In this study, we asked if biologically significant and consistent vascular and cardiac effects can be observed in rats inhaling a) DEP, which increases vasoconstriction in humans (Peretz et al. 2008) and accelerates atherosclerosis in apolipoprotein E–null (ApoE−/−) mice (Campen et al. 2010; Peretz et al. 2008); b) ozone, which produces marked cardiophysiological effects in rats (Uchiyama et al. 1986); or c) ozone + DEP. The gene discussed is APOE; the disease is atherosclerosis.