Alternation of mitochondrial Oxidative phosphorylation post-ischemia/reperfusion myocardial injury in mice / 实用医学杂志

ABSTRACT

Objective To investigate the alternation of mitochondrial oxidative phosphorylation post-ischemia/reperfusion myocardial injury in mice. Methods The C57BL/6 mice were randomly divided into five groups. The mouse hearts in the time control group (TC) were perfused for 45 min in identical Krebs-Henseleit buffer without any treatment. In the ischemia/reperfusion groups, the mouse hearts were treated with different reperfusion time including 5, 10, 15 or 30 min, following by the same ischemia period of 25 min. The mitochondria were extracted from the left ventricular post-reperfusion. The respiratory function including R3, R4, RCR, and the maximal rate of state 3 respiration (2 mmol/L ADP) were measured. Results The R3, RCR and P/O of mitochondria, using glutamate + malate as substrates, were decreased significantly at 10 min, 15 min and 30 min post-ischemia/reperfusion (P < 0.05, respectively), but not in the 5-min-reperfusion group compared with the time control group. And the respiratory function, using succinate, and TMPD-ascorbate as substrates, decreased significantly in different ischemia/reperfusion groups compared with the time control (P < 0.05, respectively). Conclusions The mitochondrial respiratory function changes differently in different complex at the early stage of reperfusion after ischemia. So different ischemia/reperfusion time should be chosen to detect the alternations of different mitochondrial complex after heart injury.