[3 beta-Hydroxysteroid-dehydrogenases of the testis and epididymis of the Peking duck (Anas platyrhynchos L.)].

This study is concerned with the histochemical activity of hydrosteroid dehydrogenases (HSD), glucose-6-phosphate dehydrogenase (G6PDH), and 6-phosphogluconate dehydrogenase (6PGDH) in testis and epididymis of 20 male Pekin ducks. Various 3 beta-HSD, the G6PDH, and the 6PGDH were localized in these organs. 3 beta-etiocholane was much quicker utilized by the 3 beta-HSD than epiandrosterone, dehydroepiandrosterone, and androstendiol. The capability of testis Leydig cells of utilizing the 3 beta-etiocholane was higher in winter than in summer. The G6PDH and the 6PGDH in the Leydig cells and basal cell layer of the tubuli seminiferi contorti were active throughout the year. There was weak 3 beta-HSD activity in the epithelia of the ductuli efferentes distales and in the ductus epididymidis from March to June. The G6PDH and the 6PGDH showed positive reaction in the rete testis and ductuli efferentes proximales throughout the year. The 3 beta-HSD activity in testis and epididymis is saisonally different: In summer, there is no 3 beta-HSD activity in both organs. In winter, the 3 beta-HSD is demonstrable in the testis but not in the epididymis. In spring, there is 3 beta-HSD activity in the epididymis but not in the testis.