Malyapa R S, Sawada S
Department of Radiation Biology, Hiroshima University, Japan.
Radiat Res. 1991 Feb;125(2):134-40.
Cell lysis and eosin staining were observed in L5178Y cells within the first 3 h of post-hyperthermia incubation at 37 degrees C, after which both leveled to a plateau. Lysis and eosin staining were proportional to the severity of heat in asynchronous cells, whereas it was maximum in the most heat-sensitive M phase, intermediate in S, and least in heat-resistant G1 for the same heat treatment. Further, leakage of labeled [3H]thymidine and a decrease in radioactivity retained within heated cells coincided with an increase in eosin staining, indicating that the dye uptake was due to membrane damage. It was presumed that the eosin-stained fraction represented dead cells. The percentage eosin-stained cells reached a plateau, and this level was used to determine survival; when the results were compared with those obtained by the colony formation method, they were identical. By comparing the two survival assay methods we concluded that cell death after hyperthermia in L5178Y cells is mainly by interphase death in all phases of the cell cycle. The reasons for this conclusion are that a reduction in survival could be detected within one generation of L5178Y cells by the eosin staining method, and the survival values obtained by this method were identical to those obtained by the colony formation method.
在37℃热疗孵育后的最初3小时内，L5178Y细胞中观察到细胞裂解和伊红染色，之后两者均趋于平稳，达到平台期。在异步细胞中，裂解和伊红染色与热的严重程度成正比，而对于相同的热处理，在对热最敏感的M期最大，在S期居中，在耐热的G1期最小。此外，标记的[3H]胸腺嘧啶核苷的泄漏以及加热细胞内保留的放射性的降低与伊红染色的增加同时发生，表明染料摄取是由于膜损伤。据推测，伊红染色部分代表死细胞。伊红染色细胞的百分比达到平台期，该水平用于确定存活率；当将结果与通过集落形成法获得的结果进行比较时，它们是相同的。通过比较这两种存活测定方法，我们得出结论，L5178Y细胞热疗后的细胞死亡主要是细胞周期各阶段的间期死亡。得出这一结论的原因是，通过伊红染色法可以在一代L5178Y细胞内检测到存活率的降低，并且通过该方法获得的存活值与通过集落形成法获得的存活值相同。
