Pynadath T I, Mukherjee D P
Atherosclerosis. 1977 Mar;26(3):311-8. doi: 10.1016/0021-9150(77)90083-1.
The effect of cholesterol and cholesterol ester content of aortas on the dynamic mechanical properties of these tissues was studied in rabbits during development of atherosclerosis. The disease was induced by feeding a 1.5% cholesterol diet for six weeks. At two week intervals, an equal number of control and experimental animals were sacrificed and their aortas were collected. After grading the aortas for lesions, one-half of each aorta was used for the determination of cholesterol and cholesterol ester content while the other half was used for the determination of viscoelastic properties. The viscoelastic properties were determined in both the longitudinal and the tangentail direction of the aortas. The results showed that cholesterol feeding had no effect on the longitudinal dynamic Young's modulus of the aortas. On the other hand, the tangential dynamic Young's modulus of the aortas was found to be very much influenced by the cholesterol diet. After the first two weeks of cholesterol feeding, the tangential dynamic Young's modulus was found to be increased markedly with time. At the end of the 6-week period, the average value of the tangential Young's moduli was 4.0 X 10(6) dynes/cm2 in the cholesterol-fed group while in the control group it remained 2.7 X 10(6) dynes/cm2. This increase in the tangential Young's moduli showed a remarkable correlation with the increase in the cholesterol ester content of the aortas. The cholesterol est content of aortas, like the tangential Young's modulus, remained unaffected during the first two weeks of cholesterol feeding. But after the first two weeks, a rapid increase in the cholesterol ester content was observed which coincided with an almost identical increase in the tangential Young's modulus values. It is concluded that during the early stages of atherosclerosis, the cholesterol ester content of aortas exerts a significant influence on the tangential dynamic Young's modulus of aortas. The serum levels of cholesterol and cholesterol ester, although increased steadily with the cholesterol feeding, did not show any direct correlation with the viscoelastic properties of the aortas.
在动脉粥样硬化发展过程中，研究了兔主动脉中胆固醇和胆固醇酯含量对这些组织动态力学性能的影响。通过喂食1.5%胆固醇饮食六周诱导疾病。每隔两周，处死等量的对照和实验动物并收集其主动脉。对主动脉病变分级后，每个主动脉的一半用于测定胆固醇和胆固醇酯含量，另一半用于测定粘弹性特性。在主动脉的纵向和切向方向测定粘弹性特性。结果表明，喂食胆固醇对主动脉的纵向动态杨氏模量没有影响。另一方面，发现主动脉的切向动态杨氏模量受胆固醇饮食的影响很大。喂食胆固醇的前两周后，发现切向动态杨氏模量随时间显著增加。在6周结束时，胆固醇喂养组的切向杨氏模量平均值为4.0×10(6)达因/平方厘米，而对照组仍为2.7×10(6)达因/平方厘米。切向杨氏模量的这种增加与主动脉中胆固醇酯含量的增加显著相关。主动脉的胆固醇酯含量，与切向杨氏模量一样，在喂食胆固醇的前两周内不受影响。但在两周后，观察到胆固醇酯含量迅速增加，这与切向杨氏模量值几乎相同的增加相吻合。得出结论，在动脉粥样硬化的早期阶段，主动脉的胆固醇酯含量对主动脉的切向动态杨氏模量有显著影响。血清胆固醇和胆固醇酯水平虽然随着喂食胆固醇而稳步升高，但与主动脉的粘弹性特性没有任何直接相关性。
