New method for the analysis of motor function on experimental animals.

建立了一种新的可定量检测实验动物运动功能的改良方法。该方法基于对电诱发肌肉收缩和肌电的计算机分析，在乌拉坦麻醉条件下测定了代偿性肥厚大鼠模型和老年(2岁以上)大鼠的收缩特性和肌电，并与对照组进行了比较。代偿性肥厚肌(CHM)的抽搐和破伤风较对照肌慢，组织化学分析支持这一趋势。然而，CHM的抗疲劳能力却不合理地低于对照肌肉。同时，我发现CHM与大量复杂分支纤维(CBF)的出现有关。我还证实，在肌营养不良小鼠的肌肉中也观察到了CBF(MDX：Tamaki等人，Anat.Rec.1993)，并在反复被布比卡因改变的肌肉中观察到CBF(Tamaki和Akatsuka，Anat.Rec.1994)。因此，有可能CBF的存在可能干扰了整个肌肉的组织化学和功能特性之间的相关性。老年大鼠的抽搐和破伤风反应也慢于对照组。对照组大鼠在100赫兹的刺激频率下均可获得完全破伤风。然而，一些老年大鼠不能接受超过50赫兹的刺激。这表明，考虑衰老对运动功能的影响是非常重要和有趣的事实。综上所述，这种新改进的实验动物运动功能分析方法对量化各种实验动物的运动功能是有用的。

Newly modified method that could be quantitative the motor function on laboratory animals was established. This method is based on the computer analysis for electrically evoked muscle contractions and EMG.Contractile properties and EMG of the compensatory hypertrophied rat model and senile (over 2 year-old) rats were measured under urethane anesthetized condition, and compared with those of control rats. Twitch and tetanus of compensatory hypertrophied muscle (CHM) were slower than control muscle, and this tendency was supported by the histochemical analysis. However, the fatigue resistance capacity of CHM was illogically less than that of control muscles. At the same time, I found that CHM was associated with the appearance of numerous complex branched fibers (CBF). I also confirmed that CBF was also observed in the muscles of muscular dystrophy mouse (mdx : Tamaki et al., Anat.Rec.1993) and in the muscles repeatedly altered by bupivacaine hydrochloride (Tamaki and Akatsuka, Anat.Rec.1994). Thus, possibility is suggest that the presence of CBF may disturb the correlation between histochemical and functional properties of the whole muscle. In the senile rats, properties of twitch and tetanus were also slower than control rats. In the control rats, complete tetanus could be always obtained at 100Hz of stimulation frequency. However, some of senile rats could not follow over 50Hz stimulation. It is suggest that this is very important and interesting fact to consider the effects of aging for motor function. In conclusion, this "Newly modified method for the analysis of motor function on laboratory animals" is useful to quantitative the motor function of various laboratory animals.