Used for the quantitative measurement of Endogenous Endothelin-1 (ET-1) levels in human serum, plasma, or cell culture samples. This ELISA kit enables researchers to assess ET-1 concentration, which plays a key role in vascular function and is associated with cardiovascular diseases such as hypertension, heart failure, and atherosclerosis. It is widely used in clinical research and drug development to monitor changes in ET-1 expression under different physiological or pathological conditions. The assay provides high sensitivity and specificity, allowing accurate detection of low-abundance ET-1 in small sample volumes.