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Computer Analysis of the Binding Reaction between hCG and Gonadotropin Receptors of the Rat Testis

  • J. M. Ketelslegers
  • G. D. Knott
  • K. J. Catt
Part of the Current Topics in Molecular Endocrinology book series (CTME, volume 1)

Abstract

The presence of specific high-affinity binding sites for luteinizng hormone (LH) and human chorionic gonadotropin (hCG) has been established in the Leydig cells of the rat testis (1–3). The binding of hCG to these receptors has been demonstrated to be a saturable process, and the velocity of binding shows marked temperature dependence (3). Analysis of gonadotropin binding data by Scatchard plots previously indicated the presence of a single class of binding sites (3). To define more accurately the association constant and the rate constants of this hormone-receptor interaction, more detailed equilibrium and kinetic experiments were performed, and the data analyzed with an interactive non-linear curve fitting program. This analytical system (MLAB) has been previously described (4, 5), and runs on a PDP-10 digital time-sharing computer. This approach has the advantage of permitting the use of complex models while performing simultaneous fits to multiple sets of data, without a significant increase in the complexity of the computation procedure. In particular, data expressing the total bound hormone and the non-specifically bound hormone as functions of the initial hormone concentration could be analyzed simultaneously, with computation of specific binding from the results of the simultaneous fitting process.

Keywords

Hormone Concentration Dissociation Experiment Association Rate Constant Gonadotropin Receptor Bovine Corpus Luteum 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    DeKretser, D. M., Catt, K.J., Burger, H. G. and Smith, G. C., J. Endocr. 43: 105, 1969.CrossRefGoogle Scholar
  2. 2.
    Catt, K. J., Dufau, M. L. and Tsuruhara, T., J. Clin. Endocr. 32: 860, 1971.PubMedCrossRefGoogle Scholar
  3. 3.
    Catt, K. J., Tsuruhara, T., and Dufau, M. L., Biochim. Biophys. Acta 279: 194, 1972.PubMedCrossRefGoogle Scholar
  4. 4.
    Knott, G. D. and Reece, D. K., in Proceedings of the ONLINE ‘72 International Conference, Vol. 1, pp. 497–526, Brunel University, England, Sept. 1972.Google Scholar
  5. 5.
    Knott, G. D. and Shrager, R. I., In Computer Graphics: Proceedings of the SIGGRAPH Computers in Medicine Symposium, Vol. 6, No. 4, pp. 138–141, ACM, SIGGRAPH Notices, Winter 1972.CrossRefGoogle Scholar
  6. 6.
    MacArthur, J. W., Endocrinology 50: 304, 1952.CrossRefGoogle Scholar
  7. 7.
    Dufau, M. L., Catt, K. J., and Tsuruhara, T., Biochim. Biophys. Acta 252: 574, 1971.PubMedCrossRefGoogle Scholar
  8. 8.
    Catt, K. J., Dufau, M. L., and Tsuruhara, T., J. Clin. Endocr. 34: 123, 1972.PubMedCrossRefGoogle Scholar
  9. 9.
    Bellisario, R., Carlsen, R. B. and Bahl, O. P., J. Biol. Chem. 248: 6796, 1973.PubMedGoogle Scholar
  10. 10.
    Carlsen, R. B., Bahl, O. P., and Swaminathan, N., J. Biol. Chem. 248: 6810, 1973.PubMedGoogle Scholar
  11. 11.
    Catt, K. J., Acta Endocrinol. (Kbh) 63, Suppl. 142: 222, 1969.Google Scholar
  12. 12.
    Dufau, M. L., Catt, K. J., and Tsuruhara, T., Proc. Natl. Acad. Sci. USA, 69: 2414, 1972.PubMedCrossRefGoogle Scholar
  13. 13.
    Scatchard, G., Ann. N. Y. Acad. Sci. 51: 660, 1949.CrossRefGoogle Scholar
  14. 14.
    Gospodarowicz, D., J. Biol. Chem. 248: 5042, 1973.PubMedGoogle Scholar
  15. 15.
    Lee, C. Y., and Ryan, R. J., Biochemistry 12: 4609, 1973.PubMedCrossRefGoogle Scholar
  16. 16.
    Tsuruhara, T., Van Hall, E. V., Dufau, M. L., and Catt, K. J., Endocrinology 91: 463, 1972.PubMedCrossRefGoogle Scholar
  17. 17.
    Dufau, M. L., Charreau, E. H., Ryan, D., and Catt, K. J., F.E. B. S. Letters 39: 149, 1974.CrossRefGoogle Scholar
  18. 18.
    Midgley, A. R., In International Congress on Gonadotropins, Bangalore, India, 1973 (in press).Google Scholar
  19. 19.
    Ketelslegers, J. M., Knott, G., and Catt, K. J., unpublished observations.Google Scholar

Copyright information

© Plenum Press, New York 1974

Authors and Affiliations

  • J. M. Ketelslegers
    • 1
    • 2
  • G. D. Knott
    • 1
    • 2
  • K. J. Catt
    • 1
    • 2
  1. 1.Section on Hormonal RegulationNational Institute of Child Health and Human DevelopmenUSA
  2. 2.Division of Computer ResearchNational Institutes of HealthBethesdaUSA

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