Relevance of vascular structural and smooth muscle sensitivity changes in hypertension

This is a mini-review of the vascular changes that occur in experimental hypertension. Augmented vascular resistance and reactivity appear to be due to an increase both in wall thickness and in vascular smooth muscle sensitivity. The increase in wall thickness is an adaptive change that is secondary to the increase in arterial pressure; the altered smooth muscle sensitivity occurs in the absence of an increase in arterial pressure and hence may initiate the increase in vascular resistance and reactivity of experimental hypertension. Studies of subcellular function indicate that changes in smooth muscle sensitivity may be caused by an increase in cell membrane permeability and an altered handling of calcium by its subcellular sequestering system.