本研究旨在探讨肉碱对运动训练大鼠肝脏细胞线粒体电子传递链及氧自由基代谢的影响。将雄性Wistar大鼠40只随机均分为4组(n = 10)：对照组、肉碱组、训练组和训练+肉碱组。训练组和训练+肉碱组进行递增负荷水平跑台运动训练，肉碱组和训练+肉碱组每日灌胃口服肉碱(300 mg/kg)一次，每周6天，共处理6周。6周后各组大鼠均进行力竭运动，随后立刻取肝脏样本，用差速离心法提取肝脏线粒体，分光光度法测定线粒体电子传递链酶复合体I~IV (CI~IV)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活性及丙二醛(MDA)含量。结果显示，与对照组相比，肉碱组CIV活性显著升高(P < 0.05)，训练组CI、CIII、CIV活性均显著升高(P < 0.05或P < 0.01)，训练+肉碱组CI~IV活性均显著升高(P < 0.05或P < 0.01)；与肉碱组和训练组相比，训练+肉碱组CI和CIV活性均显著升高(P < 0.05或P < 0.01)。与对照组相比，训练+肉碱组SOD活性显著升高(P < 0.01)，肉碱组、训练组和训练+肉碱组GSH-Px活性均显著升高(P < 0.05或P < 0.01)，训练组和训练+肉碱组MDA水平均显著降低(P < 0.05或P < 0.01)；与肉碱组相比，训练+肉碱组GSH-Px活性显著升高(P < 0.01)；与肉碱组和训练组相比，训练+肉碱组SOD活性均显著升高(P < 0.05或P < 0.01)，MDA水平均显著降低(P < 0.01或P < 0.05)。以上结果提示，运动训练及补充肉碱均可提高肝脏线粒体电子传递链功能及抗氧化能力，且运动训练与肉碱的作用具有协同效应。
[Effects of carnitine on respiratory chain and metabolism of oxygen radical in mitochondria of liver after exhaustive running in training rat.] [Article in Chinese]
LI Jie*, CHEN Li
College of Physical Education, Northwest Normal University, Lanzhou 730070, China
The aim of the present study was to investigate the effect of carnitine on cellular respiratory chain and metabolism of oxygen radical in mitochondria of liver after exhaustive running in training rats. Forty male Wistar rats were randomly divided into 4 groups (n = 10): control, carnitine, training and training+carnitine groups. The training and training+carnitine groups received 6-week treadmill training, whereas carnitine and training+carnitine groups were administrated intragastrically with carnitine (300 mg/kg per d) for 6 weeks. After exhaustive running, all the groups were sacrificed to obtain liver samples, and liver mitochondria were extracted by differential centrifugation. Spectrophotometric analysis was used to evaluate activities of respiratory chain complexes (RCC) I-IV, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the content of malondialdehyde (MDA) in the liver mitochondria. The results showed that, compared with the control group, the carnitine group exhibited increased RCCIV activity (P < 0.05), the training group exhibited increased RCCI, RCCIII and RCCIV activities, and the training+carnitine group showed increased RCCI-IV activities (P < 0.05 or P < 0.01). Moreover, RCCI and RCCIV activities in the training+carnitine group were higher than those in the carnitine and training groups (P < 0.05 or P < 0.01). Compared with the control group, the training+carnitine group showed increased SOD activity (P < 0.01), the carnitine, training and training+carnitine groups showed increased GSH-Px activities (P < 0.05, P < 0.01), and the training and training+carnitine groups showed decreased MDA contents (P < 0.05, P < 0.01). The training+carnitine group showed increased GSH-Px activity compared to that in the carnitine group (P < 0.01).The SOD activity in the training+carnitine group was higher than those in the carnitine and training groups (P < 0.05 or P < 0.01), and the MDA level in the the training+carnitine group was lower than those in the carnitine and training groups (P < 0.01). These results suggest that training and carnitine can increase the function of respiratory chain and antioxidant capacity in liver mitochondria, and the improving effects of training and carnitine can be synergistic.
通讯作者：李洁 E-mail: firstname.lastname@example.org
李洁, 陈莉. 肉碱对运动训练大鼠肝脏细胞线粒体电子传递链及氧自由基代谢的影响[J]. 生理学报 2012; 64 (4): 463-468.
LI Jie, CHEN Li. [Effects of carnitine on respiratory chain and metabolism of oxygen radical in mitochondria of liver after exhaustive running in training rat.] [Article in Chinese] . Acta Physiol Sin 2012; 64 (4): 463-468 (in Chinese with English abstract).