【摘要 】 目的 探讨压力负荷增高性心肌肥厚大鼠心肌胶原网络的重塑及其与内皮素(ET)的可能关系。方法 腹主动脉部分结扎致大鼠心肌肥厚,VG染色和图像处理观察心肌胶原网络重塑,放免测定心肌局部ET-1含量,³ H-胸腺嘧啶(³ H-TdR)和³ H-脯氨酸参入试验观察心肌成纤维细胞的分裂增殖和胶原合成。结果 手术组大鼠术后2周即出现明显左室肥厚,其程度随时间进展而加重。与假手术组比较，左室心肌总胶原容积百分比(CVF-T)于术后2周增高,术后4、8周CVF-T和无小血管视野CVF(CVF-NV)均明显增高(P<0.01)。手术组大鼠左室心肌局部ET-1含量明显高于相应假手术大鼠(P<0.01),且10^-12 ～10^-8 M浓度的ET-1对培养心肌成纤维细胞³ H-TdR和³ H-脯氨酸的参入量有明显刺激作用,呈剂量依赖性。结论 压力负荷增高性心肌肥厚形成过程中伴有心肌胶原网络重塑,心肌局部ET-1含量增加可能与心肌胶原网络重构的形成有一定关系。

Wang Changqian, Liu Mingyuan, Huang Dingjiu, et al. Renji Hospital, Shanghai Second Medical University, Shanghai 200001

【Abstract 】 Objectives To examine myocardial collagen network remodeling and its possiblerelation with endothelin (ET ) in rats with pressure-overloaded hypertrophic myocardium. Methods Abdominal aorta banding was used to induce myocardialhypertrophy in rats. Myocardial collagen was stained with VG and analyzed using a computerassisted procedure. Myocardium ET -1 concentration was measured by RIA. The synthesis ofDNA and collagen in cultured cardiac fibroblasts were assessed by incorporation of ³ H-TdRand ³ H-proline.Results The operated rats manifested myocardial hypertrophy after 2 weeksof operation. As time advancing, the degree of myocardial hypertrophy became heavier. Incomparison to sham-operated rats, myocardial total-collagen volume fraction (CVF-T)increased after 2 weeks of operation (P<0.05), CVF-T and nonvascular -collagen volumefraction (CVF-NV) both increased significantly after 4 and 8 weeks of operation(P<0.01). In operated rats, ET-1 content of left ventricular myocardium wassignificantly higher than that of sham-operated rats (P<0.01). 10^-12 -10^-8 mol/L ET-1 could enhance the incorporationrate of ³ H-TdR and ³ H-proline in a dose-dependent manner in culturedcardiac fibroblasts.Conclusion Myocardial collagen network remodeling occurs during thedevelopment of pressure-overloaded hypertrophic myocardium. The increase of local ET-1content is probably related to the formation of myocardial collagen network remodeling.

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