Skip to main content
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1978 Dec;75(12):6134–6138. doi: 10.1073/pnas.75.12.6134

Pituitary somatotrophs contain [Met]enkephalin-like immunoreactivity.

E Weber, K H Voigt, R Martin
PMCID: PMC393133  PMID: 366611

Abstract

Serial sections from epoxy resin-embedded rat anterior pituitaries were sequentially immunostained for endorphin, [Met]enkephalin, and growth hormone, respectively. We found that [Met]enkephalin immunoreactivity was confined to the growth hormone producing cells. Corticotropin/endorphin cells in the anterior pituitary from both normal and adrenalectomized rats did not contain any [Met]enkephalin immunoreactivity. When anterior pituitary cells were maintained in monolayer culture for 10 days, [Met]enkephalin immunoreactivity was still located in the growth hormone-producing cells although the staining was weaker than in the somatotrophs in pituitary tissue fixed immediately after death of the animals. This suggested that somatotrophs synthesize [Met]enkephalin. However, this cannot be proved conclusively until biosynthesis experiments have been performed. The following conclusions were drawn from these findings. (i) Anterior pituitary [Met]enkephalin is not an extraction artifact derived from beta-endorphin with which it shares the NH2-terminal pentapeptide sequence. (ii) In the anterior pituitary, beta-endorphin is not the precursor to [Met]enkephalin. [Met]Enkephalin in somatotrophs may be of brain origin and in the somatotrophs may be bound to intracellllar receptors as has been shown for luteotropin releasing hormone in gonadotropic cells.

Full text

PDF
6134

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Austen B. M., Smyth D. G., Snell C. R. gamma endorphin, alpha endorphin and Met-enkephalin are formed extracellularly from lipotropin C fragment. Nature. 1977 Oct 13;269(5629):619–621. doi: 10.1038/269619a0. [DOI] [PubMed] [Google Scholar]
  2. Birdsall N. J., Hulme E. C. C fragment of lipotropin has a high affinity for brain opiate receptors. Nature. 1976 Apr 29;260(5554):793–795. doi: 10.1038/260793a0. [DOI] [PubMed] [Google Scholar]
  3. Bloom F., Battenberg E., Rossier J., Ling N., Guillemin R. Neurons containing beta-endorphin in rat brain exist separately from those containing enkephalin: immunocytochemical studies. Proc Natl Acad Sci U S A. 1978 Mar;75(3):1591–1595. doi: 10.1073/pnas.75.3.1591. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Brinkley B. R., Murphy P., Richardson L. C. Procedure for embedding in situ selected cells cultured in vitro. J Cell Biol. 1967 Oct;35(1):279–283. doi: 10.1083/jcb.35.1.279. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Chrétien M., Benjannet S., Dragon N., Seidah N. G., Lis M. Isolation of peptides with opiate activity from sheep and human pituitaries: relationship to beta-lipotropin. Biochem Biophys Res Commun. 1976 Sep 20;72(2):472–478. doi: 10.1016/s0006-291x(76)80066-6. [DOI] [PubMed] [Google Scholar]
  6. Erlandsen S. L., Parsons J. A., Burke J. P., Redick J. A., Van Orden D. E., Van Orden L. S. A modification of the unlabeled antibody enzyme method using heterologous antisera for the light microscopic and ultrastructural localization of insulin, glucagon and growth hormone. J Histochem Cytochem. 1975 Sep;23(9):666–677. doi: 10.1177/23.9.1176760. [DOI] [PubMed] [Google Scholar]
  7. Etzrodt H., Schleyer M., Pfeiffer E. F. Immunological relatedness of human and porcine growth hormones. Hoppe Seylers Z Physiol Chem. 1975 Feb;356(2):119–126. doi: 10.1515/bchm2.1975.356.1.119. [DOI] [PubMed] [Google Scholar]
  8. Giagnoni G., Sabol S. L., Nirenberg M. Synthesis of opiate peptides by a clonal pituitary tumor cell line. Proc Natl Acad Sci U S A. 1977 Jun;74(6):2259–2263. doi: 10.1073/pnas.74.6.2259. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Graham R. C., Jr, Karnovsky M. J. The early stages of absorption of injected horseradish peroxidase in the proximal tubules of mouse kidney: ultrastructural cytochemistry by a new technique. J Histochem Cytochem. 1966 Apr;14(4):291–302. doi: 10.1177/14.4.291. [DOI] [PubMed] [Google Scholar]
  10. Guillemin R., Vargo T., Rossier J., Minick S., Ling N., Rivier C., Vale W., Bloom F. beta-Endorphin and adrenocorticotropin are selected concomitantly by the pituitary gland. Science. 1977 Sep 30;197(4311):1367–1369. doi: 10.1126/science.197601. [DOI] [PubMed] [Google Scholar]
  11. Hong J. S., Yang H. Y., Fratta W., Costa E. Determination of methionine enkephalin in discrete regions of rat brain. Brain Res. 1977 Oct 7;134(2):383–386. doi: 10.1016/0006-8993(77)91084-8. [DOI] [PubMed] [Google Scholar]
  12. Hughes J., Smith T. W., Kosterlitz H. W., Fothergill L. A., Morgan B. A., Morris H. R. Identification of two related pentapeptides from the brain with potent opiate agonist activity. Nature. 1975 Dec 18;258(5536):577–580. doi: 10.1038/258577a0. [DOI] [PubMed] [Google Scholar]
  13. Kemper B., Habener J. F., Potts J. T., Jr, Rich A. Proparathyroid hormone: identification of a biosynthetic precursor to parathyroid hormone. Proc Natl Acad Sci U S A. 1972 Mar;69(3):643–647. doi: 10.1073/pnas.69.3.643. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Lang R. E., Hilwig I., Voigt K. H., Fehm H. L., Pfeiffer E. F. Growth in monolayer culture of rat pituitary cells which synthetize and release acth. Acta Endocrinol (Copenh) 1975 Jul;79(3):421–430. doi: 10.1530/acta.0.0790421. [DOI] [PubMed] [Google Scholar]
  15. Li C. H., Barnafi L., Chrétien M., Chung D. Isolation and amino-acid sequence of beta-LPH from sheep pituitary glands. Nature. 1965 Dec 11;208(5015):1093–1094. doi: 10.1038/2081093b0. [DOI] [PubMed] [Google Scholar]
  16. Li C. H., Chung D. Isolation and structure of an untriakontapeptide with opiate activity from camel pituitary glands. Proc Natl Acad Sci U S A. 1976 Apr;73(4):1145–1148. doi: 10.1073/pnas.73.4.1145. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Loh H. H., Tseng L. F., Wei E., Li C. H. beta-endorphin is a potent analgesic agent. Proc Natl Acad Sci U S A. 1976 Aug;73(8):2895–2898. doi: 10.1073/pnas.73.8.2895. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Loh H. H., Tseng L. F., Wei E., Li C. H. beta-endorphin is a potent analgesic agent. Proc Natl Acad Sci U S A. 1976 Aug;73(8):2895–2898. doi: 10.1073/pnas.73.8.2895. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. MAYOR H. D., HAMPTON J. C., ROSARIO B. A simple method for removing the resin from epoxy-embedded tissue. J Biophys Biochem Cytol. 1961 Apr;9:909–910. doi: 10.1083/jcb.9.4.909. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Mains R. E., Eipper B. A. Coordinate synthesis of corticotropins and endorphins by mouse pituitary tumor cells. J Biol Chem. 1978 Feb 10;253(3):651–655. [PubMed] [Google Scholar]
  21. Mains R. E., Eipper B. A., Ling N. Common precursor to corticotropins and endorphins. Proc Natl Acad Sci U S A. 1977 Jul;74(7):3014–3018. doi: 10.1073/pnas.74.7.3014. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Miller R. J., Chang K. J., Cooper B., Cuatrecasas P. Radioimmunoassay and characterization of enkephalins in rat tissues. J Biol Chem. 1978 Jan 25;253(2):531–538. [PubMed] [Google Scholar]
  23. Pacold S. T., Kirsteins L., Hojvat S., Lawrence A. M. Biologically active pituitary hormones in the rat brain amygdaloid nucleus. Science. 1978 Feb 17;199(4330):804–806. doi: 10.1126/science.203034. [DOI] [PubMed] [Google Scholar]
  24. Roberts J. L., Herbert E. Characterization of a common precursor to corticotropin and beta-lipotropin: cell-free synthesis of the precursor and identification of corticotropin peptides in the molecule. Proc Natl Acad Sci U S A. 1977 Nov;74(11):4826–4830. doi: 10.1073/pnas.74.11.4826. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Rossier J., Vargo T. M., Minick S., Ling N., Bloom F. E., Guillemin R. Regional dissociation of beta-endorphin and enkephalin contents in rat brain and pituitary. Proc Natl Acad Sci U S A. 1977 Nov;74(11):5162–5165. doi: 10.1073/pnas.74.11.5162. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Rubinstein M., Stein S., Udenfriend S. Isolation and characterization of the opioid peptides from rat pituitary: beta-endorphin. Proc Natl Acad Sci U S A. 1977 Nov;74(11):4969–4972. doi: 10.1073/pnas.74.11.4969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Schleyer M., Voigt K. H., Etzrodt H. Preparation of porcine growth hormone. Hoppe Seylers Z Physiol Chem. 1974 Oct;355(10):1291–1298. doi: 10.1515/bchm2.1974.355.2.1291. [DOI] [PubMed] [Google Scholar]
  28. Schleyer M., Voigt K. H. Preparation of highly purified human somatotropin (growth hormone). Hoppe Seylers Z Physiol Chem. 1977 Dec;358(12):1557–1564. doi: 10.1515/bchm2.1977.358.2.1557. [DOI] [PubMed] [Google Scholar]
  29. Simantov R., Childers S. R., Snyder S. H. Opioid peptides: differentiation by radioimmunoassay and radioreceptor assay. Brain Res. 1977 Oct 28;135(2):358–367. doi: 10.1016/0006-8993(77)91039-3. [DOI] [PubMed] [Google Scholar]
  30. Simantov R., Kuhar M. J., Uhl G. R., Snyder S. H. Opioid peptide enkephalin: immunohistochemical mapping in rat central nervous system. Proc Natl Acad Sci U S A. 1977 May;74(5):2167–2171. doi: 10.1073/pnas.74.5.2167. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Skowsky W. R., Fisher D. A. The use of thyroglobulin to induce antigenicity to small molecules. J Lab Clin Med. 1972 Jul;80(1):134–144. [PubMed] [Google Scholar]
  32. Steiner D. F., Cunningham D., Spigelman L., Aten B. Insulin biosynthesis: evidence for a precursor. Science. 1967 Aug 11;157(3789):697–700. doi: 10.1126/science.157.3789.697. [DOI] [PubMed] [Google Scholar]
  33. Sternberger L. A., Hardy P. H., Jr, Cuculis J. J., Meyer H. G. The unlabeled antibody enzyme method of immunohistochemistry: preparation and properties of soluble antigen-antibody complex (horseradish peroxidase-antihorseradish peroxidase) and its use in identification of spirochetes. J Histochem Cytochem. 1970 May;18(5):315–333. doi: 10.1177/18.5.315. [DOI] [PubMed] [Google Scholar]
  34. Sternberger L. A., Petrali J. P., Joseph S. A., Meyer H. G., Mills K. R. Specificity of the immunocytochemical luteinizing hormone-releasing hormone receptor reaction. Endocrinology. 1978 Jan;102(1):63–73. doi: 10.1210/endo-102-1-63. [DOI] [PubMed] [Google Scholar]
  35. Watson S. J., Barchas J. D., Li C. H. beta-Lipotropin: localization of cells and axons in rat brain by immunocytochemistry. Proc Natl Acad Sci U S A. 1977 Nov;74(11):5155–5158. doi: 10.1073/pnas.74.11.5155. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Weber E., Voigt K. H., Martin R. Concomitant storage of ACTH- and endorphin-like immunoreactivity in the secretory granules of anterior pituitary corticotrophs. Brain Res. 1978 Nov 24;157(2):385–390. doi: 10.1016/0006-8993(78)90047-1. [DOI] [PubMed] [Google Scholar]
  37. Yang H. Y., Hong J. S., Costa E. Regional distribution of LEU and MET enkephalin in rat brain. Neuropharmacology. 1977 Apr;16(4):303–307. doi: 10.1016/0028-3908(77)90112-5. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES