Research in Experimental Medicine

, Volume 172, Issue 3, pp 239–246 | Cite as

Augmentation ofin vitro pituitary biotransformation of testosterone due to orchidectomy and its relation to serum gonadotropins in the rat

  • D. Gupta
  • W. Klemm
  • M. Eichner
Article

Summary

The biotransformation of testosterone to its metabolites by the anterior pituitary gland and the relation between the products formed and the circulating levels of LH and FSH were examined in male rats at various stages of sexual maturation. The animals were either intact controls or castrated 4 and 7 days prior to the investigation. Castration greatly increased testosterone biotransformation to its 5α-reduced products, but did not affect the formation of androstendione. It was concluded that castration and the eventual rise of LH-RH stimulated the 5α-reductase activity but not the 17β-ol-dehydrogenase system. This is reflected in the significant relationship between the circulating gonadotropins and 5α-metabolites of testosterone but not androstendione.

Key words

Pituitary biotransformation Testosterone metabolites Serum LH FSH Orchidectomy Maturation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Massa, R., Stupnicka, E., Kniewald, Z., Martini, L.: The transformation of testosterone into DHT by the brain and the anterior pituitary. J. Steroid. Biochem.3, 385–399 (1972)PubMedGoogle Scholar
  2. 2.
    Denef, C., Magnus, C., McEwen, B. S.: Sex differences and hormonal control of testosterone metabolism in rat-pituitary and brain. J. Endocr.59, 605–621 (1973)PubMedGoogle Scholar
  3. 3.
    Klemm, W., Gupta, D.: Pituitary biotransformation of testosterone to its 5α-reduced metabolites in sexually maturing male rats and following orchidectomy and experimental bilateral cryptorchidism. J. Endocr.65, 12 P (1975)Google Scholar
  4. 4.
    Sholiton, L. J., Jones, C. E., Werk, E. E.: The uptake and metabolism of (1,2-3H)-testosterone by the brain of functionally hepatectomized and totally eviscerated male rats. Steroids20, 399–415 (1972)PubMedGoogle Scholar
  5. 5.
    Sholl, S. A., Robinson, J. A., Goy, R. W.: Neural uptake and metabolism of testosterone and dihydrotestosterone in the guinea pig. Steroids25, 203–215 (1975)PubMedGoogle Scholar
  6. 6.
    Denef, C., Magnus, C., McEwen, B. S.: Sex-dependent changes in pituitary 5α-dihydrotestosterone and 3α-androstanediol formation during postnatal development and puberty in the rat. Endocrinology94, 1265–1274 (1974)PubMedGoogle Scholar
  7. 7.
    Bruchowsky, N., Wilson, J. D.: The conversion of testosterone to 5α-androstan-17β-ol-3-one by rat prostate in vivo and in vitro. J. Biol. Chem.243, 2012–2021 (1968)PubMedGoogle Scholar
  8. 8.
    Kingsley, T. R., Bogdanove, E. M.: Direct feedback of androgens: localized effects of intrapituitary implants of androgens on gonadotrophic cells and hormone stores. Endrocrinology93, 1398–1409 (1975)Google Scholar
  9. 9.
    Gupta, D., Rager, K., Zarzycki, J., Eichner, M.: Levels of luteinizing hormone, folliclestimulating hormone, testosterone and dihydrotestosterone in rats and after orchidectomy and experimental bilateral cryptorchidism. J. Endocr.66, 183–193 (1975)PubMedGoogle Scholar
  10. 10.
    Greenwood, F. C., Hunter, W. M., Glover, J. S.: The preparation of I-131 labelled human growth hormone of high specific radioactivity. Biochem. J.89, 114–123 (1963)PubMedGoogle Scholar
  11. 11.
    Swerdloff, R. S., Walsh, P. C., Jacobs, H. S., Odell, W. D.: Serum LH and FSH during sexual maturation in the male rat: effect of castration and cryptorchidism. Endocrinology88, 120–128 (1971)PubMedGoogle Scholar
  12. 12.
    Root, A. W., Russ, R. D.: Short-term effect of castration upon pituitary and serum levels of luteinizing hormone and follicle stimulating hormone in male rats. Acta Endocrinol. (Kbh.)70, 665–675 (1972)Google Scholar
  13. 13.
    Yamamoto, M., Diebel, N. D., Bogdanove, E. H.: Analysis of initial and delayed effects of orchidectomy and ovariectomy on pituitary and serum LH levels in adults and immature rats. Endocrinology86, 1102–1111 (1970)PubMedGoogle Scholar
  14. 14.
    Amatayakul, E., Ryan, R. T., Uozumi, T., Albert, A.: A reinvestigation of testicular-anterior pituitary relationship in the rat: I. Effect of castration and cryptorchidism. Endocrinology88, 872–880 (1971)PubMedGoogle Scholar
  15. 15.
    Gupta, D.: Gonadal steroids and gonadotrophin feedback regulation of mammalian sexual maturation. In Recent Progress in Reproductive Endocrinology, pp. 543–564. Eds. P. G. Crosignani, V. H. T. James. London: Academic Press 1974Google Scholar
  16. 16.
    Debeljuk, L., Arimura, A., Schally, A. V.: Studies on the pituitary responsiveness to luteinizing hormone-releasing hormone (LH-RH) in intact male rats of different ages. Endocrinology90, 585–588 (1972)PubMedGoogle Scholar

Copyright information

© Springer-Verlag 1978

Authors and Affiliations

  • D. Gupta
    • 1
  • W. Klemm
    • 1
  • M. Eichner
    • 1
  1. 1.Department of Diagnostic EndocrinologyUniversity Children's Hospital, University of TübingenTübingenFederal Republic of Germany

Personalised recommendations