Shatari T, Teramoto T, Kitajima M, Minamitani H
Department of Surgery, School of Medicine, Keio University, Tokyo, Japan.
Surg Today. 1995;25(3):233-6. doi: 10.1007/BF00311533.
To re-establish anal function in fecally incontinent patients it may be feasible to transpose the gracilis muscle around the anal canal, using electrical stimulation to trigger contraction. However, because the fast-twitching gracilis muscle is incapable of prolonged contraction without fatigue, it is necessary to convert it to a slow-twitching, fatigue-resistant muscle. We demonstrated this conversion by longterm electrical stimulation at low frequencies using a rabbit model. The nerve to the gracilis muscle was continuously stimulated at 2 Hz, 5 Hz, and 10 Hz for 2, 4, or 6 weeks. In the 6-week conditioning group, the percentage of type I fibers, identified by ATPase staining, increased as the conditioning frequency became higher, but the twitch contraction speed reduced with conditioning at a frequency of more than 5 Hz. The fatigue resistance improved by conditioning at 10 Hz, and conversion occurred in 6 weeks. Thus, we concluded that conditioning at 10 Hz for 6 weeks can convert rabbit gracilis muscle to a slow-twitching, fatigue-resistant muscle suitable for use as a neoanal sphincter.
对于大便失禁患者，将股薄肌围绕肛管移位，并利用电刺激触发收缩，可能有助于重建肛门功能。然而，由于快速抽搐的股薄肌在不疲劳的情况下无法长时间收缩，因此有必要将其转变为慢速抽搐、抗疲劳的肌肉。我们使用兔模型通过低频长期电刺激证明了这种转变。以2赫兹、5赫兹和10赫兹的频率对股薄肌神经连续刺激2周、4周或6周。在6周的条件训练组中，通过ATP酶染色鉴定的I型纤维百分比随着条件训练频率的升高而增加，但在频率超过5赫兹的条件训练下，抽搐收缩速度降低。10赫兹的条件训练提高了抗疲劳能力，且在6周内发生了转变。因此，我们得出结论，以10赫兹的频率进行6周的条件训练可以将兔股薄肌转变为适合用作新肛门括约肌的慢速抽搐、抗疲劳肌肉。
