Maxwell L C, Barclay J K, Mohrman D E, Faulkner J A
Am J Physiol. 1977 Jul;233(1):C14-8. doi: 10.1152/ajpcell.1977.233.1.C14.
Our purpose was to determine if physiological characteristics of skeletal muscles of dogs and cats are related to their histochemical and biochemical characteristics. Maximum oxygen consumption (VO2max) and blood flow (Q) at VO2max were determined for in situ muscles of dogs and cats. Compared to cat muscles, dog muscles per unit mass had higher succinate oxidase activities, VO2max's, and Q's at VO2max's. There are positive relationships between Q at VO2max and VO2max and between VO2max and succinate oxidase activity. The higher VO2max's and succinate oxidase activities of dog muscles are consistent with the presence in these muscles of only slow-twitch fatique-resistant fibers and fast-twitch fatique-resistant fibers, whereas up to 50% of the fibers found in cat muscles are fast-twitch fatiqable. Capillary-to-fiber ratios are 2.40-2.97 for dog muscles compared to 2.17-2.84 for cat muscles. Thus the two- to threefold higher Q at VO2max for dog muscles compared to cat muscles is not due to a greater number of capillaries.
我们的目的是确定狗和猫骨骼肌的生理特征是否与其组织化学和生化特征相关。测定了狗和猫原位肌肉的最大耗氧量（VO2max）以及VO2max时的血流量（Q）。与猫的肌肉相比，狗的肌肉每单位质量在VO2max时具有更高的琥珀酸氧化酶活性、VO2max值和Q值。VO2max时的Q与VO2max之间以及VO2max与琥珀酸氧化酶活性之间存在正相关关系。狗肌肉较高的VO2max值和琥珀酸氧化酶活性与这些肌肉中仅存在慢肌抗疲劳纤维和快肌抗疲劳纤维一致，而在猫肌肉中发现高达50%的纤维是快肌易疲劳纤维。狗肌肉的毛细血管与纤维比例为2.40 - 2.97，而猫肌肉为2.17 - 2.84。因此，与猫肌肉相比，狗肌肉在VO2max时的Q值高出两到三倍并非由于毛细血管数量更多。
