Sasa M, Takemoto I, Nishino K, Itokawa Y
J Nutr Sci Vitaminol (Tokyo). 1976 Aug;22 SUPPL:21-4. doi: 10.3177/jnsv.22.supplement_21.
Electrophysiological and biochemical studies were performed to determine the role of thiamine in the excitable membrane of the crayfish giant axons, as it has been suggested that thiamine plays a role in the excitability of the membrane which is unrelated to the metabolic process. Thiamine (5mM) significantly increased the rising rate of the action potential without affecting the resting membrane potential and threshold potential. A recovery of the enhancement was evidenced by a wash of the axon with physiological solution. Pyrithiamine (10 mM) reduced the rising rate of the action potential without affecting the membrane and threshold potential. The reduction of dV/dt by pyrithiamine remained unchanged after a wash of the axon with physiological solution, while dV/dt increased after thiamine treatment. The amount of thiamine found in the crayfish axons was comparable to that observed in the rat sciatic nerve. In addition, pyrithiamine reduced the thiamine content in axons and protein binding thiamine of the axons. It is thus concluded that thiamine in the excitable membrane of crayfish axons plays a significant role in production of the action potential and is essential for maintaining the membrane excitability of crayfish axons.
进行了电生理和生化研究，以确定硫胺素在小龙虾巨轴突可兴奋膜中的作用，因为有人认为硫胺素在膜的兴奋性中发挥作用，这与代谢过程无关。硫胺素（5mM）显著提高了动作电位的上升速率，而不影响静息膜电位和阈电位。用生理溶液冲洗轴突可证明增强作用的恢复。吡硫胺素（10mM）降低了动作电位的上升速率，而不影响膜电位和阈电位。用生理溶液冲洗轴突后，吡硫胺素对dV/dt的降低作用保持不变，而硫胺素处理后dV/dt增加。在小龙虾轴突中发现的硫胺素含量与在大鼠坐骨神经中观察到的相当。此外，吡硫胺素降低了轴突中的硫胺素含量以及轴突中与蛋白质结合的硫胺素。因此得出结论，小龙虾轴突可兴奋膜中的硫胺素在动作电位的产生中起重要作用，并且对于维持小龙虾轴突的膜兴奋性至关重要。
