JaLCDOI 10.18926/15177
Title Alternative Development of intramuscular probe for local muscle function
FullText URL 016_1_001_008.pdf
Author Oka, Hisao| Edamatsu, Motonari| Watanabe, Shogo| Kitawaki, Tomoki|
Abstract 臨床においては,筋機能や機能不全を診断するために,表面筋電図や針筋電図,筋生検などが行われている。しかし,これらの方法では筋機能や筋収縮メカニズムを連続的に測定することは難しい。本研究では新たに筋内挿入型プローブと測定システムを開発した。測定プローブは光ファイバと6本の白金細線から構成されている。光ファイバを用いて筋の局所血流量と筋内圧力を測定し,6個の電極を用いて運動単位活動電位を測定した。プローブと測定システムの基礎特性を確認した後,麻酔下のラットの排腹筋において,安静時および局所虚血時の活動電位,血流量,筋内圧力を測定した。また脛骨神経を電気刺激し,活動電位波形から伝播速度を算出したところ,プローブは正常に動作していることが確認できた。さらに筋小胞体からのカルシウム放出チャネルを抑制するdantroleneを筋注すると,筋内圧力波形は大きく減少したが,活動電位波形はほとんど変化しないことがわかった。
Abstract Alternative In order to diagnose muscle function or dysfunction, surface/needle electromyograms, muscle biopsy, biochemical markers inspection, muscle tone, etc. are carried out. It is difficult to measure muscle function continuously by using these methods. In this study, an intramuscular probe and measurement system were developed. The probe is composed of optical fibers and six small platinum electrodes. The probe, the tip of which is protected by epoxy resin, is inserted in a cannula of 1.26mm in diameter. By using the fibers, the local blood flow in a muscle and the intramuscular pressure were measured. By using six electrodes (50μm in diameter), a motor unit action potential was measured. The time-course changes of the action potential, blood flow and intramuscular pressure were measured in the gastrocnemius muscle of rats under the resting and the local ischemia. The tibial nerve was stimulated electrically using the current of the unipolar and negative polarity with 50μs pulse duration every 2 seconds and the propagation velocity of the action potential was calculated from the potential waves. The animal tests using rats were carried out in order to verify the developed probe and system. Under the local ischemia, the action potential, the blood flow and the intramuscular pressure decreased and the propagation velocity became slower. When dantrolene sodium was injected, which inhibits the calcium release channel of the sarcoplasmic reticulum, the intramuscular pressure decreased but the action potential wave was still detectable.
Keywords 筋機能 (muscle function) 筋内圧力 (intramuscular pressure) 筋内血流 (intramuscular blood flow) 活動電位 (action potential) 筋収縮 (muscle contraction)
Publication Title 岡山大学医学部保健学科紀要
Published Date 2005-12-25
Volume volume16
Issue issue1
Start Page 1
End Page 8
ISSN 1345-0948
language 日本語
File Version publisher
NAID 120002307295