Kosaka T, Tsukahara M, Kaneko I, Nakano K, Tanaka S, Koide F
Department of Veterinary Radiology, Nihon University, Kanagawa, Japan.
Int J Radiat Biol. 1995 Jun;67(6):687-91. doi: 10.1080/09553009514550811.
Hypertonic treatment (0.5 M NaCl in phosphate-buffered saline, pH 7.2) at 37 degrees C for 20 min slightly delayed the mitotic frequency for non-irradiated cells in G1 and G2 phases. The mitotic frequency for irradiated cells in G2 was delayed by hypertonic treatment, and that in G1 was slightly delayed by hypertonic treatment. Hypertonic treatment in non-irradiated cells did not induce any chromosomal or chromatid aberrations in either G1 or G2. Chromosomal aberrations caused by gamma-irradiation were slightly enhanced by hypertonic treatment, and chromatid aberrations were markedly enhanced by hypertonic treatment. The enhancement ratio of gamma-irradiation-induced chromatid breaks and exchanges was 1.4 and 3.0, respectively. This cell cycle dependency of chromosome aberrations induced by postirradiation hypertonic treatment was the same as that of cell survival. These findings suggested that hypertonic treatment modifies the rejoining of DNA strand breaks in G2, but slightly modifies that in G1.
在37℃下用高渗处理（在pH 7.2的磷酸盐缓冲盐水中加入0.5 M NaCl）20分钟，会使处于G1期和G2期的未受辐照细胞的有丝分裂频率略有延迟。高渗处理会延迟处于G2期的受辐照细胞的有丝分裂频率，而处于G1期的受辐照细胞的有丝分裂频率则略有延迟。高渗处理未在处于G1期或G2期的未受辐照细胞中诱导任何染色体或染色单体畸变。高渗处理会使γ射线辐照引起的染色体畸变略有增强，而染色单体畸变则明显增强。γ射线辐照诱导的染色单体断裂和交换的增强率分别为1.4和3.0。辐照后高渗处理诱导的染色体畸变的这种细胞周期依赖性与细胞存活的情况相同。这些发现表明，高渗处理会改变G2期DNA链断裂的重新连接，但对G1期的影响较小。
