尾部悬吊对大鼠胸主动脉氧化应激水平的影响

目的:观察模拟失重对大鼠胸主动脉氧化应激水平的影响,探讨其可能机制。方法:采用3周尾部悬吊大鼠模型模拟失重状态,通过DHE荧光探针技术观察大鼠动脉血管超氧阴离子水平变化,通过比色法测定大鼠动脉血管丙二醛(MDA)含量,通过蛋白印记技术观察悬吊(SUS)大鼠和正常对照(CON)大鼠动脉血管NOX4、p22phox的表达变化。结果:尾部悬吊3周后,SUS组大鼠胸主动脉超氧阴离子水平较CON组明显增高,SUS组(0.849±0.023 nmol/mg protein)大鼠MDA含量较CON组(0.575±0.054nmol/mg protein)明显增加;SUS组大鼠胸主动脉的p22phox及NOX4蛋白表达均较CON组明显增强。结论:模拟失重3周可使大鼠胸主动脉氧化应激水平明显增高,p22phox及NOX4蛋白表达明显增多,结果提示,尾部悬吊模拟失重状态下氧化应激水平增高可能与NADPH氧化酶表达增高有关。

Effects of Hindlimb Unweighting on the Oxidative Stress of Thoracic Aorta in Rats

Objective:To investigate the level of oxidative stress in tail suspended rats and the mechanism.Methods: 3-week tail suspended rats were adopted as the animal model of simulated microgravity.DHE fluorescent probe technique was applied to evaluate the level of superoxide anion.Colorimetry was taken to detect the MDA content.Western blot analysis was taken to compare the expression of NOX4 and p22phox between the SUS and CON groups.Results: Compared with CON,the level of superoxide anion enhanced significantly in SUS rats,while the content of MDA increased in SUS rats.The expression of both p22phox and NOX4 increased in SUS rats as a result of 3-week simulated microgravity.Conclusion: The level of oxidative stress in rats increased by 3-week simulated microgravity,and increased ROS level in tail suspended rats might associated with the enhanced expression of NADPH oxidase.