Transactivation of the insulin-like growth factor-I receptor by angiotensin II mediates downstream signaling from the angiotensin II type 1 receptor to phosphatidylinositol 3-kinase.

Angiotensin II (AngII) activates phosphatidylinositol 3-kinase (PI3-kinase), a known effector of receptor tyrosine kinases. Treatment of smooth muscle cells with AngII has also been shown to promote phosphorylation of various tyrosine kinase receptors. We therefore investigated the relationship between AngII and IGF-I receptor activation in smooth muscle cells with a phosphorylation-specific antibody.

NF-kappaB activation is essential for angiotensin II-dependent proliferation and migration of vascular smooth muscle cells.

Angiotensin II (AngII) functions as a stress hormone under conditions of stretch, pressure and injury to stimulate smooth muscle cell migration and proliferation. Since the cellular response to stress is mediated in part by the transcription factor NF-kappaB, the relationship between AngII and NF-kappaB was investigated. Our study revealed that AngII promoted a dose-dependent and transient phosphorylation of the regulatory IkappaBalpha protein in smooth muscle cells from porcine coronary artery, with concomitant nuclear translocation of NF-kappaB and increased binding to a kappaB promoter element.