup 14/C testosterone metabolism by the proximal (VDP) and distal (VDD) segments of the vas deferens from immature and mature rats was carried out in vitro. Approximately 50 mg of the VDP and VDD portions of the vas deferens, devoid of spermatozoa, were incubated in duplicates for 3 h at 37 degrees C with /sup 14/C testosterone (53.5 microCi/mmol) and the essential cofactors. After the addition of appropriate /sup 3/H-labeled recovery tracers to the incubates, the steroids were extracted, separated by paper and thin-layer chromatography and crystallized to constant /sup 3/H//sup 14/C ratio in 3 consecutive crystals. The results showed that all tissues metabolized /sup 14/C testosterone into 4 major steroids: dihydrotestosterone (DHT), 5 alpha-androstane-3 alpha-17 beta diol (5 alpha-3 alpha-diol), delta 4-androstenedione and androsterone. The metabolites accounted for approximately 16% and approximately 6% of the conversion products in the immature and mature vas deferens respectively. There was no significant difference in /sup 14/C testosterone metabolism when VDP and VDD were compared within either age group of animals. However, the immature vas deferens was significantly more active compared to mature vas deferens in the synthesis of these metabolites, indicating that the activities of 5 alpha-reductase, 3 alpha-hydroxysteroid dehydrogenase and 17 beta-hydroxysteroid dehydrogenase diminish during sexual maturation. The possible physiological significance of these changes during maturation of the vas deferens is discussed.
- Research Organization:
- Department of Reproductive Medicine and Biology, University of Texas Medical School, Houston
- OSTI ID:
- 6710274
- Journal Information:
- Biol. Reprod.; (United States), Journal Name: Biol. Reprod.; (United States) Vol. 26:4; ISSN BIREB
- Country of Publication:
- United States
- Language:
- English
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59 BASIC BIOLOGICAL SCIENCES
ANDROGENS
ANDROSTANES
ANIMALS
BODY
CARBON 14 COMPOUNDS
CHEMICAL ANALYSIS
CHROMATOGRAPHY
COMPARATIVE EVALUATIONS
ENZYME ACTIVITY
GAMETES
GERM CELLS
GONADS
HORMONES
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KETONES
LABELLED COMPOUNDS
MALE GENITALS
MAMMALS
METABOLISM
METABOLITES
ORGANIC COMPOUNDS
ORGANS
PHYSIOLOGY
QUANTITATIVE CHEMICAL ANALYSIS
RATS
RODENTS
SEPARATION PROCESSES
SPERMATOZOA
STEROID HORMONES
STEROIDS
TESTES
TESTOSTERONE
THIN-LAYER CHROMATOGRAPHY
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES