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Human C-peptide

Part II: Clinical studies

Humanes C-Peptid

II. Klinische Studien

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Zusammenfassung

Humanes C-Peptid wird radioimmunologisch bestimmt. Bei der Gelfiltration von Serum einer gesunden Probandin und einer Patientin mit Inselzellcarcinom erscheint C-Peptid (MG 3025) vor Insulin (MG 5808). Die molaren Konzentrationen für C-Peptid sind viel höher als für Insulin. Humanes Proinsulin reagiert mit unserem Antiserum gegen synthetisches humanes C-Peptid kreuz.

Bei direkter Messung im Serum zeigen 25 Gesunde einen Nüchternspiegel für immunologisch meßbares C-Peptid (IMCP) von 1,8 (±0,4) ng/ml, entsprechend 60,4 × 10−11 Mol/l. Die molare Konzentration für immunologisch meßbares Insulin (IMI) beträgt ungefähr ein Fünftel dieses Wertes. Nach Stimulation der Beta-Zell-Sekretion mit i.v. Glukose oder Glukose-Glibenclamid finden sich bei Gesunden unterschiedliche Verl:aufe für IMCP und IMI. Wahrscheinlich erklärt sich dieser Befund mit einem unterschiedlichen peripheren Metabolismus beider Substanzen. Aus unseren Ergebnissen schließen wir, daß bei Messungen im peripheren venösen Serum C-Peptid ein besserer Indikator der Beta-Zell-Sekretion ist als Insulin.

Von 26 insulinpflichtigen juvenilen Diabetikern zeigen 15 nicht meßbare und 11 subnormale IMCP Spiegel im Nüchternserum. 1–2 h nach dem Frühstück findet sich kein Anstieg für IMCP. Bei 4 juvenilen Diabetikern, die während einer totalen Remissionsphase ohne Insulin auskommen, liegen die IMCP Nüchternkonzentrationen im Normbereich für Gesunde oder darüber. Nur bei 2 von 24 erwachsenen Diabetikern (16 Fälle mit Insulin behandelt, 8 mit Tabletten) sind die IMCP Nüchternkonzentrationen nicht meßbar, bei 4 weiteren Patienten liegen sie unter, in den restlichen 18 Fällen dagegen über 1 ng/ml Serum. Die Stimulierbarkeit der Beta-Zell-Sekretion durch Glukose-Glibenclamid ist bei allen erwachsenen Diabetikern im Vergleich mit Gesunden mehr oder weniger eingeschränkt.

Summary

Human C-peptide is determined by radioimmunoassay. On gel filtration of serum from a healthy subject and from a patient with islet cell carcinoma, C-peptide (MW 3025) appears ahead of insulin (MW 5808) and shows much higher molar concentrations than the hormone. Human proinsulin cross-reacts with our antiserum to synthetic human C-peptide.

On direct determination of immunomeasurable C-peptide (IMCP) in fasting serum of 25 healthy subjects we find an average of 1.8 (±0.4) ng/ml, corresponding to 60.4 × 10−11 Mol/l. The molar concentration is about five-fold as compared to IMI (immunomeasurable insulin).

IMCP and IMI patterns are not identical on stimulation of beta-cell secretion in healthy subjects by i.v. glucose or glucose-glibenclamide. This is probably due to differences in peripheral metabolism of both compounds. We conclude from our results that C-peptide determined in peripheral venous serum is a better indicator of beta-cell secretion than is insulin.

Among 26 insulin-treated juvenile diabetics 15 show not measurable and 11 subnormal IMCP levels in fasting serum. No rise in IMCP is found 1–2 h following breakfast. Four juvenile patients receiving no insulin in a phase of total diabetes remission have normal or raised fasting IMCP concentrations. Only 2 out of 24 adult diabetics (16 treated with insulin and 8 with tablets) show non-measurable fasting IMCP concentrations, in another 4 patients values are below and in the remaining 18 cases above 1 ng/ml serum.

Stimulation of beta-cell secretion through glucoseglibenclamide is more or less impaired in all adult diabetics compared to the healthy subjects.

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References

  1. Beischer, W., Heinze, E., Keller, L., Thum, Ch., Tamàs, Gy. Pfeiffer, E.F.: Suitability and importance of C-peptide for the assessment of pancreatic beta-cell function. Presented at the 10th Acta Endocrinologica Congress, Amsterdam 1975. Acta endocr. (Kbh.), Suppl.199, 112 (1975)

    Google Scholar 

  2. Beischer, W., Keller, L., Heinze, E., Raptis, S., Tamàs, Gy., Thum, Ch., Pfeiffer, E.F.: Nachweis von körpereigenen Insulinreserven beim insulinbehandelten Diabetiker mittels C-Peptid-Bestimmung. Presented at the XII. Kongreß der Süddeutschen Gesellschaft für Innere Medizin, Stuttgart 1975. Therapiewoche26, 1936 (1976)

    Google Scholar 

  3. Beischer, W., Keller, L., Maas, M., Schiefer, E., Pfeiffer, E.F.: Human C-peptide, part I: radioimmunoassay. Klin. Wschr.,54, 709 (1976)

    PubMed  Google Scholar 

  4. Beischer, W., Keller, L., Schürmeyer, E., Raptis, S., Thum, Ch., Pfeiffer, E. F.: Insulin, Proinsulin und C-Peptid im Serum bei Hypoglycaemia factitia. Presented at the 81. Tagung der deutschen Gesellschaft für Innere Medizin, Wiesbaden 1975. Verh. dtsch. Ges. inn. Med. 81. Band, J.F. Bergmann Verlag, München, 1493 (1975)

  5. Beischer, W., Melani, F., Keller, L., Pfeiffer, E.F.: Chromatographic heterogeneity of insulin extracted from insulomas. J. clin. Endocr.40, 393 (1975)

    PubMed  Google Scholar 

  6. Beischer, W., Raptis, S., Keller, L., Heinze, E., Schröder, K.E., Pfeiffer, E.F.: Characterization of the residual beta-cell function in diabetics by a new C-peptide radioimmunoassay. Presented at the 11th annual meeting of the European Association for the study of Diabetes, Munich 1975. Diabetologia11, 332 (1975)

    Google Scholar 

  7. Block, M.B., Mako, M.E., Steiner, D.F., Rubenstein, A.H.: Circulating C-peptide immunoreactivity. Studies in normals and diabetic patients. Diabetes21, 1013 (1972a)

    PubMed  Google Scholar 

  8. Block, M.B., Mako, M.E., Steiner, D.F., Rubenstein, A.H.: Diabetic Ketoacidosis: evidence for C-peptide and proinsulin secretion following recovery. J. clin. Endocr.35, 402 (1972b)

    PubMed  Google Scholar 

  9. Block, M.B., Pildes, R.S., Mossabhoy, N.A., Steiner, D.F., Rubenstein, A.H.: C-peptide immunoreactivity (CPR): a new method for studying infants of insulin-treated diabetic mothers. Pediatrics53, 923 (1974)

    PubMed  Google Scholar 

  10. Block, M.B., Rosenfield, R.L., Mako, M.E., Steiner, D.F., Rubenstein, A.H.: Sequential changes in beta-cell function in insulin-treated diabetic patients assessed by C-peptide immunoreactivity. New Engl. J. Med.288, 1144 (1973)

    PubMed  Google Scholar 

  11. Conard, V.: Mesure de l'assimilation du glucose. Base théorique et applications cliniques. Acta gastro-ent. belg.18, 803 (1955)

    Google Scholar 

  12. Couropmitree, Ch., Freinkel, N., Nagel, T.C., Horwitz, D.L., Metzger, B., Rubenstein, A.H., Hahnel, R.: Plasma C-peptide and diagnosis of factitious hyperinsulinism. Ann. Intern. Med.82, 201 (1975)

    PubMed  Google Scholar 

  13. Heding, L.G., Larsen, U.D., Markussen, J., Jørgensen, K.H., Hallund, O.: Radioimmunoassays for human, pork and ox C-peptides and related substances. Horm. Metab. Res., Suppl.5, 40 (1974)

    Google Scholar 

  14. Heding, L.G., Rasmussen, S.M.: Human C-peptide in normal and diabetic subjects. Diabetologia11, 201 (1975)

    PubMed  Google Scholar 

  15. Horwitz, D.L., Starr, J.I., Mako, M.E., Blackard, W.G., Rubenstein, A.H.: Proinsulin, insulin, and C-peptide concentrations in human portal and peripheral blood. J. clin. Invest.55, 1278 (1975)

    PubMed  Google Scholar 

  16. Horwitz, D.L., Starr, J.I., Rubenstein, A.H., Steiner, D.F.: Serum connecting peptide — an indicator of beta-cell secretory function. Diabet. Abstr.22 (suppl. 1), 298 (1973)

    Google Scholar 

  17. Kaneko, T., Oka, H., Munemura, M., Oda, T., Yamashita, K., Suzuki, S., Yanaihara, N., Hashimoto, T., Yanaihara, Ch.: Radioimmunoassay of human proinsulin C-peptide using synthetic human connecting peptide. Endocr. jap.21, 141 (1974)

    Google Scholar 

  18. Katz, A.I., Rubenstein, A.H.: Metabolism of proinsulin, insulin and C-peptide in the rat. J. clin. Invest.52, 1113 (1973)

    PubMed  Google Scholar 

  19. Markussen, J., Heding, L.G., Jørgensen, K.H., Sundby, F.: Proinsulin, insulin and C-peptide. Horm. Metab. Res., Suppl.3, 33 (1971)

    Google Scholar 

  20. Melani, F., Rubenstein, A.H., Oyer, P.E., Steiner, D.F.: Identification of proinsulin and C-peptide in human serum by a specific immunoassay. Proc. nat. Acad. Sci.67, 148 (1970)

    PubMed  Google Scholar 

  21. Melani, F., Ryan, W.G., Rubenstein, A.H., Steiner, D.F.: Proinsulin secretion by a pancreatic beta-cell adenoma. New Engl. J. Med.283, 713 (1970)

    PubMed  Google Scholar 

  22. Pfeiffer, E.F., Raptis, S.: Controlled extension of oral antidiabetic therapy on former insulin dependent diabetics by means of the combined i.v. glibenclamide-glucose-response-test. Diabetologia8, 41 (1972)

    PubMed  Google Scholar 

  23. Pfeiffer, E.F., Raptis, S., Schröder, K.E.: Einmalige intravenöse Glibenclamid-Glucose-Belastung als Vorhersagetest. Dtsch. med. Wschr.99, 1281 (1974)

    PubMed  Google Scholar 

  24. Rubenstein, A.H., Clark, J.L., Melani, F., Steiner, D.F.: Secretion of proinsulin C-peptide by pancreatic β-cell and its circulation in blood. Nature224, 697 (1969)

    Google Scholar 

  25. Sandler, R., Horwitz, D.L., Rubenstein, A.H., Kuzuya, H.: Hypoglycemia and endogenous hyperinsulinism complicating diabetes mellitus. Amer. J. Med.59, 730 (1975)

    PubMed  Google Scholar 

  26. Stoll, R.W., Touber, J.L., Menahan,, L.A., Williams, R.H.: Clearance of porcine insulin, proinsulin, and connecting peptide by the isolated rat liver. Proc. Soc. exp. Biol.133, 894 (1970)

    Google Scholar 

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Authors and Affiliations

  1. Department of Internal Medicine, Endocrinology and Metabolism, University of Ulm, Ulm, Germany

    W. Beischer, E. Heinze, L. Keller, S. Raptis, W. Kerner & E. F. Pfeiffer

Authors
  1. W. Beischer
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  2. E. Heinze
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  3. L. Keller
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  4. S. Raptis
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  5. W. Kerner
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  6. E. F. Pfeiffer
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Supported by the Deutsche Forschungsgemeinschaft, (SFB 87)

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Beischer, W., Heinze, E., Keller, L. et al. Human C-peptide. Klin Wochenschr 54, 717–725 (1976). https://doi.org/10.1007/BF01470463

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