The role of angiotensin II in regulating vascular structural and functional changes in hypertension.
A major hemodynamic abnormality in hypertension is increased peripheral resistance due to changes in vascular structure and function. Structural changes include reduced lumen diameter and arterial wall thickening. Functional changes include increased vasoconstriction and/or decreased vasodilation. These processes are influenced by many humoral factors, of which angiotensin II (Ang II) seems to be critical. At the cellular level, Ang II stimulates vascular smooth muscle cell growth, increases collagen deposition, induces inflammation, increases contractility, and decreases dilation. Molecular mechanisms associated with these changes in hypertension include upregulation of many signaling pathways, including tyrosine kinases, mitogen-activated protein kinases, RhoA/Rho kinase, and increased generation of reactive oxygen species. This review focuses on the role of Ang II in vascular functional and structural changes of small arteries in hypertension. In addition, cellular processes whereby Ang II influences vessels in hypertension are discussed. Finally, novel concepts related to signaling pathways by which Ang II regulates vascular smooth muscle cells in hypertension are introduced.
Touyz
Rhian M
RM
Clinical Research Institute of Montreal, 110 Pine Avenue West, Canada. touyzr@ircm.qc.ca
D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D017209:Apoptosis; D001158:Arteries / Q000378:metabolism / Q000473:pathology*; D002455:Cell Division; D005355:Fibrosis; D006801:Humans; D006973:Hypertension / Q000473:pathology / Q000503:physiopathology*; D007249:Inflammation; D047908:Intracellular Signaling Peptides and Proteins; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D010084:Oxidation-Reduction; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D015398:Signal Transduction; D014655:Vascular Resistance; D014666:Vasomotor System / Q000502:physiology*; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein / Q000502:physiology
D047908:Intracellular Signaling Peptides and Proteins; D000804:Angiotensin II; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein