Waldo K L, Willner W, Kirby M L
Department of Anatomy, Medical College of Georgia, Augusta 30912.
Am J Anat. 1990 Jun;188(2):109-20. doi: 10.1002/aja.1001880202.
The objective of this study was to determine how the coronary artery stems develop in the chick embryo. The hearts of 51 ink-injected and cleared chick embryos, aged embryonic days 6, 6.5, 7, 7.5, 9, and 10, were dissected, examined, and selectively photographed. Two representative hearts from each group were paraffin embedded, serially sectioned at 10 microns, and examined for aortic endothelial budding. We found that the proximal coronary artery did not appear to grow outward from the aorta as commonly described in the literature. It appeared to originate from a capillary ring which encircled the aortic and pulmonary outflow tracts. On embryonic day 7.5, one to three channels arising from this ring penetrated each aortic sinus, in an area of darker textured endothelium. Histologically and grossly, multiple channels were still apparent on day 9, particularly in the left coronary artery. One of these channels always became dominant to form the stem. Each stem, which varied in length from embryo to embryo, always ended in a plexus of sinusoidal endothelial tubes. By day 10, the coronary artery stems were longer, with many major branches. Histologically, evidence of multiple channels still was visible. It is significant that channels from the bulbar vascular ring penetrated the aorta at very specific points in the aortic sinuses and did not penetrate the pulmonary trunk or other aortic sites. We believe this fact indicates that the penetration of the aortic sinuses by channels from the bulbar vascular ring represents a controlled invasion of the aorta.
本研究的目的是确定鸡胚冠状动脉干如何发育。对51个注射墨水并进行透明处理的鸡胚心脏进行了解剖、检查和选择性拍照，这些鸡胚的年龄分别为胚胎第6、6.5、7、7.5、9和10天。每组选取两个代表性心脏进行石蜡包埋，以10微米的厚度连续切片，并检查主动脉内皮出芽情况。我们发现，近端冠状动脉并非如文献中通常描述的那样从主动脉向外生长。它似乎起源于一个环绕主动脉和肺动脉流出道的毛细血管环。在胚胎第7.5天，从这个环发出的一到三条通道穿透每个主动脉窦，位于内皮纹理较深的区域。在组织学和大体观察上，第9天时多条通道仍然明显，尤其是在左冠状动脉中。其中一条通道总是会占主导地位形成主干。每个主干的长度在不同胚胎间有所差异，总是终止于一个由窦状内皮管组成的丛状结构。到第10天时，冠状动脉干更长，有许多主要分支。在组织学上，仍可见多条通道的迹象。值得注意的是，来自球部血管环的通道在主动脉窦的非常特定的点穿透主动脉，而不穿透肺动脉干或其他主动脉部位。我们认为这一事实表明，来自球部血管环的通道对主动脉窦的穿透代表了对主动脉的一种受控侵入。
