Normal Perfusion of Isolated Rat Hearts and Its Influence on Interfibrillar and Sub-sarcolemmal Mitochondria Activities

Obvious lack of interfibrillar mitochondria (IFM) sub population in isolated mitochondria attributed to limitations in isolation procedure. In this manuscript, we compared the functional activities of mitochondrial sub-populations namely, IFM and sub-sarcolemmal (SSM) mitochondria obtained from isolated rat heart subjected to different perfusion time namely (minutes) 0.5,5,10,25,60 and 120. Prolonged perfusion of isolated rat heart reduced oxidative phosphorylation capacity in both IFM and SSM, but was distinct among the subpopulations. However, mRNA expression level of ND4, CYT B and ATP 6 and resazurin activity were similar in both IFM and SSM. Even though overall function of myocardium is unchanged, mitochondrial subpopulations were distinct in electron transport chain activities, emphasizes the requirement to assess mitochondrial function as distinct subpopulation rather than whole entity.