Effect of Ionizing Radiation on Rat Vascular Smooth Muscle Cell.
10.4070/kcj.1998.28.8.1322
- Author:
Myung A KIM
;
In Ho CHAE
;
Sun Jung PARK
;
Joo Hee ZO
;
Hyo Soo KIM
;
Dae Won SOHN
;
Cheol Ho KIM
;
Byung Hee OH
;
Myoung Mook LEE
;
Young Bae PARK
;
Yun Shik CHOI
;
Young Woo LEE
- Publication Type:Original Article
- Keywords:
VSMCs;
gamma-irradiation;
cell cycle
- MeSH:
Animals;
Cell Count;
Cell Cycle;
Cell Cycle Checkpoints;
Cells, Cultured;
DNA;
Estrogens;
Flow Cytometry;
Glucose;
Humans;
Muscle, Smooth, Vascular*;
Myocytes, Smooth Muscle;
Radiation, Ionizing*;
Radioactivity;
Rats*;
Research Personnel;
Thymidine
- From:Korean Circulation Journal
1998;28(8):1322-1333
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Recently many investigators have reported the studies of radiation therapy to prevent proliferation of vascular smooth muscle cells (VSMCs) which is the main cause of restenosis. This work is designed to investigate the effects of gamma-radiation on the proliferation and cell cycle of VSMCs. METHOD: Rat aortic smooth muscle cells were isolated, and the cells were used between 5th and 7th passage. The cultured cells were irradiated using Cesium-137 (137Cs) with the dose of 2, 8, or 16 Gray (Gy), and harvested at 12, 24, or 48 hours after irradiation. Proliferation of cells was subsequently assessed. And the changes of DNA synthesis and cell cycle were analyzed by flow cytometry. RESULTS: 1) The number of inoculated cells was 0.4 x 105 cells/cm2. After irradiation with the dose of 0, 2, 8, or 16 Gy, cell counts at 24 hour were 3.3+/-0.9, 2.3+/-0.3, 1.9+/-0.6, 1.3+/-0.2 x 105 cells/cm2, and those at 48 hour were 5.1+/-2.1, 2.0+/-0.8, 1.8+/-0.6, 1.2+/-0.5 x 105 cells/cm2, respectively. The cells of control group grew by 56% at 48 hour compared with those at 24 hour, however the cell growth of irradiated groups was inhibited in a dose-dependent manner. 2) The inhibitory effect of irradiation was consistently observed when the culture condition was changed to high (450 mg/dl) or low glucose concentration (100 mg/dl) and with or without estrogen (180 nM of 17 beta-estradiol). 3) DNA synthesis was analysed by [3H] thymidine incorporation. Radioactivity of cells decreased significantly after irradiation (8 Gy), and this phenomenon was not influenced by various culture conditions; high aminoacid medium (with F12, high glucose concentration, or with or without estrogen). 4) The cell cycle was analyzed after irradiation. The proportions of G0/G1-S-G2/M phase in control and irradiated group were 68-14-18 vs 64-3-33% at 24 hour, 87-2-11 vs 77-2-21% at 48 hour and 86-2-12% vs 71-2-27% at 72 hour after irradiation. G1 and G2 arrest occurred at 24 hour and partial release of G2 arrest were observed at 48 hour after irradiation. CONCLUSION: The results of this study indicate that gamma-irradiation potentially inhibits the VSMCs proliferation in a dose-dependent manner by the mechanism of cell cycle arrest.
