Gillies R J, Deamer D W
J Cell Physiol. 1979 Jul;100(1):23-31. doi: 10.1002/jcp.1041000103.
The equilibrium distribution of 5,5-dimethyloxazoladine 2,4-dione (DMO) between intra- and extracellular volume was used to estimate intracellular pH (pHi) in Tetrahymena pyiformis. In control experiments, DMO was found to equilibrate rapidly in response to a pH gradient. Under normal growth conditions, pHi was constant over a finite range of external pH, being maintained near pH 7.1 over the external pH range 5.2 to 7.3. This same range of external pH was also optimal for growth. pHi was monitored during the cell cycle of a synchronous population of T. pyriformis GL. The cells were synchronized either by starvation/refeeding or heat shock. Under both conditions, there were two alkaline shifts of approximately 0.4 pH units per cell cycle. These shifts in pH retained a constant remporal relationship to S phase and were not affected by changes in the time, duration, or magnitude of cytokinesis.
利用5,5-二甲基恶唑烷-2,4-二酮（DMO）在细胞内液和细胞外液之间的平衡分布来估计梨形四膜虫的细胞内pH（pHi）。在对照实验中，发现DMO会响应pH梯度而迅速达到平衡。在正常生长条件下，在有限的外部pH范围内，pHi保持恒定，在外部pH范围5.2至7.3时维持在pH 7.1附近。这个相同的外部pH范围对生长也是最佳的。在梨形四膜虫GL同步群体的细胞周期中监测pHi。细胞通过饥饿/再投喂或热休克进行同步化。在这两种条件下，每个细胞周期都有大约0.4个pH单位的两次碱性转变。这些pH转变与S期保持恒定的时间关系，并且不受胞质分裂时间、持续时间或幅度变化的影响。
