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目的:探索长链非编码RNA B230352I09基本生物学特征及其在心肌损伤过程中的作用。方法:利用UCSC网站（http://genome.ucsc.edu）分析lncRNA B230352I09的生物学特征；通过catRAPID预测B230352I09可能结合蛋白；使用实时荧光定量（RT）PCR方法检测lncRNA B230352I09在小鼠出生后7 d内不同时间点（0、1、3、7ｄ）的心脏组织中的表达情况；lncRNA B230352I09在新生小鼠器官分布表达情况；lncRNA B230352I09在心肌损伤小鼠心脏中的表达规律。培养原代心肌细胞，构建缺氧模型，采用Hoechst染色试剂盒检测lncRNA B230352I09过表达对缺氧心肌细胞凋亡的影响；DCFDA探针法检测lncRNA B230352I09过表达对缺氧心肌细胞ROS含量影响；JC-1荧光探针检测缺氧心肌细胞线粒体膜电位变化。结果:LncRNA B230352I09在小鼠基因组定位于7号染色体:123031415-123066439 forward strand，全长663 bp。与该lncRNA相邻基因为Rbbp6。通过catRAPID预测lncRNA结合蛋白显示Rbbp6可能为B230352I09的作用靶标。随着心脏发育，lncRNA B230352I09表达水平呈逐渐下降趋势。lncRNA B230352I09在新生1 d小鼠心、脑、肾、肝组织中均有表达；进一步取心脏组织提取心肌细胞检测发现lncRNA B230352I09在非心肌细胞中的表达量明显少于心肌细胞[(1.0±0.03) n vs. (9.2±3.29)，n P=0.013]。lncRNA B230352I09在心肌损伤后表达水平随时间呈现逐渐下降趋势，而相对正常发育小鼠lncRNA B230352I09表达量增多，但差异无统计学意义。Hoechst染色发现lncRNA B230352I09可抑制缺氧后心肌细胞凋亡；检测心肌细胞ROS的含量显示，和缺氧组比较，lncRNA B230352I09过表达组心肌细胞ROS生成明显减少([(3.8±0.71) n vs. (1.65±0.56)，n P=0.015])；使用JC-1荧光探针检测线粒体的膜电位，结果显示lncRNA B230352I09过表达组心肌细胞线粒体膜电位较缺氧组明显增高。n 结论:LncRNA B230352I09在心脏组织中主要表达于心肌细胞；在小鼠心肌损伤过程中具有保护作用，主要通过减少心肌细胞凋亡、减少ROS生成、保护心肌细胞线粒体膜电位发挥作用。“,”Objective:To explore the basic biological characteristics of lncRNA B230352I09 and its role in the process of myocardial injury.Methods:We analyzed the biological characteristics of lncRNA B230352I09 on the UCSC website and predicted the possible binding protein of lncRNA B230352I09 by the catRAPID. Real-time fluorescence quantitative (RT) PCR method was applied to detect the expression of lncRNA B230352I09 in heart tissues at different time points (0, 1, 3, 7d) within 7 days after birth, the organs distribution and expression of lncRNA B230352I09 in neonatal mouse and the expression pattern of lncRNA B230352I09 in the heart of mice with myocardial injury. In addition, we constructed hypoxia model by culturing primary cardiomyocytes to detect the effect of lncRNA 230352I09 overexpression on hypoxic cardiomyocyte apoptosis by Hoechst staining kit, the effect of lncRNA B230352I09 overexpression on ROS content of hypoxic cardiomyocyte by DCFDA probe and changes in mitochondrial membrane potential of hypoxic cardiomyocytes by JC-1 Fluorescent probes.Results:Full-length of mouse B230352I09 was 663bp, located in the chr7:123031415-123066439 forward strand. RBBP6 gene was adjacent to B230352I09, which may be the target of lncRNA B230352I09 by catrapid prediction analysis. With the development of the heart, the expression level of lncRNA B230352I09 showed a gradual downward trend. The main expression organs of lncRNA B230352I09 in 1-day-old mice were heart, brain, kidney and liver. In heart tissue, lncRNA B230352I09 expression in non-cardiomyocytes was significantly less than in cardiomyocytes [ (1.0± 0.03) n vs. (9.2± 3.29), n P=0.013]. After myocardial injury, the expression level of lncRNA B230352I09 showed an increasing trend compared with the normal developing mice, but there was no statistical significance. Hoechst staining showed that lncRNA B230352I09 could inhibit the apoptosis of hypoxic cardiomyocytes. Detecting the content of ROS in cardiomyocytes showed that compared with the hypoxia group, the generation of ROS was significantly reduced in the lncRNA B230352I09 overexpression group ([(3.8±0.71) n vs. (1.65±0.56), n P=0.015]). JC-1 fluorescent probe was used to detect the mitochondrial membrane potential, and the results showed that the mitochondrial membrane potential of cardiomyocytes in the lncRNA B230352I09 overexpression group was significantly higher than that in the hypoxia group.n Conclusions:In heart tissue, lncRNA B230352I09 was mainly expressed in cardiomyocytes. LncRNA B230352I09 has a protective effect in the process of myocardial injury in mice, mainly by inhibiting apoptosis of cardiomyocytes, reducing ROS production, and protecting mitochondrial membrane potential of cardiomyocytes.