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Orchidectomy Induces Temporal and Regional Changes in the Synthesis and Processing of the LHRH Prohormone in the Rat Brain

  • M. C. Culler
  • W. C. Wetsel
  • M. M. Valenca
  • C. A. Johnston
  • C. Masotto
  • M. Sar
  • A. Negro-Vilar
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 219)

Abstract

Recently, the sequence of the cDNA which encodes the LHRH-prohormone was elucidated from human placenta and human and rat hypothalamus and the corresponding amino acid sequence deduced (Seeburg et al., 1984 and Adelman et al., 1986). In addition to LHRH, the prohormone contains a 56 amino acid sequence, designated gonadotropin-releasing hormone associated peptide (GAP), which is attached to the C-terminus of the LHRH decapep-tide. Although not yet confirmed, the human GAP sequence has been reported to possess both gonadotropin-releasing and prolactin inhibiting activity (Nikolics et al., 1985). Additionally, a 13-amino acid fragment of the human GAP sequence (proLHRH 14–26) has been reported to stimulate gonadotropin release (Millar et al., 1986). Regardless of whether the non-LHRH portion of the LHRH prohormone contains biological activity, this sequence can serve as a valuable marker for studies of LHRH prohormone synthesis, processing and degradation. In order to initiate these types of studies, we have generated specific antisera (MC-1, 2 and 3) against a fragment of the human GAP sequence (proLHRH 38–66) and developed a radioimmunoassay procedure for the quantitation of GAP (Culler and Negro-Vilar, 1986). The antisera are specific for midportion sequences of the GAP molecule and do not cross-react with any other known brain peptide.

Keywords

Median Eminence Immunocytochemical Localization Ratio Shift Human Luteinizing Hormone Radioimmunoassay Procedure 
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. Adelman JP, Mason AJ, Hayflick JS, Seeburg PH, 1986. Isolation of the gene and hypothalamic cDNA for the common precursor of gonadotropin-releasing hormone and prolactin release-inhibiting factor in human and rat. Proc Natl Acad Sci USA 83:179–183PubMedCrossRefGoogle Scholar
  2. Culler MD, Negro-Vilar A, 1986. Development of specific antisera and a radioimmunoassay procedure for the gonadotropin-releasing hormone associated peptide (GAP) of the LHRH prohormone. Brain Res Bull 17:219–223PubMedCrossRefGoogle Scholar
  3. Hedger MP, Robertson DM, Browne CA, deKretser DM, 1985. The isolation and measurement of luteinizing hormone-releasing hormone (LHRH) from the rat testis. Mol Cell Endocrinol 42:24–29CrossRefGoogle Scholar
  4. Mason AJ, Hayflick JS, Zoeller RT, Young WS, Phillips HS, Nikolics K, Seeburg PH, 1986a. A deletion truncating the gonadotropin releasing hormone gene is responsible for hypogonadism in the hpg mouse. Science 234:1366–1371PubMedCrossRefGoogle Scholar
  5. Mason AJ, Pitts SL, Nikolics K, Szonyi E, Wilcox JN, Seeburg PH, Stewart TA, 1986b. The hypogonadal mouse: reproductive functions restored by gene therapy. Science 234:1372–1378PubMedCrossRefGoogle Scholar
  6. Millar RP, Wormald PJ, Milton RC de L, 1986. Stimulation of gonadotropin release by a non-GnRH peptide sequence of the GnRH precursor. Science 232:68–70PubMedCrossRefGoogle Scholar
  7. Nikolics K, Mason AJ, Szonyi E, Ramachandran J, Seeburg PH, 1985. A prolactin-inhibiting factor within the precursor for human gonadotropin-releasing hormone. Nature 316:511–517PubMedCrossRefGoogle Scholar
  8. Phillips HS, Nikolics K, Branton D, Seeburg PH, 1985. Immunocytochemical localization in rat brain of a prolactin release-inhibiting sequence of gonadotropin-releasing hormone prohormone. Nature 316:542–545PubMedCrossRefGoogle Scholar
  9. Sar M, Culler MD, McGimsey WC, Negro-Vilar A, 1987. Immunocytochemical localization of the gonadotropin-releasing hormone associated peptide of the LHRH-precursor. Neuroendocrinology 45:172–175PubMedCrossRefGoogle Scholar
  10. Seeburg PH, Adelman JP, 1984. Characterization of cDNA for precursor of human luteinizing hormone releasing hormone. Nature 311:666–668PubMedCrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • M. C. Culler
    • 1
  • W. C. Wetsel
    • 1
  • M. M. Valenca
    • 1
  • C. A. Johnston
    • 1
  • C. Masotto
    • 1
  • M. Sar
    • 2
  • A. Negro-Vilar
    • 1
  1. 1.Reproductive Neuroendocrinology Section, LRDT, National Institute of Environmental Health SciencesNIHUSA
  2. 2.Department of AnatomyUniversity of North CarolinaChapel HillUSA

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