ObjectiveTo investigate the expression and significance of CD73 in rats with intermittent hypoxia and high fat diet.MethodsThe rat model of chronic intermittent hypoxia combined with high fat diet was established. Twenty-four healthy male Wistar rats in the SPF level were randomly divided into 4 group, with 6 rats in each group, namely group A (normoxia and normal diet), group B (normoxia and high fat diet), group C (intermittent hypoxia and normal diet)and group D (intermittent hypoxia and high-fat diet). After 6 weeks of experiment, the serum lipid levels, myocardial morphological changes under microscope, the expression level of CD73 protein detected byimmunohistochemistry and Western blot in myocardial cells in rats were compared among these groups.ResultsThe serum lipid levels were significantly different among these groups (P<0.05). HE results showed that the myocardial cells of group A had no obvious abnormalities; disorganized visible myocardial fibers with focal necrosis in groups B and C; myocardial cell injury was most obvious in group D, in which visible muscle fibers arranged in disorder, and grain was not clear, part of the muscle fibers were dissolved predominantly. Compared with group A, CD73 protein expression levels in myocardial cells in groups B, C, and D were significantly elevated (P<0.01). Furthermore, CD73 protein expression level in myocardial cells in group D was significantly higher than those in groups B and C (P<0.01). Western blot showed consistent results as immunohistochemistry: compared with group A, CD73 protein expression levels in groups B, C, and D were significantly elevated (P<0.05), and CD73 protein expression level in myocardial cells in group D was significantly higher than those in groups B and C (P<0.01).ConclusionChronic intermittent hypoxia and high fat diet can cause myocardial cell damage and upregulate CD73 expression in the cardiomyocytes.