Pathophysiology of primary hypertension

Abstract

The increased peripheral resistance is considered the major cause of primary hypertension. The functional and structural factors responsible for the resistance vascular changes in hypertension are reviewed. The most important functional mechanisms acting on the resistance vessels are represented by pressor (neurogenic, angiotensin, vasopressin, endotelin, etc) and depressor. (NO, prostacyclin, atrial natriuretic peptide etc) factors. The increased activity of the vascular effector cells depends on complex influences ascribed to an imbalance of production between the pressor and depressor factors. The structural mechanism is represented by an increase in the media/lumen ration of the resistance vessels. The reduction in lumen can be produced by growth of the wall into the lumen (hypertrophy) or by a rearrangement of the amount of material around the smaller lumen (remodeling). Finally, the importance of genetic predisposition in hypertension and of genetic defects, presently analysed by powefull molecular biology methods were reviewed.