SCOR IN HEART FAILURE

这一相互竞争的更新包括六项合作调查， 由四个综合核心设施提供支持，以解决问题 心脏疾病的病因、发病机制和治疗的基础 失败了。这些研究的重点是试图解开分子 两者心脏生长、肥大和衰竭的机制 获得性和遗传性疾病。在项目1-2中，我们将调查 肥厚型心肌病(HCM)和强直性肌张力的分子基础 营养不良(DM)。三种已知β-肌球蛋白的互补DNA构建 重链(BetaMHC)突变将通过E1缺陷表达 猫心肌细胞中的腺病毒并包装成迷你病毒用于体内 在转基因兔中表达。心脏的结构和功能将 在活体内用超声心动图和随后的光连续评估 和电子显微镜来解释β-MHC的后果 突变。在项目2中，利用酵母相互作用克隆和 固定化重组肌钙蛋白激酶作为亲和力的研究 MtPK的底物将被确定为迈向 确定被推定为相关的磷酸化级联中的缺陷 对于DM。在对项目1和项目2的其他研究中，大量信息丰富的家谱 将被分析以确定这两种疾病的新基因 与已建立的基因座相关联。在项目3中，使用一个非常大的 家族性扩张型心肌病家系(&gt；400)，连锁 分析和定位克隆将被用来鉴定 负责任的基因。在项目4中，假设TGFbeta1在 心肌肥厚的评估将使用新的优势- 成人心肌细胞中转化生长因子β受体的阴性突变， 用腺病毒基因转移和在完整心肌中进行转基因 老鼠。在项目5中，p55和p55的野生型和显性-阴性突变体 P75肿瘤坏死因子α受体将通过腺病毒在成人体内表达 测定心肌细胞中肿瘤坏死因子α受体的形态 对收缩能力下降负有责任。受体的一种可溶形式 将作为一种肿瘤坏死因子α抑制剂给予，试图改善心脏 心衰患者的功能及评价内源性激素的作用 体内应用肿瘤坏死因子α。在项目6中，将进行研究以确定 胰岛素样生长因子-I(IGF一I)在心脏发育和心脏发育中的作用 利用高表达胰岛素样生长因子-L或其结合的转基因小鼠进行肥大 蛋白。腺病毒基因转移及其显性-负性突变 假定的IGF信号蛋白将被用来识别 负责任的细胞质转导因子和转录因子 胰岛素样生长因子在心肌肥厚中的作用这六项研究加在一起， 应该会对人类免疫缺陷的分子基础提供重要的新见解 心肌肥厚和衰竭是导致心脏功能不全的合理基础 更有效的治疗方法。

This competing renewal encompasses six collaborative investigations, supported by four integrated core facilities, to address issues fundamental to the etiology, pathogenesis and treatment of cardiac failure. The studies are focused on an attempt to unravel molecular mechanisms underlying cardiac growth, hypertrophy and failure in both acquired and inherited disorders. In Projects 1-2, we will investigate the molecular basis for hypertrophic cardiomyopathy (HCM) and myotonic dystrophy (DM). Complementary DNA constructs with three known beta-myosin heavy chain (betaMHC) mutations will be expressed via E1-deficient adenovirus in feline cardiocytes and packaged into minigenes for in vivo expression in the transgenic rabbit. Cardiac structure and function will be assessed serially in vivo by echocardiography and subsequently by light and electron microscopy to elucidate the consequences of beta MHC mutations. In Project 2, utilizing yeast interaction cloning and immobilized recombinant myotonin protein kinase (MtPK) as an affinity matrix, substrates for MtPK will be identified as an initial step toward identifying the defect in the phosphorylation cascade presumed responsible for DM. In other studies of Projects 1 and 2, large informative pedigrees will be analyzed to identify novel genes for both diseases in families not linked to established loci. In Project 3, using an exceptionally large pedigree (>400) with familial dilated cardiomyopathy (DCM), linkage analysis and positional cloning will be employed to identify the responsible gene. In Project 4, the postulated role of TGFbeta1 in cardiac hypertrophy will be assessed with the use of novel dominant- negative mutants of the TGFbeta receptor in adult ventricular myocytes, using adenoviral gene transfer and in the intact myocardium in transgenic mice. In Project 5, wild-type and dominant-negative mutants of the P55 and P75 TNFalpha receptor will be expressed via adenovirus in adult ventricular myocytes to determine the form of TNFalpha receptor responsible for depressed contractility. A soluble form of the receptor will be given as a TNFalpha inhibitor in an attempt to improve cardiac function in patients with failure and evaluate the role of endogenous TNFalpha in vivo. In Project 6, studies will be performed to determine the role of insulin-like growth factor-I (IGF-l) in cardiac growth and hypertrophy, utilizing transgenic mice overexpressing IGF-l or its binding protein. Adenoviral gene transfer and dominant-negative mutations of postulated IGF signalling proteins will be used to identify the responsible cytoplasmic transducers and transcription factors that mediate the effect of IGF on cardiac hypertrophy. Together, these six studies should provide significant new insights into the molecular foundations of cardiac hypertrophy and failure and contribute to a rational basis for more effective therapy.