Nasu T, Yui K, Nakagawa H, Ishida Y
Jpn J Pharmacol. 1982 Feb;32(1):65-71. doi: 10.1254/jjp.32.65.
The role of glycolysis in the tension development under anoxic conditions in a high-K medium was studied in the intestinal smooth muscle of guinea pig taenia coli. After exposure to the high-K medium (isotonic, 60 mM) under normal oxygen for 30 min, the muscles were exposed to a high-K medium bubbled with N2 gas. The tonic contraction decreased gradually to about 10% of the original level. Glucose was then cumulatively added to the high-K medium under anoxia. The maximum tension was observed following the addition of the higher concentrations of glucose. The muscle tension which developed in the high-K medium with a high concentration of glucose under anoxia was dependent on the external Ca2+ and was inhibited by iodoacetic acid (IAA). The addition of glucose to a high-K medium under anoxia also increased lactate release from the muscle. Pretreatment with 1 mM IAA decreased the lactate release from the muscle. In a Ca2+-free medium under anoxia, the addition of glucose did not increase the muscle tension although there was a significant increase in the lactate release. In summary, it is considered that the smooth muscle of taenia coli develops tension utilizing energy produced by the glycolytic pathway under anoxia in a high-K medium.
在豚鼠结肠带肠平滑肌中，研究了糖酵解在高钾培养基缺氧条件下张力发展中的作用。在正常氧气条件下，将肌肉暴露于高钾培养基（等渗，60 mM）30分钟后，再将其暴露于用氮气鼓泡的高钾培养基中。强直收缩逐渐降至原始水平的约10%。然后在缺氧条件下向高钾培养基中累积添加葡萄糖。添加较高浓度葡萄糖后观察到最大张力。缺氧条件下在含高浓度葡萄糖的高钾培养基中产生的肌肉张力依赖于细胞外Ca2+，并被碘乙酸（IAA）抑制。在缺氧条件下向高钾培养基中添加葡萄糖也会增加肌肉中乳酸的释放。用1 mM IAA预处理可减少肌肉中乳酸的释放。在缺氧的无钙培养基中，添加葡萄糖虽会使乳酸释放显著增加，但不会增加肌肉张力。总之，认为结肠带平滑肌在高钾培养基缺氧条件下利用糖酵解途径产生的能量来发展张力。
