【摘要】 在培养的大鼠心肌细胞的培养基中加入0.42×10~-3 mol/L黄嘌呤及5.3×10~-9 mol/L黄嘌呤氧化酶可使心肌细胞产生氧化损伤,表现为APA、MDP、OS、Vmax减小,SDF增大;膜输入阻抗减小;细胞自由基含量增加;细胞的超微结构被破坏。向培养基中加0.0625ppm,Cu可阻止黄嘌呤及黄嘌呤氧化酶的氧化损伤作用。铜作为超氧化构歧化酶及细胞色素氧化酶的活性中心成份,可能通过提高这些酶的活性而起抗氧化及清除自由基作用。更多还原

【Abstract】 Xanthine-xanthine oxidase (X-XOD) added to the culture medium of cultured cardiac cells in rats may damage the cell membrane.Electrophysiological findings indicated that the action potential amplitude (APA) , the maximum diastolic potential(MDP), the threshold potential (TP), the overshoot(OS) and the maximum depolarizing velocity (Vmax) were decreased and the spontaneous discharge frequency (SDF) was increased,while the membrane input impedance was decreased. Electron spin resonance showed that contents of free radicals in cultured cardiac cells were increased. Electron microscopy indicated that ultrastructure of the cardiac cells was destroyed. Supplementation of proper amount of copper could protect the cells from being damaged by X-XOD. As a portion of the essential groups of superoxide dismutase (SOD), copper may function as superoxide free radical scavenger by increasing the activity of SOD.更多还原