Kochova Petra, Tonar Zbynek, Matejka Vit M, Sviglerova Jitka, Stengl Milan, Kuncova Jitka
Department of Mechanics, Faculty of Applied Sciences, University of West Bohemia, Univerzitni 22, Pilsen, Czech Republic.
Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2008 Dec;152(2):239-45. doi: 10.5507/bp.2008.037.
This work focuses on the morphological and mechanical changes in the wall of the subrenal aorta in rats suffering from arterial hypertension and chronic renal failure induced by subtotal nephrectomy (NX).
The quantitative structural parameters were assessed using stereological methods. The mechanical properties were determined using uniaxial tensile tests.
Morphological results showed no significant differences in the wall structure of NX rats ten days following the subtotal nephrectomy in comparison with the control animals. Pronounced structural changes appeared ten weeks after the nephrectomy. The area of the profile of the arterial lumen, the volume fraction of elastin, and the elastin lamellar number in the tunica media were significantly higher in the NX rats than in the control animals. The values of the volume fraction of the smooth muscle cells in the tunica media and the lamellar unit thickness were significantly lower for the NX animals. Mechanical results showed that both kinds of tissues were characterized by a non-linear response when subjected to the tensile test. The moduli of elasticity of subrenal aortas in control and NX animals were different only for large deformations: NX samples had higher stiffness. The cyclic loading resulted in a time-dependent response for both tissue types.
The results obtained from the NX rats ten days as well as ten weeks after operation suggested an outward hypertrophy of the aorta. The subrenal aortas of the NX animals had less strength and were less extensible than those of the control animals.
本研究聚焦于因肾大部切除（NX）诱导的动脉高血压和慢性肾衰竭大鼠肾下腹主动脉壁的形态学和力学变化。
使用体视学方法评估定量结构参数。通过单轴拉伸试验测定力学性能。
形态学结果显示，与对照动物相比，肾大部切除术后10天的NX大鼠的主动脉壁结构无显著差异。肾切除术后10周出现明显的结构变化。NX大鼠动脉腔轮廓面积、弹性蛋白体积分数和中膜弹性蛋白层数均显著高于对照动物。NX动物中膜平滑肌细胞体积分数值和板层单位厚度显著更低。力学结果表明，两种组织在拉伸试验中均表现出非线性响应。对照动物和NX动物肾下腹主动脉的弹性模量仅在大变形时有所不同：NX样本具有更高的刚度。循环加载导致两种组织类型均出现时间依赖性响应。
术后10天和10周从NX大鼠获得的结果表明主动脉向外肥大。NX动物的肾下腹主动脉比对照动物的强度更低且伸展性更差。
