Characterization of immunoreactive endothelin in human urine.
We developed three antibodies, specific and sensitive to endothelin-1 (ET-1), and established two sandwich and three competitive enzyme immunoassays (EIAs). By using these EIAs, large immunoreactive ET (IR-ET) of molecular weight 10 k Da was identified as a main component of IR-ETs in human urine. This large IR-ET, which reacted with two antibodies specific for N-terminal region of ET-1 but not with the antibody against C-terminal peptide of ET-1, was partially purified by six-step procedure and examined by Western blotting after SDS polyacrylamide gel electrophoresis. The large IR-ET was detected as a single band at molecular weight of 10 k Da both in reduced and non-reduced conditions. From these results, the large IR-ET was thought to consist of a single polypeptide chain and possess the steric restricted N-terminal region of ET-1.
Arai
K
K
Tokyo Research Laboratories, Kowa Co. Ltd., Japan.
Koshi
T
T
Ehara
Y
Y
Edano
T
T
Ohkuchi
M
M
Hirata
M
M
Okabe
T
T
D000595:Amino Acid Sequence; D000906:Antibodies; D000911:Antibodies, Monoclonal; D015153:Blotting, Western; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions; D016232:Endothelins / Q000276:immunology / Q000302:isolation & purification / Q000652:urine*; D006801:Humans; D007124:Immunoenzyme Techniques
D000906:Antibodies; D000911:Antibodies, Monoclonal; D016232:Endothelins