Study on Cardiac Abnormality in hamster model of hereditary cardiomyopathy

遗传性心肌病仓鼠模型心脏异常的研究

• 批准号: 05670645
• 负责人: SHIGEKAWA Munekazu
• 金额: $ 1.34万
• 依托单位: National Cardiovascular Center Research Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05670645/
• 关键词: Cardiomyopathy; Cardiomyopathic hamster; Dystrophin; Dystrophin-associated glycoprotein; Cytoskeleton; ハムスター; ジストロフィン結合蛋白質

1) In the ventricular muscle from 30-to 40-day-old Bio14.6 cardiomyopathic hamsters, the concentration of dystrophin was about 50% less than the normal controls. Despite its reduced content, extraction of dystrophin from the myopathic muscle into the microsomal fraction was threefold higher as compared to the control. These results suggest that abnormality exists in the association of dystrophin with sarcolemmal membranes in the myopathic muscle. No obvious difference, however, observed between normal and myopathic myocytes in their immunocytochemical staining patterns.2) In ventricular muscle from 30-to 60-day-old cardiomyopathic hamsters, dystrophin-associated glycoproteins of 43,50 and 150 kDa are markedly reduced in abundance. In particular the 50 kDa glycoprotein is totally deficient in the sarcolemma of myopathic ventricular myocytes as revealed by immunofluorescence microscopy. The dystrophin-glycoprotein complex formation is defective in the cardiomyopathic hamster heart, becau … More se dystrophin and glycoprotein behave independently when digitonin-solubilized ventricular homogenates are fractionated on wheat germ agglutinin beads or antidystrophin immunoaffinity beads.3) Dystrophin-dystrophin associated protein complex was isolated from digitonin-solubilized normal hamster cardiac muscle by a two-step method involving succinylated wheat germ agglutinin beads and anti-dystrophin antibody beads. While protein composition of the cardiac dystrophin associated protein complex was not differnt from that of the skeletal muscle counterpart, the protein yield of the cardiac complex was approximately 10 times as great. Unlike the skeletal complex, the cardiac complex could not be soulbilized from a microsomal fraction with 1% digitonin. These results indicates the difference in the property and content of cardiac versus skeltal dystrophin complex, suggesting a unique role for this protein complex in the cardiac muscle function.4) We have investigated the distribution of the sarcolemmal Ca^<2+> transporters in hamster and dog ventricular myocytes by immunocytochemical and membrane fractionation techniques. The data suggest that the DHP receptor alpha1 subunit and the Na^+/Ca^<2+> exchanger are present in surface sarcolemma as well as T-tubule membranes located at the cardiac dyads. Compared with these Ca^<2+> transporters, the sarcolemmal Ca^<2+>-ATPase is much less abundant in the latter fraction. Thus the sarcolemmal Ca^<2+>-ATPase seems to be located predominantly in surface sarcolemma. Less

1)在30至40日龄Bio14.6心肌病仓鼠的心室肌中，肌营养不良蛋白的浓度比正常对照低约50%。尽管其含量减少，提取肌营养不良蛋白从肌病肌肉到微粒体部分是三倍高，相比于对照。这些结果表明，异常存在的协会肌营养不良蛋白与肌纤维膜在肌病肌肉。2）在30 ~ 60日龄心肌病仓鼠心室肌中，抗肌萎缩蛋白相关糖蛋白43、50和150 kDa的丰度明显减少。特别是50 kDa的糖蛋白是完全缺乏肌病心室肌细胞的肌膜，如免疫荧光显微镜所示。心肌病仓鼠心脏中肌营养不良蛋白-糖蛋白复合物的形成是有缺陷的，因为 ...更多信息 当毛地黄皂苷溶解的心室匀浆在麦胚凝集素珠或抗肌养蛋白免疫亲和珠上分级分离时，肌养蛋白和糖蛋白独立地表现。3）通过包括琥珀酰化麦胚凝集素珠和抗肌养蛋白抗体珠的两步法从毛地黄皂苷溶解的正常仓鼠心肌分离肌养蛋白-肌养蛋白相关蛋白复合物。虽然心脏肌营养不良蛋白相关蛋白复合物的蛋白质组成与骨骼肌对应物的蛋白质组成没有差异，但心脏复合物的蛋白质产量约为骨骼肌对应物的10倍。与骨骼复合物不同，心脏复合物不能从含有1%毛地黄皂苷的微粒体组分中被soulbilized。这些结果表明，心肌与心室肌抗肌萎缩蛋白复合物在性质和含量上存在差异，提示这种蛋白复合物在心肌功能中具有独特的作用。4）我们用免疫细胞化学和膜分离技术研究了肌膜Ca^2+转运蛋白在仓鼠和狗心室肌细胞中的分布。这些数据表明，DHP受体α 1亚单位和Na^+/Ca^2+交换蛋白存在于心脏二分体的表面肌膜和T-小管膜中。与这些Ca^<2+>转运体相比，肌膜Ca^<2+>-ATP酶在后一部分中的含量要少得多。因此，肌膜Ca^2+-ATP酶似乎主要位于肌膜表面。少

项目成果

Iwata,Y.: "Defective association of dystrophin with Sarcokemmal glycoproteins in the cardiomyopathic hamster heart." FEBS Lett.329. 227-231 (1993)

Iwata，Y.：“肌营养不良蛋白与心肌病仓鼠心脏中的肌瘤糖蛋白的缺陷关联。”

Iwata,Y.: "Altered membrane-dystrophin association in the cardiomyopathic hamster heart muscle." Biochim.Biophys.Res.Commun.190. 589-595 (1993)

Iwata,Y.：“心肌病仓鼠心肌中膜-肌营养不良蛋白关联的改变。”

岩田裕子 ら: "Increased mechanical extraction of T-tubule/junctional SR from cardiomyopathic hamster heart" Am.J.Physiol.264. H1447-H1453 (1993)

Yuko Iwata 等人：“从心肌病仓鼠心脏中增加 T 管/连接 SR 的机械提取”Am.J.Physiol.264 (1993)。

Tawada-Iwata,Y.: "Increased mechanical extraction of T-tubule/junctional SR from cardio myopathic heart." Am.J.Physiol.264. H1447-H1453 (1993)

Tawada-Iwata,Y.：“增加从心肌病心脏中机械提取 T 型小管/连接 SR。”

Iwata, Y., Hanada, H., Takahashi, M., Shigekawa, M.: "Ca^<2+>-ATPase distributes distributes differently in cardiac sarcolemma than dihydropyridine receptor alpha1 subunit and Na^+/Ca^<2+> exchanger." FEBS Lett.355. 65-68 (1994)

Iwata, Y.、Hanada, H.、Takahashi, M.、Shigekawa, M.：“Ca^2-ATPase 在心脏肌膜中的分布与二氢吡啶受体 α1 亚基和 Na^/Ca^2 交换器不同。