Abstract：Objective To investigate the correlation between uncoupling protein 2(UCP2) expression and myocardial mitochondria injury in rats with sepsis induced by lipopolysaccharide(LPS).Methods The rat model of sepsis was established through an intraperitoneal injection of LPS.Forty male Sprague-Dawley rats were randomly and equally divided into control group(an intraperitoneal injection of normal saline), sepsis 6 h group(LPS-6 h group), sepsis 12 h group(LPS-12 h group), sepsis 24 h group(LPS-24 h group), and sepsis 48 h group(LPS-48 h group).The serum and heart tissues were harvested at corresponding time points and myocardial mitochondria was extracted.The microplate reader was applied to measure creatine kinase(CK), creatine kinase-MB(CK-MB), and reactive oxygen species(ROS).Flow cytometry was applied to measure the degree of mitochondrial swelling and mitochondrial membrane potential(MMP).Western blot was used to measure the expression level of UCP2.Electron microscopy was applied to observe the morphological changes in heart tissues and myocardial mitochondria.Results Compared with the control group, the LPS groups had significantly increased serum levels of CK, CK-MB, and myocardial ROS, as well as a significantly increased degree of mitochondrial swelling(PPPr=0.796 and 0.893, respectively;Pr=-0.903, PConclusions In the rat model of sepsis, the myocardium and myocardial mitochondria have obvious injuries, and the expression level of UCP2 is closely correlated with mitochondrial injury.Therefore, UCP2 might play an important role in myocardial mitochondrial injury in sepsis.
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