Enhanced cell proliferation in essential hypertension.

In order to define the molecular mechanism involved in enhancement of spontaneously hypertensive rat (SHR) cell proliferation, we have compared the actions of fetal calf serum (FCS) and angiotensin II on both SHR and Wistar-Kyoto (WKY) rat aortic smooth muscle cells. Both compounds are more mitogenic in SHR cells than in controls. However, phospholipase C (PLC) hyperresponsiveness can be seen only under angiotensin stimulation, as are the expressions of c-jun, c-fos, and c-myc. Oncogene overexpression therefore appears to be more strongly related to PLC hyperreactivity than to enhanced proliferation of SHR aortic smooth muscle cells.