Circulating endothelin immunoreactivity in the elderly

Abstract

To investigate plasma endothelin behaviour in aging we measured circulating endothelin immunoreactivity in fifteen normal young adults (mean age 25.3±2.2) and nineteen elderly, apparently healthy people (mean age 85.4±3.7). The mean (±SD) plasma endothelin concentrations was 2.04±0.53 pg/ml in the young subjects and 2.6±0.56 pg/ml in the elderly subjects. The difference was statistically significant (p<0.01). The mechanism of the increased plasma endothelin concentrations in the elderly might be multifactorial. In particular the increase of circulating endothelin may reflect a rise in its vascular production in response to endothelial cell injury, due to a clinically silent atherosclerotic process. It therefore has to be established if the increase of circulating endothelin in elderly, apparently healthy people is due only to a physiological aging or also other factors, such as un atherosclerotic process already underway but clinically silent, are involved.