Response of the Rat Aortic Media to Hypertension: Morphological and Chemical Studies
Response of the Rat Aortic Media to Hypertension: Morphological and Chemical Studies
复制标题
大鼠主动脉中层对高血压的反应：形态学和化学研究
作者：
H. Wolinsky
临床和实验研究表明，高血压加速了动脉硬化的发展。对扩张的大鼠胸主动脉进行了形态和化学研究，以确定伴随高血压而来的中层结构和成分的变化，并将这些变化与计算的中层应力的增加联系起来。与正常血压动物相比，8周的高血压患者胸主动脉中层的内径、中层厚度和横截面积显著增大。高血压动物的内侧板层单位的计算张力显著高于正常血压动物，但内侧板层单位的数量并不比正常血压动物的正常数多；这导致高血压动物的主动脉每内侧板层单位的计算张力的值显著升高。同一节段中膜横截面积与总张力之间存在高度显著的线性关系。此外，高血压动物的中膜弹性蛋白和胶原的绝对量都增加了；然而，这些成分的百分比基本保持不变，表明主动脉组织的组成几乎没有变化。这两种纤维蛋白的增加与计算的壁应力的增加呈线性相关，弹性蛋白和胶原的中间积累以相似的速度进行。这些发现表明血管大小、中层弹性蛋白和胶原蛋白的数量与计算的壁张力之间存在线性关系。
Clinical and experimental studies indicate that hypertension accelerates the development of arteriosclerosis. Morphological and chemical studies of the distended rat thoracic aorta were undertaken to define the structural and compositional alterations of the media which accompany hypertension and to relate these changes to increases in calculated medial stress. An 8-week period of hypertension was associated with significantly greater diameter, medial thickness, and cross-sectional area of the media of the thoracic aorta than in normotensive animals. Calculated wall tension was significantly higher in hypertensive animals, but the number of medial lamellar units was not greater than that usual in normotensive animals; this resulted in a strikingly elevated value for calculated tension per medial lamellar unit for the aortas of hypertensive animals. A highly significant linear relation was found between total tension and cross-sectional area of the media of the same segment. In addition, the absolute amounts of both medial elastin and collagen were increased in hypertensive animals; however, the percent of these elements remained essentially constant, indicating little change in the composition of aortic tissue. Increments in both fibrous proteins were linearly related to increases in calculated mural stress, and medial accumulations of elastin and collagen proceeded at similar rates. These findings demonstrate a linear relation among vessel dimensions and amounts of medial elastin and collagen and calculated wall tension.