Gerweck L E, Richards B
Cancer Res. 1981 Mar;41(3):845-9.
The hyperthermic sensitivity of cultured human glioblastoma cells was determined in 1 degree increments from 42 through 46 degrees over the pH range of 6.1 to 7.4. These cells were 5 to 10 times less heat sensitive than were Chinese hamster ovary cells and are among the most resistant cells examined in cell culture. At pH 7.4, the rate of cell killing doubles with each 1 degree increase in temperature above 44 degrees, a phenomenon previously observed in other cell lines heated above 43 degrees. It is speculated that thermotolerance develops during heat treatment and accounts for this apparent resistance to heat below 44 degrees. Reduction in medium pH from 7.4 to 7.0 during heat treatment did not significantly influence thermal sensitivity; however, below pH 7.0 a pH-sensitizing effect was increasingly evident. The magnitude of this sensitizing effect, determined from survival curve slope ratios, was temperature dependent and was most pronounced at temperatures which were moderately lethal at pH 7.4. At pH 6.7, heat sensitivity was increased from a factor of congruent to 1.25 at 46-44 degrees to 2 at 43 degrees compared to treatment at pH 7.4. This pH-sensitizing effect and its temperature dependency was more pronounced at pH 6.1.
在6.1至7.4的pH范围内，以1摄氏度的增量从42摄氏度到46摄氏度测定培养的人胶质母细胞瘤细胞的热敏感性。这些细胞的热敏感性比中国仓鼠卵巢细胞低5至10倍，是细胞培养中检测到的最具抗性的细胞之一。在pH 7.4时，温度高于44摄氏度每升高1摄氏度，细胞杀伤率就会加倍，这一现象先前在加热到43摄氏度以上的其他细胞系中也有观察到。据推测，热耐受性在热处理过程中形成，并解释了在44摄氏度以下对热的这种明显抗性。热处理期间培养基pH从7.4降至7.0对热敏感性没有显著影响；然而，在pH 7.0以下，pH敏感效应越来越明显。这种敏感效应的程度由存活曲线斜率比确定，与温度有关，在pH 7.4时具有中等致死性的温度下最为明显。在pH 6.7时，与pH 7.4处理相比，热敏感性从46 - 44摄氏度时的约1.25倍增加到43摄氏度时的2倍。这种pH敏感效应及其温度依赖性在pH 6.1时更为明显。
