Description
Systemic arterial smooth muscle cells are exposed to a broad range of oxygen concentrations under physiological conditions. Hypoxia can modulate the proliferative response of smooth muscle cells leading to speculation about its role in vasculogenesis, vascular remodelling and the pathogenesis of arterial disease. The effect of hypoxia has been inconsistent, however, with both enhanced proliferation and growth arrest reported. Nevertheless, these reports support an important effect of hypoxia on smooth muscle cell proliferation and, given its physiological and clinical relevance, this requires clarification. We posited that variation in O2 concentration, within the range that exists in vivo, may have different effects on the proliferation and survival of vascular smooth muscle cells.