The role of the RhoA/rho-kinase pathway in pulmonary hypertension.

The small GTP-binding protein, RhoA, and its downstream effector protein, rho-kinase, have been implicated in the pathogenesis of a number of cardiovascular diseases. The activation of rho-kinase is involved in the development of increased vascular tone, endothelial dysfunction, inflammation, and restenosis; and that the inhibition of rho-kinase has been shown to have a beneficial effect in a variety of cardiovascular disorders. It is our hypothesis that rho-kinase inhibitors promote vasodilation independent of the mechanism that increases vasoconstrictor tone and moreover, the RhoA/rho-kinase pathway has a role in the regulation of smooth muscle tone under physiological conditions. The objective of this review is to improve our current understanding of the role of RhoA/rho-kinase pathway in the regulation of vasoconstrictor tone and the use of rho-kinase inhibitors in the treatment of cardiovascular disorders with an emphasis on pulmonary hypertension.