Endo H, Maeda S, Kimura J, Yamada J, Rerkamnuaychoke W, Kurohmaru M, Hayashi Y, Nishida T
Department of Zoology, National Science Museum, Tokyo, Japan.
J Vet Med Sci. 1995 Jun;57(3):389-93. doi: 10.1292/jvms.57.389.
Cardiac myocytes in the left ventricle and atrium of the greater bandicoot rat (Bandicota indica) were examined by transmission electron microscopy. The fine structure showed typical features of mammalian cardiac myocytes. In atrial myocytes, however, the areas occupied by mitochondria were much smaller than that filled with myofibrils. The decrease in mitochondria and the abundance of myofibrils are thought to be an ultrastructural adaptation to the large body size of this species. Many conducting myocytes were observed in both atrium and ventricle. The atrial conducting myocytes were ultrastructurally different from the Purkinje fibers of the ventricle. We suggest that the abundance and the ultrastructural variation of conducting myocytes are related to the physiological aspects, such as body size, of this animal.
通过透射电子显微镜对大袋狸（印度袋狸）左心室和心房的心肌细胞进行了检查。其精细结构显示出哺乳动物心肌细胞的典型特征。然而，在心房肌细胞中，线粒体占据的区域比充满肌原纤维的区域小得多。线粒体的减少和肌原纤维的丰富被认为是该物种体型巨大的一种超微结构适应。在心房和心室中均观察到许多传导性心肌细胞。心房传导性心肌细胞在超微结构上与心室的浦肯野纤维不同。我们认为传导性心肌细胞的丰富性和超微结构变化与该动物的生理方面，如体型大小有关。
