大動脈瘤破裂診断システムの開発と破裂予防に関する実験的研究

主动脉瘤破裂诊断系统研制及破裂预防实验研究

• 批准号: 11470267
• 负责人: TABAYASHI Koichi
• 金额: $ 5.5万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11470267/
• 关键词: Elastase-induced rat aneurysmal model; pipette aspiration; local wall elastic modulus; Intravascular ultrasound system; Wall motion; Matrix metalloproteinases (MMPs); elastase-induced aneurysm model; Matrix metalloproteinase(MMP); rat大動脈瘤モデル; 血管内

Introduction : The first objective of this study is to develop the methodology to estimate aortic aneurysm biomechanically. The second objective is to estimate a significance of matrix metalloproteinase (MMP) compared with biomechanical stress.Methods : We used the elastase-induced rat aneurysmal model. 1) Measurement of the aneurysmal wall motion and geometry by intravascular ultrasound system. 2) Measurement of the wall stiffness by the pipette aspiration. 3) Histological analysis. 4) Measurement of the MMP activity by gelatin zymography.Results : Intra-aortic infusion of elastase produced significant aortic dilatation (control, 1.7±0.26mm, ; 7days, 5.46±1.38 mm ; 14days, 6.46±1.45 mm). No cases ruptured, but the daughter aneurysms were produced in a few cases. Aneurysmal wall motion significant decreased. Most aneurysm lumens contained mural thrombus. The elastic modulus of the maximal dilated position decreased once, and increased significantly. The excessive fibrosis occurred in adventitia of aneurysmal wall. The neutrophils mural infiltration occurred early time. MMP-2 activities increased in aneurysmal wall, but not MMP-9.Conclusions : In this model, instability of aneurysmal wall occur in maximal dilated position at first, and the area move to distal midsection. The balance of wall stress and wall strength is important to aneurysmal dilatation and rupture. MMP-2 needs to vascular remodeling. MMP-9 will destroy wall structure in this model.

简介：这项研究的第一个目的是开发方法来估计主动脉瘤生物力学。第二个目标是估计基质金属蛋白酶（MMP）与生物力学应力相比的重要性。方法：我们使用了弹性酶诱导的大鼠动脉瘤模型。 1）通过血管内超声系统测量动脉瘤壁运动和几何形状。 2）通过移液器抽吸测量壁刚度。 3）组织学分析。 4）通过明胶酶学对MMP活性的测量：弹性酶内部输注弹性酶会产生明显的主动脉扩张（对照，1.7±0.26mm； 7days，5.46±1.38mm; 14days; 14d日，6.46±1.45mm）。没有病例破裂，但是在少数情况下产生了女儿动脉瘤。动脉瘤的大幅下降。大多数动脉瘤腔都包含壁球。最大扩张位置的弹性模量降低了一次，并显着增加。过量的纤维化发生在动脉瘤壁之前。中性粒细胞浸润发生了早期。 MMP-2活性在动脉瘤壁中增加，但不是MMP-.9。结论：在此模型中，动脉瘤壁的不稳定性首先在最大的扩张位置发生，而该区域移至远端中心。壁应力和壁强度的平衡对于动脉瘤扩张和破裂很重要。 MMP-2需要进行血管重塑。 MMP-9将在此模型中破坏墙壁结构。