title: The involvement of androgens in the control of epididymal protein synthesis and amino acid transport in the rat.
abstract: The effect of androgen withdrawal upon different parameters of the rat epididymis has been investigated, as well as the early response of these to the readministration of testosterone. The weight, protein and RNA content of the epididymides decreased after castration. However, their response to a single injection of 6 mg testosterone propionate in oil administered 24 hr before sacrifice, varied according to the parameter examined. Epididymal weight increased after androgen was given to rats castrated for 3 days or less. The protein content was moderately elevated when testosterone was administered to rats castrated for 3, 6 or 13 days. The RNA content increased sharply after androgen, the magnitude of the response being proportional to the duration of castration. These changes in epididymal trophism were dramatically illustrated by the 50% decrease in amino acid incorporation into acid insoluble material already measurable 24 hr after castration. This effect was reverted by testosterone propionate administered 24 hr before sacrifice. The free alcohol form of testosterone given at the same dose induced a significant increase in this parameter as early as 12 hr after its intraperitoneal injection. Finally, we could demonstrate the existence of active transport of amino acids into the epididymal cells and the stimulatory effect of testosterone upon this function.
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D002369:Castration; D004247:DNA / Q000096:biosynthesis; D004822:Epididymis / Q000378:metabolism*; D008297:Male; D009929:Organ Size; D014176:Protein Biosynthesis; D012313:RNA / Q000096:biosynthesis; D051381:Rats; D013268:Stimulation, Chemical; D013739:Testosterone / Q000502:physiology*
chemical_list: D000596:Amino Acids; D013739:Testosterone; D012313:RNA; D004247:DNA