Molecular biological changes of ADP/ATP carrier protein in cardiomyopathic hamsters

ATP/ADP载体蛋白（AAC）是存在于线粒体内膜内的一种完整蛋白，负责细胞质和线粒体内ADP和ATP的交换。研究了J-2-N型心肌病仓鼠、肾血管性高血压大鼠和糖尿病大鼠心肌ACC含量的变化。心肌病仓鼠ACC蛋白含量明显降低。另一方面，心肌病仓鼠ACC m-RNA水平升高。肾血管性高血压大鼠（2K-1C）术后8周左室肥厚，肌球蛋白同工酶谱异常。术后大鼠ACC蛋白含量明显降低。链脲佐菌素诱导的糖尿病大鼠ACC蛋白含量明显升高。提示AAC蛋白的改变在心肌病、肥厚和糖尿病心脏血流动力学改变的发病机制中起重要作用。此外，这些变化被认为是一种适应，有助于在几种心脏疾病中在低氧和低能量利用的情况下保持有效的力量发展。

The ATP/ADP carrier protein (AAC) is an integral protein present in the inner mitochondrial membrane that performs the exchange of cytoplasmic and intramitochondrial ADP and ATP.The ACC content of the myocardium was studied in J-2-N cardiomyopathic hamster, renovascular hypertensive rats and diabetic rats.The content of ACC protein was significantly decreased in cardiomyopathic hamster. On the other hand, ACC m-RNA level was increased in cardiomyopathic hamster. In renovascular hypertensive rat (2K-1C), left ventricular hypertrophy and abnormal changes of myosin isoenzyme pattern were observed 8 weeks after an operation. The content of ACC protein was significantly decreased in operated rats. In streptozotocin-induced diabetic rats, the content of ACC protein was significantly increased.These results suggest that the changes of the AAC protein play an important role in the pathogenesis of hemodynamic alteration of cardiomyopathy, hypertrophy and diabetic hearts. Moreover, these changes were considered to be an adaptation which contribute to maintain efficient force development with low oxygen and energy utilization in several cardiac deceases.