Abstract: Objective To compare the the structure and aerobic power of skeletal muscle between the naked mole rat and C57BL/6J mice. Method The musculus gastrocnemius were isolated from anaesthetic animals and made to paraffin sections and frozen section. The microstructure and ultrastructure of skeletal muscles were observed under optical microscope and transmission electron microscope. Meanwhile, the skeletal muscles were immuohistochemical stainined with CD34 antibody, which revealed the microvessel density in skeletal muscles. At last, myoglobin in skeletal muscles were measured by spectrophotometry. Result Comparasion with C57BL/6J mice ,the skeletal muscle fibrils of NMR are larger, and connective tissuse are more abundant; The number of mitochondrial in NMR is larger, but the volume of mitochondrial is smaller; The microvessel density of NMR skeletal muscle both is much higher; and the myoglobin is 1.5 times higher. Conclusion NMR is more muscular then C57BL/6J mice, and rich in connection tissuse ,which lead skeletal muscle to be more softer and more flexible then C57BL/6J mice. The most importantly, NMR has much more amount mitochondrial, microvessel and myoglobin,which revealed that the aerobic power of NMR skeletal muscle is stronger then C57BL/6J mice.

Key words: Naked mole rat, Skeletal muscle, Structure, Microvessel, Myoglobin, Aerobic power