Endothelial Dysfunction and Essential Hypertension

Systemic hypertension is a chronic disorder of cardiovascular system characterized by an increase in systemic vascular resistance (SVR). Although the level of blood pressure is a product of SVR and cardiac output, it is the former which is responsible for chronic blood pressure elevation. A number of biochemical, biophysical, and neuro-humoral factors participate in the maintenance of SVR. Whatever the underlying molecular mechanism may be for elevated SVR, the end consequence is endothelial dysfunction. Normal endothelium promotes vasodilation and prevention of local thrombotic phenomena whereas abnormal endothelium promotes vasoconstriction and thrombotic processes. One of the basic pathophysiological aberrations in hypertension is abnormal endothelial function. A number of blood pressure lowering strategies (life-style modification and or anti-hypertensive drugs) result in reversing endothelial dysfunction in hypertension. Thus, endothelial function is considered both as a mechanism and a therapeutic target in hypertension. This review summarizes the physiology and pathophysiology of endothelium in hypertension.