Carlson B M, Faulkner J A
Department of Anatomy and Cell Biology, University of Michigan, Ann Arbor, USA.
J Gerontol A Biol Sci Med Sci. 1998 Jan;53(1):B52-7. doi: 10.1093/gerona/53a.1.b52.
We tested the hypothesis that after skeletal muscle regeneration in old compared with young rats damage to the motor nerve rather than damage to muscle fibers determines the magnitude of the deficits in muscle mass and maximum force (Po). The mass and Po of extensor digitorum longus (EDL) muscles of young (4 months) and old (24 months) male rats were compared two months following (i) Marcaine treatment plus simultaneous motor nerve transection, (ii) motor nerve transection alone, and (iii) Marcaine treatment alone (from data compiled previously). In both the nerve transection-only and Marcaine with nerve transection groups the recovery of mass and Po was significantly greater in young than in old rats. This is in contrast to our previous data showing that in the absence of nerve damage Marcaine-treated muscle in old rats regenerates as well as that in young rats. Our hypothesis was supported, and we conclude that impaired axonal regeneration, re-establishment of nerve-muscle contact, or both, is the critical component in the impaired regeneration of muscle grafts in old as compared with young rats.
与年轻大鼠相比，在老年大鼠骨骼肌再生后，运动神经损伤而非肌纤维损伤决定了肌肉质量和最大力量（Po）的缺失程度。在（i）布比卡因治疗加同时进行运动神经横断、（ii）仅进行运动神经横断、（iii）仅进行布比卡因治疗（数据来自之前汇总）两个月后，比较了年轻（4个月）和老年（24个月）雄性大鼠的趾长伸肌（EDL）的质量和Po。在仅进行神经横断组和布比卡因加神经横断组中，年轻大鼠的质量和Po恢复均显著大于老年大鼠。这与我们之前的数据形成对比，之前的数据显示，在没有神经损伤的情况下，老年大鼠经布比卡因治疗的肌肉与年轻大鼠的肌肉再生情况相同。我们的假设得到了支持，并且我们得出结论，与年轻大鼠相比，轴突再生受损、神经 - 肌肉接触的重新建立或两者皆是老年大鼠肌肉移植再生受损的关键因素。
