Endothelin
Serum concentrations of endothelin were determined using the Quantikine
Endothelin-1 ELISA kit (Biotechne, R&D Systems, Oxon, UK). The
detection limit was 0.09 ng/L with a measurement range of 0.45 to 2.00
ng/L. The intra-assay coefficients of variation for the low and high
concentrations were 4.0% and 1.9%. The inter-assay coefficients of
variation for the low and high concentrations were 7.6% and 5.3%.