International Journal of Pancreatology

, Volume 3, Issue 5, pp 357–366 | Cite as

To extract or not to extract in secretin radioimmunoassay?

  • Michael Fried
  • Cornelia Schulthess
  • Christoph Beglinger
  • Brigitte Müller
  • Klaus Gyr
Reseach Papers


The importance of an ethanol extraction procedure in the radioimmunoassay of plasma secretin was investigated. The extraction step led to a higher assay sensitivity of 0.35 fmol/ml, compared to 5.93 fmol/ml using unextracted samples. The rise of plasma secretin after infusion of a low dose of secretin (1 pmol·kg−1·h−1) in 10 healthy humans was only detected after sample extraction. Higher doses (3 and 9 pmol·kg−1·h−1) resulted in increments of plasma IRS (immunoreactive secretin), which could be recorded both with and without sample extraction. After a steak meal 7 of 10 subjects showed a significant increase of plasma secretin assaying extracted plasma samples. The secretin release occurred in spikes. The mean increase of plasma IRS in this group was 0.6 fmol/ml, the mean maximal secretin release above basal was 2.3 fmol/ml. Without sample extraction, plasma secretin was not significantly changed. We conclude that plasma samples should be extracted in order to detect physiological postprandial secretin release.

Key words

Secretion radioimmunoassay Ethanol extraction humans 


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  1. 1.
    Tai HH, Chey WY. Rapid extraction of secretin from plasma by XAD-2 resin and its application in the radioimmunoassay of secretin. Analyt Biochem 1978;87:376–385.PubMedCrossRefGoogle Scholar
  2. 2.
    Schaffalitzky de Muckadell OB, Fahrenkrug J. Radioimmunoassay of secretin in plasma. Scand J Clin Lab Invest 1977;37:155–162.PubMedGoogle Scholar
  3. 3.
    Gyr K, Beglinger C, Fried M, Grötzinger U, Kayasseh L, Stalder GA, Girard J. Plasma secretin and pancreatic response to various stimulants including a meal. Am J Physiol 1984;246: G535-G542.PubMedGoogle Scholar
  4. 4.
    Hanssen LE, Torjesen P. Radioimmunoassay of secretin in human plasma. Scand J Gastroent 1977;12:481–488.PubMedGoogle Scholar
  5. 5.
    Kleibeuker JH, Eysselein VE, Maxwell VE, Walsh JH. Role of endogenous secretin in acid-induced inhibition of human gastric function. J Clin Invest 1984;73:526–532.PubMedCrossRefGoogle Scholar
  6. 6.
    Yang R-K, Li H-R, Eng J, Greenstein R, Straus E, Yalow RS. Secretin responses to feeding and acid load. J Lab Clin Med 1983;102:17–23.PubMedGoogle Scholar
  7. 7.
    Burhol PG, Waldum HL. Radioimmunoassay of secretin in acidified plasma. Acta Hepato-Gastroenterol 1978;25:474–481.Google Scholar
  8. 8.
    Byrnes DJ, Marjason JP. Radioimmunoassay of secretin in plasma. Horm Metab Res 1976;8:361–365.PubMedGoogle Scholar
  9. 9.
    Häcki WH, Bloom SR, Mitznegg P, Domschke W, Domschke S, Belohlavek D, Demling L, Wünsch E. Plasma secretin and pancreatic bicarbonate response to exogenous secretin in man. Gut 1977;18:191–195.PubMedCrossRefGoogle Scholar
  10. 10.
    Miller TA, Konturek SJ, Llanos OO, Rayford PL, Thompson JC. The effect of fat on secretin release. Ann Surg 1983;187:303–308.CrossRefGoogle Scholar
  11. 11.
    Pelletier MJ, Chayvialle JAP, Minaire Y, Uneven and transient secretin release after a liquid test meal. Gastroenterology 1978;75:1124–1132.PubMedGoogle Scholar
  12. 12.
    Chang TM, Chey WY. Radioimmunoassay of secretin. Dig Dis Sci 1980;25:529–552.PubMedCrossRefGoogle Scholar
  13. 13.
    You CH, Rominger JM, Chey WY. Effects of atropine on the action and release of secretin in humans. Am J Physiol 1982;242:G608-G611.PubMedGoogle Scholar
  14. 14.
    Schaffalitzky de Muckadell OB, Fahrenkrug J, Watt-Boolsen S, Worning H. Pancreatic response and plasma secretin concentration during infusion of low dose secretin in man. Scand J Gastroent 1978;13:305–311.PubMedCrossRefGoogle Scholar
  15. 15.
    Fahrenkrug J, Schaffalitzky de Muckadell OB. Plasma secretin concentration in man: Effect of intraduodenal glucose, fat, amino acids, ethanol, HCL or ingestion of a meal. Eur J Clin Invest 1977;7:201–203.PubMedCrossRefGoogle Scholar
  16. 16.
    Lee KY, Tai HH, Chey WY. Plasma secretin and gastrin responses to a meat meal and duodenal acidification in dogs. Am J Physiol 1976;230:784–788.PubMedGoogle Scholar
  17. 17.
    Burhol PG, Waldum HL, Jorde R, Lygren I. The effect of a test meal on plasma vasoactive intestinal polypeptide (VIP), gastric inhibitory polypeptide (GIP), and secretin in man. Scand J Gastroent 1979;14:939–943.PubMedGoogle Scholar
  18. 18.
    Kolts BE, McGuigan JM, Radioimmunoassay measurement of secretin half-life in man. Gastroenterology 1977;72:55–60.PubMedGoogle Scholar
  19. 19.
    Beglinger C, Fried M, Whitehouse I, Jansen JB, Lamers CB, Gyr K. Pancreatic enzyme response to a liquid meal and to hormonal stimulation. J Clin Invest 1985;75:1471–1476.PubMedCrossRefGoogle Scholar
  20. 20.
    Schaffalitzky de Muckadell OB, Fahrenkrug J. Secretion pattern of secretin in man: regulation by gastric acid. Gut 1978;19:812–818.PubMedCrossRefGoogle Scholar

Copyright information

© Elsevier Science Publishers B.V. (Biomedical Division) 1988

Authors and Affiliations

  • Michael Fried
    • 1
  • Cornelia Schulthess
    • 1
  • Christoph Beglinger
    • 1
  • Brigitte Müller
    • 1
  • Klaus Gyr
    • 1
  1. 1.Division of Gastroenterology, Outpatient Clinic and Research DepartmentUniversity Hospital BaselSwitzerland

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