Pathophysiological investigation of cardiomyopathy in experimental studies using cardiomyopathic hamster(Bio14.6)

1)观察I-125 MIBG在心肌病仓鼠心肌摄取比的连续变化。注射后4小时心肌病仓鼠I-125 MIBG心肌冲蚀比对照组增加。心肌病仓鼠的特点是注射后1小时内I-125 MIBG快速冲洗。这些结果为评估肥厚性心肌病交感神经功能障碍的机制提供了有用的信息。2)研究了在给药和不给药的情况下，心肌病仓鼠（Bio14.6） I-125 BMIPP的心肌摄取率。两组间I-125 BMIPP的心肌摄取率无显著差异。3)应用Gd-C-14-DTPA对心肌病仓鼠（Bio14.6）心肌x线自显影进行组织病理学检查。随着年龄的增长，左心室肥大，重量增加，肉芽组织增生，组织学切片上毛细血管增生，间质纤维化增多。Gd-C-14-DTPA在纤维化组织中大量积聚。特别是Gd-C-14-DTPA在毛细血管增生和炎症细胞浸润较多、胶原纤维较少的组织中积累较多。4)心肌病仓鼠（Bio14.6）给予Gd-DTPA后，对切除的心脏进行MR成像。肥大左心室壁的MR图像在3个月大时显示均匀增强，在6个月大时变得不均匀，混合了显著增强和未增强的区域。在10-12个月大时，左心室的磁共振图像增强程度较低。5)心肌病仓鼠心肌H-1谱图（Bio14.6）。心肌病仓鼠的牛磺酸与磷酸肌酸比值明显高于正常叙利亚仓鼠。在心力衰竭阶段，肉碱与磷酸肌酐的比值降低。

1) Serial change of myocardial uptake ratio of I-125 MIBG was investigated in cardiomyopathic hamsters. Myocardial washout of I-125 MIBG was increased in cardiomyopathic hamsters than the controls 4 hours after injection. The cardiomyopathic hamster is characterized by rapid washout I-125 MIBG within 1 hour after injection. These results provided useful information in assessing the mechanism of sympathetic nerve dysfunction in hypertrophic cardiomyopathy.2) Myocardial uptake ratio of I-125 BMIPP was investigated in cardiomyopathic hamster (Bio14.6) with and without administration of Coenzyme Q10. There was no significant difference in myocardial uptake ratio of I-125 BMIPP between them.3) Histopathological examination of myocardial autoradiogram with Gd-C-14-DTPA in cardiomyopathic hamster (Bio14.6) was performed. As the age was older, the left ventricle became hypertrophied and increased in weight and granulation tissues with capillary proliferation and interstitial fibrosis increased on histological sections. Gd-C-14-DTPA showed much accumulation in the tissue with fibrosis. In particular, Gd-C-14-DTPA revealed higher accumulation in the tissues with much capillary proliferation and inflammatory cell infiltration and less collagen fibers.4) After administration of Gd-DTPA to cardiomyopathic hamster (Bio14.6), MR imaging of the excised hearts was performed. MR images of the hypertrophied left ventricular walls showed homogeneous enhancement at age of 3 months old and became inhomogeneous with mixture of strikingly enhanced and unenhanced areas at age of 6 months old. The left ventricle was less enhanced on MR images at age of 10-12 months old.5) Myocardial H-1 spectroscopy was obtained in cardiomyopathic hamster (Bio14.6). The ratio of taurine to phosphocreatimine was significantly higher in cardiomyopathic hamster than that of normal Syrian hamster. The ratio of carnitine to phosphocreatinine became lower at the stages of cardiac failure.