Effects of prolonged cold storage in cardioplegic solution on mitochondria in isolated hearts

Wang Yihan; Li Shuanglei; He Xiaoyi; Xiao Cangsong

doi:10.13498/j.cnki.chin.j.ecc.2025.02.12

Abstract：Objective To investigate the effect of cardioplegic solution(HTK)on isolated rat hearts during prolonged cold storage,observing changes in hemodynamics and cardiac tissue structure,and preliminarily explorring the effects of HTK on myocardial mitochondria under cold storage conditions.Methods 24 male SD rats weighing 280-360 g were randomly divided into three groups:sham group,HTK cold storage for 8 hours(HTK-8)and 12 hours(HTK-12).Cardiac hemodynamic changes were recorded using the Langendorff device,and structural changes in myocardial tissue were observed using HE staining,changes in cardiomyocyte mitochondria were assessed through transmission electron microscopy,and the expression of mitochondria-associated proteins was detected by Western blot.Results In terms of hemodynamics,the recovery rate of pump function and maximum end-diastolic pressure were significantly higher in HTK-8 than in HTK-12,with a statistically significant difference(P<0.05).HE staining showed that the cardiomyocyte structure of HTK-8 was relatively intact,and the degree of interstitial edema,cell swelling and fat changes were significantly less severe than that of HTK-12.Transmission electron microscopy showed mitochondrial swelling and cristae disruption in both HTK-8 and HTK-12 groups,but the changes were less severe in the HTK-8 group.In terms of mitochondrial function,the two proteins regulating mitochondrial fission and fusion changed significantly with the extension of preservation time,suggesting impaired mitochondrial function.Conclusion Prolonged cold storage of isolated hearts exacerbates mitochondrial structural and functional damage,contributing to overall cardiac function.