ETIOLOGY AND DEVELOPMENT OF CONGENITAL HEART DISEASE

这项研究的长期目标是获得一个完整的 对两种疾病的遗传和分子机制的理解 遗传性先天性心脏病：圆锥干畸形(CTD) 动脉导管未闭(PDA)。这些将在胚胎和 胎儿的独特线条是人类缺陷的准确模型。 在CTD系列中，将检验以下具体假设：1. 圆锥干间隔发育异常，产生室间隔 房间隔缺损、法洛四联症或永存动脉干 与全身性右室发育不全有关 早期胚胎心肌；2)肌球蛋白表达异常 受累心肌中的心室轻链；3)单个主要的 基因突变是CTD品系缺陷的基础，该基因可能有 与肌球蛋白基因座相一致或相关联。在PDA产品线中， 将检验以下假设：1)内膜增厚失败 在受影响的PDA系胎儿的动脉导管中与 基因决定的透明质酸蓄积障碍 (HA)内膜下区域；2)动脉导管(DA)特异性蛋白 最近在血管内皮细胞和血管内皮细胞中发现的分子 正常绵羊DA在正常狗DA中存在，但其中一个或两个都缺失 在遗传PDA品系中的狗。要使用的方法包括定量 心肌和心肌有丝分裂细胞的形态计量学和BrdU标记 胚胎心脏垫层组织的分布分析 用蛋白凝胶技术研究胚胎和胎儿心肌肌球蛋白轻链 电泳法(1D、2D PAGE)和抗这些蛋白质、DNA的抗体 南方杂交限制性片段长度多态性(RFLP)研究 CTD基因与肌球蛋白基因和其他基因的连锁。掌上电脑研究 包括胎儿体内HA的免疫组织化学和生化分析 新生儿期动脉导管内膜增厚，细胞培养 多巴胺、肺动脉和主动脉的放射性标记蛋白质分析 细胞通过十二烷基硫酸钠-PAGE和放射自显影，并使用单特异性抗体 目的：研究导管特异性蛋白在原位的分布。

The long term objective of this research is to obtain a complete understanding of the genetic and molecular mechanisms underlying two hereditary forms of congenital heart disease: Conotruncal defects (CTDs) and patent ductus arteriosus (PDA). These will be studied in embryos and fetuses of unique lines that are accurate models of the human defects. In the CTD line, the following specific hypotheses will be tested: 1. Abnormal development of the conotruncal septum, producing ventricular septal defect, tetralogy of Fallot, or persistent truncus arteriosus, is associated with a generalized failure of growth of right ventricular myocardium in early embryos; 2) There is abnormal expression of myosin ventricular light chains in the affected myocardium; 3) A single major gene mutation underlies the CTD line defect and this gene may have identity with or be linked to myosin gene loci. In the PDA line, the following hypotheses will be tested: 1) The failure of intimal thickening in the ductus arteriosus of affected PDA line fetuses is associated with a genetically-determined block in the accumulation of hyaluronic acid (HA) in the subintimal region; 2) Ductus arteriosus (DA) specific protein molecules recently identified in endothelial and smooth muscle cells of the normal lamb DA are present in normal dog DA but one or both is absent in the hereditary PDA line dogs. Methods to be used include quantitative morphometry and BrdU-labelling of mitotic cells of the myocardium and cushion tissue of the embryonic heart, analysis of the distribution of myosin light chains in embryonic and fetal myocardium using protein gel electrophoresis (1D, 2D PAGE) and antibodies against these proteins, DNA Southern blot restriction fragment length polymorphism (RFLP) studies of linkage of the CTD gene to myosin genes and other genes. PDA studies include immunohistochemical and biochemical analysis of HA in the fetal and neonatal ductus arteriosus during intimal thickening, cell cultures analysis of radiolabeled proteins of DA, pulmonary artery, and aortic cells by SDS PAGE and autoradiography, and use of monospecific antibodies to study the distribution of the ductus-specific proteins in situ.