Characterization of immunoreactive dynorphin B and beta-endorphin in human plasma
1998 (English)In: Peptides, ISSN 0196-9781, E-ISSN 1873-5169, Vol. 19, no 8, 1329-1337 p.Article in journal (Refereed) Published
Dynorphins and beta-endorphin in human plasma were characterized and studied quantitatively using radioimmunoassay, high-performance liquid chromatography (HPLC), and mass spectrometry. Most immunoreactive (ir) dynorphin B and beta-endorphin in human plasma coeluted with authentic peptides in analysis. Dynorphin A was not detected. Added to human plasma it was rapidly converted into Leu-enkephalin-Arg6 followed by elimination of the C-terminal arginine after prolonged incubation. The rate of dynorphin A conversion was estimated at 40 pmol/min/microl plasma. This process was inhibited by the thiol protease inhibitor, PHMB and by EDTA. Dynorphin B, alpha-neoendorphin and big dynorphin were virtually not metabolized by plasma proteases under the same conditions. beta-endorphin was processed into beta-endorphin(1-19) and the corresponding C-terminal counterpart beta-endorphin(20-31) at a rate of about 25 pmol/min/microl of plasma. Based on the above data, a reliable strategy was established to measure dynorphin B- and beta-endorphin-ir in human plasma samples. The basal levels in a male control group were 0.99 +/- 0.11 (n = 11) and 16.3 +/- 1.5 (n = 11) fmol/ml plasma, respectively.
Place, publisher, year, edition, pages
1998. Vol. 19, no 8, 1329-1337 p.
dynorphins, endorphins, neuropeptides, metabolism, proteases, protease inhibitors, plasma, human, high pressure liquid chromatography, mass spectrometry
Pharmaceutical Sciences Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-50735DOI: 10.1016/S0196-9781(98)00079-5ISI: 000076504700005PubMedID: 9809646OAI: oai:DiVA.org:uu-50735DiVA: diva2:78644