Premium
Detection of immunoreactive endothelin in plasma of hemodialysis patients
Author(s) -
Totsune Kazuhito,
Mouri Toraichi,
Takahashi Kazuhiro,
Ohneda Minoru,
Sone Masahiko,
Saito Takao,
Yoshinaga Kaoru
Publication year - 1989
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(89)80631-3
Subject(s) - radioimmunoassay , chromatography , extraction (chemistry) , endothelin receptor , cartridge , detection limit , chemistry , hemodialysis , endothelin 1 , human plasma , size exclusion chromatography , medicine , biochemistry , materials science , enzyme , receptor , metallurgy
Two types of radioimmunoassay (RIA) methods for measuring endothelin (ET) in human plasma were developed. One was an extraction procedure using a Sep‐Pak C 18 cartridge, the other being a direct method. By the extraction method, plasma ET levels were lower than the detectable limit (7 pg/ml) in normal subjects and elevated in hemodialysis patients. The absolute values obtained via the direct method were 20‐times higher than those from extraction. Gel‐filtration experiments revealed that this discrepancy was mainly due to immunoreactive (IR‐) endothelin‐like substances of high molecular mass near 11.6 kDa (large IR‐ET). Extraction of the peptide by the C 18 cartridge could eliminate interference by large IR‐ET and is important in the accurate measurement of ET concentrations in plasma.