Abstract:Abstract: 18 male ApoE-/- mice were divided into the control, heat wave, BH4 group respectively to explore the effects of temperature rising process in heatwaves on SOD in ApoE-/- mice. The groups of heat wave and BH4 were exposed to the simulated heatwave process which is collected from Nanjing City in July of 2001. The body weight and rectal temperature of every mouse were measured every day. Cardiac tissue fluids were collected for SOD activity measurement after the end of the simulation. Compared with the control and BH4 groups, mice’ rectal temperature of the heat wave group increased while the activity of SOD decreased significantly(P <0.01). No significant difference was found between the control group and BH4 group while weight in all groups had no significant change. SOD activity in heart decreased after heat wave. It could cause oxidative damages and lipid metabolism disorders which may lead to the formation of atherosclerosis. So the SOD system may be an important endogenous inhibitory mechanism of coronary heart disease. BH4 can improve the cooling efficiency and SOD activity in the body so that it may reduce the hazards caused by heatwave weather.