動・静脈平滑筋の比較研究と Atherogenesis

Collagen Phenotype の産生と分布

抄録

Biochemical, ultrastructural and immunohistochemical studies on collagen of the human aortic media and vena cava were performed. Biochemical analysis revealed that the aortic media consisted of 55% type I and 45% type III collagen. On the other hand, the collagen composition of the vena cava was further distinguishable form that of the aortic media by a high content of type I collagen (75%). In an ultrastructural study of collagen fibrils, the aortic media contained two distinct groups of collagen fibrils; small and large fibrils measuring 260±20Å and 440±40Å in diameter respectively. The vena cava also exhibited small (360±40Å) and large (560±40Å) groups of collagen fibrils, and the latter predominated in amount. However, the diameter of each groups of the fibrils of the vena cava was always larger than that of the aortic media. These findings presumably ensued the following results; the small collagen fibril, which was fairly less in amount in the vena cava, was made up of type III collagen molecules, and the large one was of type I collagen molecules. The difference of the diameter of collagen fibrils between the aortic media and the vena cava indicated that the diameter of collagen fibrils should be related to the circumstances in which collagen was synthesized. Immunohistochemically, the predominance of type III collagen in the intima and media of the aorta was, at this time, a matter of speculation.