[Endothelin-1 and endothelin-3 in the plasma of dogs].

The endothelins represent a family of peptides with potent vasoconstrictory effects indicating a role in the regulation of vascular tone. An involvement of endothelins in the pathogenesis as well as pathophysiology of vascular diseases has been proposed. Therefore, the aim of the presented study was to develop the methodology to measure and characterize endothelin-1 (ET-1) and endothelin-3 (ET-3) in the plasma of dogs. Extraction of acidified plasma samples was performed by use of Sep-Pak C18 cartridges and plasma levels of ET-1- and ET-3-immunoreactivity (ET-1-IR; ET-3-IR) were determined by specific radioimmunoassays. The measured ET-immunoreactivities were verified by separation of plasma using high-pressure liquid chromatography (HPLC).