中文摘要：

目的：探讨β3肾上腺素能受体（β3-AR）对SD大鼠乳鼠心肌肥大的影响及其机制。方法：体外培养SD大鼠乳鼠心肌细胞,用携带β3-AR基因的慢病毒转染细胞后,用去甲肾上腺素（NE）诱导细胞48h,建立心肌细胞肥大模型。实验分4组：空白对照组（Control组）、心肌肥厚组（NE组）、β3-AR基因转染＋NE组（β3-AR组）、空病毒转染＋NE组（空病毒组）。用免疫荧光法鉴定心肌细胞,倒置荧光显微镜观察病毒转染组绿色荧光蛋白（GFP）表达,免疫印迹法（Western Blot）检测β3-AR、丝裂原活化蛋白激酶p38（p38MAPK）、细胞外信号调控激酶（ERK1/2）、磷酸化p38MAPK（p-p38MAPK）和ERK（p-ERK1/2）及原癌基因c-myc、c-fos蛋白水平的表达。结果：（1）慢病毒介导β3-AR基因转染心肌细胞,β3-AR表达较空白对照组明显升高。（2）用Western Blot检测各实验组细胞原癌基因c-myc、c-fos表达,其中NE组、β3-AR组、空病毒组表达均高于空白对照组,其中β3-AR组cmyc、c-fos表达明显高于NE组。（3）NE组、β3-AR组、空病毒组p38MAPK及ERK1/2的磷酸化水平较空白对照组明显上调,其中β3-AR组表达最高。结论：慢病毒介导的β3-AR基因转染使心肌细胞有效高表达β3-AR,β3-AR可能通过MAPK通路促进心肌肥厚。

英文摘要：

Objective：To examine the effects of lentivirus mediated β3-adrenoreceptor（β3-AR）gene transfer on cardiac hypertrophy and to elucidate related mechanisms. Method：Rat neonatal ventricular cardiomyocytes（NRVMs）from new born Sprague-Dawley rats were isolated and cultured in vitro.NRVMs were transfected with rat β3-AR gene mediated by lentivirus prior to norepinephrine（NE,2uM）treatment for 48 h.The cultured cardiacmyocytes were randomly divided into four groups：control group,hypertrophy group,β3-AR-lentiviral transfected group and blank lentiviral group.The NRVMs were detected by cTNT immunofluorescence staining.Inverted fluorescence microscope was used to observe the expression of green fluorescent protein（GFP）to examine the efficiency of lentivirus.The β3-AR,mitogen-activated protein kinases（MAPKs）,c-myc and c-fos protein levels were examined by Western Blot.Result：The protein levels of β3-AR were significantly increased in β3-AR-lentiviral transfected group compared with control group and NE group.The protein levels of MAPKs in groups treated with NE expressed more than control group,and the phosphorylation levels of p38 MAPK and ERK1/2 peaked in β3-AR-lentiviral transfected group compared with other three groups.Conclusion：The expression of β3-AR gene were significantly increased in NRVMs transfected by lentivirus.β3-AR contributes to cardiac hypertrophy,and p38 MAPK,ERK1/2 phosphorylation may be the major mediators.