Tufts -- In a study led by Akiko Hata, PhD, of Tufts University School of Medicine, researchers have shown that a protein expressed in the heart, FHL2, inhibits the genes necessary for the quiescence of vascular smooth muscle cells (vSMCs), which line blood vessels. Vascular smooth muscle cells undergo a process in diseases such as atherosclerosis or normal tissue damage caused by balloon angioplasty where they transition between a resting and proliferative state. The ability to transition between the two states is necessary for the normal development of blood vessels, regulating blood pressure, and repairing vessels that suffer from injury.