【摘要】 为了探究线粒体的能量代谢过程,本文以离体大鼠肝脏线粒体为模型,利用多通道、高灵敏度的热活性检测仪TAM III,实时监测了不同线粒体浓度、不同底物、不同缓冲液、几种呼吸抑制剂以及Ca²⁺和线粒体渗透转换孔抑制剂CsA存在时线粒体的能量代谢,获得了完整的热功率―时间曲线,并通过计算得到了线粒体能量代谢的热动力学参数。通过分析发现:（1）线粒体浓度越大,代谢越快;（2）直接底物琥珀酸钠使线粒体代谢更快;（3）高浓度Ca²⁺能够刺激线粒体快速产热,且在长期代谢进程中,线粒体渗透转换孔抑制剂CsA并不能改变Ca²⁺造成的影响;（4）不同缓冲液对线粒体代谢的影响基于其组分的不同,缓冲液中含有呼吸底物;（5）呼吸抑制剂都能抑制线粒体的能量代谢,尤其是复合物IV的抑制剂NaN₃,高浓度下使代谢停止。更多还原

【Abstract】 Isolated rat liver mitochondria were proposed as a model to monitor real-time heat metabolism. A high-throughput and sensitive thermal activity monitor III（TAM III） was used to detect the P-t curves of mitochondria under different conditions, including different mitochondrial concentrations, different substrates, different buffers, respiratory inhibitors, Ca²⁺, and CsA. We determined the thermokinetic parameters through calculation. The results showed that:（1） higher concentration of mitochondria led to faster energetic metabolism;（2） when succinate was the direct respiratory substrate, it promoted mitochondrial metabolism, in contrast to the condition when an indirect substrate, pyruvate, was used;（3） high concentration of Ca²⁺(2.5 mmol·L^-1) stimulated mitochondrial metabolism, however CsA, an inhibitor of mitochondrial permeability transition pores, could not reverse the Ca²⁺-induced mitochondrial alteration;（4） mitochondria in various buffers displayed different rates of heat metabolism, because of the different composition of the buffers;（5） mitochondrial metabolism was inhibited by respiratory inhibitors, especially NaN₃, which is an inhibitor of Complex IV and which completely stopped the mitochondrial heat release.更多还原