Kurihara S, Sakai T
Recent Adv Stud Cardiac Struct Metab. 1976;11:181-4.
When bathing solution temperature was lowered rapidly to below 5 degrees C, contracture was observed in toad and guinea pig cardiac muscles (Rapid Cooling Contracture, RCC). RCC in toad cardiac muscle was observed even in the presence of TTX and Mn, and enhanced by reducing [Na]o and caffeine. RCC in guinea pig cardiac muscle showed two components; phasic component was dependent on stimulation frequency before cooling, stimulation period, [Ca]o, and [Na]o; tonic component was not dependent on these factors, but was enhanced by reducing [Na]o and in high [K]o solution. From these results, the possible role of Ca ion accumulated at intracellular sequestered sites in cardiac muscle was discussed in relation to excitation-contraction (E-C) coupling.
当将浴液温度迅速降至5摄氏度以下时，在蟾蜍和豚鼠心肌中观察到挛缩（快速冷却挛缩，RCC）。即使在存在河豚毒素（TTX）和锰的情况下，蟾蜍心肌中仍可观察到RCC，并且通过降低细胞外钠离子浓度（[Na]o）和咖啡因可增强RCC。豚鼠心肌中的RCC表现为两个成分；相位成分取决于冷却前的刺激频率、刺激期、细胞外钙离子浓度（[Ca]o）和细胞外钠离子浓度（[Na]o）；紧张性成分不依赖于这些因素，但通过降低[Na]o和在高细胞外钾离子浓度（[K]o）溶液中会增强。根据这些结果，讨论了在心肌细胞内隔离部位积累的钙离子在兴奋-收缩（E-C）偶联中的可能作用。
