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. 1992 Jul 1;89(13):5759–5763. doi: 10.1073/pnas.89.13.5759

Evaluation of luteinizing hormone-releasing hormone antagonistic activity in vitro.

V J Csernus 1, A V Schally 1
PMCID: PMC402097  PMID: 1631057

Abstract

Antagonistic analogues of luteinizing hormone-releasing hormone (LHRH) belong to a class of compounds that can be utilized for treatment of some hormone-dependent cancers and gynecologic disorders. Recently, we synthesized and tested a large number of LHRH analogues for LHRH antagonistic activity in the dispersed pituitary cell superfusion system. This fast, reliable, and dynamic system made it possible for us not only to evaluate the relative amounts of an analogue required for suppression of the LH-releasing activity of exogenous LHRH but also provided quantitative data on dynamic interactions between the LHRH analogue, LHRH receptors, and LH secretion. Three experimental paradigms were used: (i) LHRH responses after preincubation with the antagonist, (ii) pulsatile, simultaneous infusion of LHRH and the antagonistic analogue, and (iii) effects of the analogues on ongoing, continuous LH secretion induced by prolonged stimulation with LHRH. From the data obtained, we conclude that (i) the suppression of the LHRH-induced LH release was more effective and longer lasting when the cells were preincubated with the antagonistic analogues before the LHRH stimulation than in the case of simultaneous exposure; (ii) not only the potency but also the time of onset and the duration of the LH release-suppressing activity varied according to the different peptides used, resulting in different shapes of response curves; and (iii) from the accurate data obtained in this dynamic system, quantitative parameters of the in vivo interactions between the antagonists and LHRH on the LHRH receptor can be calculated.

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Selected References

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  1. Badger T. M., Loughlin J. S., Naddaff P. G. The luteinizing hormone-releasing hormone (LHRH)-desensitized rat pituitary: luteinizing hormone responsiveness to LHRH in vitro. Endocrinology. 1983 Mar;112(3):793–799. doi: 10.1210/endo-112-3-793. [DOI] [PubMed] [Google Scholar]
  2. Baird C. J., Tharandt L., Tamarkin L. Regulation of luteinizing hormone release by pulsatile and continuous administration of gonadotropin-releasing hormone to superfused rat and hamster pituitary cells. Endocrinology. 1984 Mar;114(3):1041–1047. doi: 10.1210/endo-114-3-1041. [DOI] [PubMed] [Google Scholar]
  3. Bajusz S., Csernus V. J., Janaky T., Bokser L., Fekete M., Schally A. V. New antagonists of LHRH. II. Inhibition and potentiation of LHRH by closely related analogues. Int J Pept Protein Res. 1988 Dec;32(6):425–435. doi: 10.1111/j.1399-3011.1988.tb01373.x. [DOI] [PubMed] [Google Scholar]
  4. Bajusz S., Kovacs M., Gazdag M., Bokser L., Karashima T., Csernus V. J., Janaky T., Guoth J., Schally A. V. Highly potent antagonists of luteinizing hormone-releasing hormone free of edematogenic effects. Proc Natl Acad Sci U S A. 1988 Mar;85(5):1637–1641. doi: 10.1073/pnas.85.5.1637. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Conn P. M. The molecular basis of gonadotropin-releasing hormone action. Endocr Rev. 1986 Feb;7(1):3–10. doi: 10.1210/edrv-7-1-3. [DOI] [PubMed] [Google Scholar]
  6. Csernus V. J., Szende B., Groot K., Redding T. W., Schally A. V. Development of radioimmunoassay for a potent luteinizing hormone-releasing hormone antagonist. Evaluation of serum levels after injection of [Ac-3-(2-naphthyl)-D-Ala1, D-Phe(pCl)2, 3-(3-pyridyl)-D-Ala3, D-Cit6, D-Ala10] LHRH. Arzneimittelforschung. 1990 Feb;40(2 Pt 1):111–118. [PubMed] [Google Scholar]
  7. Csernus V. J., Szende B., Schally A. V. Release of peptides from sustained delivery systems (microcapsules and microparticles) in vivo. A histological and immunohistochemical study. Int J Pept Protein Res. 1990 Jun;35(6):557–565. doi: 10.1111/j.1399-3011.1990.tb00262.x. [DOI] [PubMed] [Google Scholar]
  8. Fekete M., Bajusz S., Groot K., Csernus V. J., Schally A. V. Comparison of different agonists and antagonists of luteinizing hormone-releasing hormone for receptor-binding ability to rat pituitary and human breast cancer membranes. Endocrinology. 1989 Feb;124(2):946–955. doi: 10.1210/endo-124-2-946. [DOI] [PubMed] [Google Scholar]
  9. Heber D., Dodson R., Swerdloff R. S., Channabasavaiah K., Stewart J. M. Pituitary receptor site blockade by a gonadotropin-releasing hormone antagonist in vivo: mechanism of action. Science. 1982 Apr 23;216(4544):420–421. doi: 10.1126/science.6280278. [DOI] [PubMed] [Google Scholar]
  10. Karten M. J., Rivier J. E. Gonadotropin-releasing hormone analog design. Structure-function studies toward the development of agonists and antagonists: rationale and perspective. Endocr Rev. 1986 Feb;7(1):44–66. doi: 10.1210/edrv-7-1-44. [DOI] [PubMed] [Google Scholar]
  11. Korkut E., Bokser L., Comaru-Schally A. M., Groot K., Schally A. V. Inhibition of growth of experimental prostate cancer with sustained delivery systems (microcapsules and microgranules) of the luteinizing hormone-releasing hormone antagonist SB-75. Proc Natl Acad Sci U S A. 1991 Feb 1;88(3):844–848. doi: 10.1073/pnas.88.3.844. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Loumaye E., Wynn P. C., Coy D., Catt K. J. Receptor-binding properties of gonadotropin-releasing hormone derivatives. Prolonged receptor occupancy and cell-surface localization of a potent antagonist analog. J Biol Chem. 1984 Oct 25;259(20):12663–12671. [PubMed] [Google Scholar]
  13. Naor Z., Katikineni M., Loumaye E., Vela A. G., Dufau M. L., Catt K. J. Compartmentalization of luteinizing hormone pools: dynamics of gonadotropin releasing hormone action in superfused pituitary cells. Mol Cell Endocrinol. 1982 Jul;27(2):213–220. doi: 10.1016/0303-7207(82)90110-1. [DOI] [PubMed] [Google Scholar]
  14. SAFFRAN M., SCHALLY A. V. The release of corticotrophin by anterior pituitary tissue in vitro. Can J Biochem Physiol. 1955 May;33(3):408–415. [PubMed] [Google Scholar]
  15. Schally A. V., Comaru-Schally A. M., Redding T. W. Antitumor effects of analogs of hypothalamic hormones in endocrine-dependent cancers. Proc Soc Exp Biol Med. 1984 Mar;175(3):259–281. doi: 10.3181/00379727-175-41797. [DOI] [PubMed] [Google Scholar]
  16. Schally A. V., Coy D. H., Meyers C. A. Hypothalamic regulatory hormones. Annu Rev Biochem. 1978;47:89–128. doi: 10.1146/annurev.bi.47.070178.000513. [DOI] [PubMed] [Google Scholar]
  17. Smith M. A., Vale W. W. Desensitization to gonadotropin-releasing hormone observed in superfused pituitary cells on Cytodex beads. Endocrinology. 1981 Mar;108(3):752–759. doi: 10.1210/endo-108-3-752. [DOI] [PubMed] [Google Scholar]
  18. Srkalovic G., Bokser L., Radulovic S., Korkut E., Schally A. V. Receptors for luteinizing hormone-releasing hormone (LHRH) in Dunning R3327 prostate cancers and rat anterior pituitaries after treatment with a sustained delivery system of LHRH antagonist SB-75. Endocrinology. 1990 Dec;127(6):3052–3060. doi: 10.1210/endo-127-6-3052. [DOI] [PubMed] [Google Scholar]
  19. Szende B., Srkalovic G., Groot K., Lapis K., Schally A. V. Growth inhibition of mouse MXT mammary tumor by the luteinizing hormone-releasing hormone antagonist SB-75. J Natl Cancer Inst. 1990 Mar 21;82(6):513–517. doi: 10.1093/jnci/82.6.513. [DOI] [PubMed] [Google Scholar]
  20. Szende B., Srkalovic G., Groot K., Lapis K., Schally A. V. Regression of nitrosamine-induced pancreatic cancers in hamsters treated with luteinizing hormone-releasing hormone antagonists or agonists. Cancer Res. 1990 Jun 15;50(12):3716–3721. [PubMed] [Google Scholar]
  21. Vickery B. H. Comparison of the potential for therapeutic utilities with gonadotropin-releasing hormone agonists and antagonists. Endocr Rev. 1986 Feb;7(1):115–124. doi: 10.1210/edrv-7-1-115. [DOI] [PubMed] [Google Scholar]
  22. Yeo T., Grossman A., Belchetz P., Besser G. M. Response of luteinizing hormone from columns of dispersed rat pituitary cells to a highly potent analogue of luteinizing hormone releasing hormone. J Endocrinol. 1981 Oct;91(1):33–41. doi: 10.1677/joe.0.0910033. [DOI] [PubMed] [Google Scholar]

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