Remani P, Ostapenko V, Akagi K, Tanaka Y
Division of Cancer Research, Regional Cancer Centre, Thiruvananthapuram, India.
Neoplasma. 1998;45(2):73-6.
The effect of hyperthermia on transmembrane potential was studied in HeLa cells in vitro using a 3',3'-dipentyl oxacarbocyanine [Di-0-C5(3)], a lipophilic cation probe that equilibrates across the plasma membrane according to the transmembrane potential. Uptake of the fluorescent probe was measured by flow cytometry. The flourescent intensity (FI) increased with increase in temperature, and the increase was statistically significant when the duration of heat treatment was 30 minutes or more. At each temperature studied the depolarization was higher after longer duration of heat treatment (p value: 41 degrees C < 0.05; 42 degrees C < 0.005; 43 degrees C < 0.001 and 44 degrees C < 0.001, respectively). The lack of significant depolarization after shorter duration of heating, particularly at lower temperatures could be due to the repair of membrane damage that could have occurred in the holding interval between heating and measurement. The results suggest that depolarization of membrane potential, i.e. increase in the intracellular cation concentration, can be considered as an indicator of cell injury by hyperthermia and may be mechanistically related to cell death by heat treatment. The technique may be suitable for studying repair of damage after hyperthermia.
利用3',3'-二戊基草酰羰花青[Di-0-C5(3)]，一种根据跨膜电位在质膜上达到平衡的亲脂性阳离子探针，在体外研究了高温对HeLa细胞跨膜电位的影响。通过流式细胞术测量荧光探针的摄取量。荧光强度（FI）随温度升高而增加，当热处理持续时间为30分钟或更长时，这种增加具有统计学意义。在每个研究温度下，热处理持续时间越长，去极化程度越高（p值：41℃时<0.05；42℃时<0.005；43℃时<0.001；44℃时<0.001）。较短时间加热后缺乏明显的去极化，尤其是在较低温度下，可能是由于在加热和测量之间的保持间隔中可能发生的膜损伤的修复。结果表明，膜电位的去极化，即细胞内阳离子浓度的增加，可以被视为高温引起细胞损伤的指标，并且在机制上可能与热处理导致的细胞死亡有关。该技术可能适用于研究高温后损伤的修复。
