| Objective: It thinks that fat tissue is an energy storage depot traditional. In recent years, adipose tissue has emerged as an important endocrine organ producing a variety of secreted factors including TNF-α,IL-6 and IL-8, plasminogen-activator inhibitor type 1 ( PAI-1 ) , leptin, adiponectin, resistin,visfatin, and others。Adipokine plays an important role in metabolism, inflammation, endothelial function, smooth muscle cell and responses to stress. Adipokine also participates in several pathophysiological processes contributing to obesity-related diseases, including hypertension,atherosclerosis, diabetes and metabolic syndrome.Visfatin, an adipokine described firstly in 2005 by Fukuhara et al[1], corresponds to a protein identified previously as pre-B cell colony-enhancing factor (PBEF). Visfatin is expressed predominantly in adipose tissue and mediates insulin-mimetic, anabolic effects through the insulin receptor, lowering plasma glucose levels. Enhanced circulating levels of ePBEF/NAMPT/visfatin have been positively associated not only with increased plasma levels of inflammatory markers[2], but also with vascular damage and endothelial dysfunction[3-4]. An emerging hypothesisis that ePBEF/NAMPT/visfatin might directly promote vascular inflammation, therefore representing a link between metabolic disorders and atherothro- mbotic diseases exhibiting a chronic proinflammatory background, including atherosclerosis and CHD.Visfatin has recently been identified as a protein preferentially expressed in visceral adipose tissue compared with subcutaneous adipose tissue[5]. It can also be found in skeletal muscle, liver, bone marrow, and lymphocytes, where it was initially identified as pre–B-cell colony enhancing factor。Whether cardiocytes could express visfatin, and the expeession of visfatin in angiot- ensinⅡstimulated cardiocytes has not been unknown. In this study, we observe that the influence of different concentrations and time of AngⅡon the expression of visfatin in neonatal rat cardiomyocytes, with the purpose of finding a new pathology of the cardiovascular disease.Methods: Primary culture the cardiomyocytes from the hearts of 2-3 days'neonatal Sprague-Dawley (SD) rats aseptically, regardless of sex. After 48 hours'culture with serum and 24 hours'culture without serum, cells in good conditions are selected and put into 10 groups randomly. There are 5 groups in AngⅡpart.①10-8mol/L AngⅡgroup,②10-7mol/L AngⅡgroup,③10-6mol/L AngⅡgroup,④10-5mol/L AngⅡgroup,⑤control group. There are 5 groups in different stimulation time part.①6 hours group,②12 hours group,③24 hours group,④48 hours group,⑤control group. Culture these cardiomyocytes with different concentrations of AngⅡfor 48 hours and AngⅡ(10-6mol/L) for different time, useβ-actin as the internal control ,then detect the expression of visfatin-mRNA and visfatin-protein with RT-PCR and western- blot.Results:1 Culture the cardiomyocytes from the hearts of 2-3 days'neonatal Sprague-Dawley (SD) rats successfully.2 The OD value of MTT products of cardiomyocytes pretreated with Ang II increased in a dose-dependent manner, peaking when the concentration of Ang II was 10-6 mo1/L, and it dropped significantly when the concentration of Ang II was 10-5mo1/L.3 With the elevation of AngⅡconcentration, the expression of visfatin-mRNA and protein increased in neonatal rat cardiomyocytes.4 The OD value of MTT products of cardiomyocytes was increased in a time- dependent manner, peaking at 12 hours, and it decreased significantly after 24 hours.5 At different periods, visfatin mRNA and protein expression were increased in a time-dependent manner, highest at 24 hours, and decreased significantly after 48 hours. Conclusion: The cardiomyocytes can express visfatin. The higher concentration of AngⅡcan increase the expression of visfatin in cardiomy- ocytes in vitro. As the elevation of AngⅡconcentration, the expression of visfatin in cardiomyocyte also increased. Within 24 hours, the expression of visfatin in cardiomyocytes significantly increased with time. |
PDF Full Text Request