Proliferation and migration of VSMCs (Vascular Smooth Muscle Cells) in arteries plays an important role in the pathophysiology of atherosclerosis, hypertension, and restenosis after angioplasty. A wide variety of growth factors, cytokines, and hormones activate these responses in blood vessels. A prominent growth factor for VSMCs is Angiotensin (Angiotensin-I and II), the main peptide of the Renin Angiotensin System. Renin, an enzyme acts upon a circulating substrate, angiotensinogen that undergoes proteolytic cleavage to form the decapeptide Angiotensin-I. Vascular endothelium, particularly in the lungs, has an enzyme, ACE (Angiotensin Converting Enzyme), that cleaves off two amino acids to form the octapeptide, Angiotensin-II. Multiple signal transduction pathways are involved in mediating Angiotensin receptor stimulation of cell proliferation, cell migration, and other responses. In addition, [...]