ETIOLOGY AND DEVELOPMENT OF CONGENITAL HEART DISEASE

具有遗传性心血管病变特异性缺陷的犬品系 应用发展研究圆锥干间隔的发病机制 畸形(包括法乐四联症、室间隔缺陷症和 永久性动脉干)、肺动脉瓣发育不良和未闭 动脉导管。比较受影响菌株的胚胎和正常菌株的胚胎 将胚胎控制在可比的发育阶段，调查 通过经典胚胎学研究时间进程的进展 发育中的心脏形状和形式的异常，以 研究了细胞增殖、差异细胞死亡、 和细胞间基质的形成在这些疾病的发生中 畸形。使用的方法包括蜡板重建术 从连续切片中发育心脏，透射电子显微镜， 心脏显微解剖的扫描电子显微镜和Quantimet 细胞与细胞外基质的相对体积分析 取自发育中心脏特定区域的切片。量化 利用细胞学进行有丝分裂活性和细胞死亡的形态计量学研究 技巧。放射自显影用于评估细胞复制 (将氚胸腺嘧啶核苷掺入DNA) 区域。

Strains of dogs with hereditary lesion-specific defects in cardiovascular development are used to study the pathogenesis of conotruncal septum defects (including tetralogy of fallot, ventricular septal defect, and persistent truncus arteriosus), pulmonary valve dysplasia, and patent ductus arteriosus. Comparing embryos from affected strains with normal control embryos at comparable stages of development, the investigations progress through classical embryologic studies of the time course of abnormalities in the shape and form of the developing heart, to investigation of the roles of cell proliferation, differential cell death, and formation of intercellular matrix in the genesis of these malformations. Methods used include wax plate reconstruction of the developing heart from serial sections, transmission electron microscopy, scanning electron microscopy of microdissected hearts, and Quantimet analysis of the relative volumes of cell vs extracellular matrix in sections from selected areas of the developing heart. Quantitative morphometric studies of mitotic activity and cell death utilize cytologic techniques. Autoradiography is used to assess cell replication (incorporation of tritiated thymidine into DNA) in sections from selected areas.