グリセリネートされた骨格とスムーズな筋肉:カルシウムとマグネシウムの依存性
Science (New York, N.Y.)
|March 26, 1965
まとめ
骨格筋と滑らかな筋肉の収縮は,カルシウムに依存していますが,マグネシウムの需要は異なります. 滑らかな筋肉は,類似のカルシウム値にもかかわらず,収縮のために骨格筋よりも10倍のマグネシウムを必要とします.
科学分野:
- 筋肉生理学 筋肉生理学
- バイオケミストリー バイオケミストリー
背景:
- 筋肉の収縮は基本的な生物学的プロセスです.
- 骨格筋と滑らかな筋肉は,異なる生理学的特徴を示しています.
- カルシウムイオン (Ca++) は,筋肉の収縮に重要な役割を果たします.
研究 の 目的:
- 骨格筋と滑らかな筋肉の収縮のカルシウムとマグネシウムの依存を比較するために.
- 筋筋と血管筋の収縮メカニズムにおけるマグネシウムの異なる役割を解明する.
主な方法:
- グリセリン製筋肉剤 (骨格および血管の滑らかな筋肉) を使用した.
- 自由カルシウム (Ca++) とマグネシウム (Mg++) の濃度の変化に反応して測定された筋肉の緊張.
主要な成果:
- 骨格筋と滑らかな筋肉は,収縮のために自由のCa ++に類似した依存性を示しました.
- Ca++誘発収縮の値濃度は,両方の筋肉タイプで1.8×10−7Mでした.
- 両方にとって,最大張力は10~6Mの自由Ca++をわずかに上回った.
- 滑らかな筋肉の収縮には,骨格筋と比較して少なくとも10倍のMg++濃度が必要でした.
結論:
- カルシウムイオンは,骨格筋と滑らかな筋肉の両方の収縮のための共通の調節剤として作用します.
- マグネシウムイオンは,滑らかな筋肉と骨格筋の収縮において,異なる役割を果たします.
- 滑らかな筋肉におけるより高いMg++要求は,その収縮器官に関与する異なる調節経路または結合部位を示唆する.
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