Changes in nuclear calcium content and permeability of nuclear pore complex in rat myocardium during ischemia reperfusion injury / 中国病理生理杂志

ABSTRACT

AIM: To investigate the changes in nuclear calcium content and permeability of nuclear pore complex in rat myocardium during ischemia reperfusion injury.METHODS: The rat model of myocardial ischemia reperfusion injury was established.Myocardial nuclei were purified using sucrose density gradient centrifugation.The nuclear calcium content was measured by atomic absorption spectrophotometer.The permeability of nuclear pore complex was assessed through measuring the amount of calmodulin conjugated Alexa Fluo~(TM) 488 as fluorescent probes transported across nuclear membrane with spectrofluorometer.RESULTS: The nuclear calcium content at 15,30,60,120 and 180 min reperfusion following 30 min sustained ischemia increased 1.31-,1.55-,1.73-,1.94-and 2.14-fold,respectively,as compared with sham-operation group.The permeability of nuclear pore complex at 15 min reperfusion following 30 min sustained ischemia showed no difference from sham-operation group,but it only increased 1.31-,1.38-,1.40-,and 1.48-fold at 30,60,120 and 180 min reperfusion following 30 min sustained ischemia compared with sham-operation group.CONCLUSION: The nuclear calcium content during myocardial ischemia reperfusion injury increases earlier than the permeability of nuclear pore complex does.The increase in the permeability of nuclear pore complex may result in adaptive regulatory effects on nuclear calcium overload to a certain extent during myocardial ischemia reperfusion injury.