Assessing Endothelial Dysfunction

The fourth session was opened by a lecture by Dr. Westermeier on endothelial dysfunction in ME/CFS, an imbalance of substances that dilate and constrict blood vessels. Nitric oxide (NO) is a messenger molecule in cardiovascular processes, which leads to the relaxation of the vessels and the heart and the formation of new vessels, while also preventing the formation of blood clots. NO, which promotes blood flow, normally increases after exercise, but in ME/CFS patients its formation in the vessels is reduced. In studies, vascular cells were incubated with blood plasma from ME/CFS patients in vitro, these cells also showed reduced production of NO. The underproduction of NO can be explained by a lack of the amino acid L-arginine. There were also differences in endothelial dysfunction with regard to gender and the severity of ME/CFS symptoms.