The Protection Of Esmolol For Immature Ischemic Myocaidium Under Ischemia-reperfusion Injury

Objective:To observe the protective effects of esmolol cardioplegic solution of different doses for immature rats myocaidium under ischemia-reperfusion injuryMethords:Set up the Langendorff- perfused models of isolated immature rat hearts,4℃esmolol cardioplegic solution arrested for 3min,then undergone ischemia for 45min,and reperfusion for 30min,set up the ischemia-reperfusion injury models.Experiments were divided into normal perfusion group(peffused for 95min consecutively),ST.Thomas group,(no esmolol), esmolol group(the concentration of esmolol is 0.5,1.0,2.0 mmol/l)We observed functional indexes including heart rate(HR,min^-1),tension(T_min,g),contraction force(â–³T,g),peak systolic velocity(+dT/dt_max,g/s),peak diastole velocity(-dT/dt_max,g/s),coronary flow(CF,ml/min),recover beat(s)during the lab proc。After the experiments,the hearts were used to measure biochemical indexes of Na⁺-K⁺ ATPase,and observed myocardial histopathology and ultralstructure.Results:Esmolol reduced the tension of the hearts during ischemia,the beat of the hearts was better,enhanced coronary flow;improve Na⁺-K⁺ ATPase activity avoided energy consumption,enhanced antioxigy,ensured myocardial integrality,lightened mitochondrial change.The protection was appropriate in concentration 1.0mmol/L of esmolol during reperfusion.Conclusions:Esmolol can lighten immature myocaidium damage under ischemia reperfusion injury.