In vitro radiation-induced effects on rat tracheal epithelial cells. I) Different radiosensitivity of cell inactivation after alpha and gamma irradiations.
In order to compare the radiotoxicity of alpha- and gamma-irradiations, primary cultures of tracheal epithelial cells from two rat strains, Sprague Dawley (SD) and Wistar Furth/Fisher F344 (WF/Fi) rats, were irradiated with 241Am alpha-particles or 60 Co gamma-rays. The survival ratio for each of the two rat strain cells appeared to be statistically different after high-LET irradiation. WF/Fi rat cells were 1.7-times more radiosensitive than SD rat cells, whereas no difference was observed following low-LET irradiation. A comparison of the cell survival yielded RBEs of 2.8 and 4.5 for SD and WF/Fi rat cells, respectively. As previously observed, with increasing LET of particles, the cell-survival curves approximate an exponential function of the dose. On the contrary, for low-LET, the survival curves showed a marked initial shoulder. This in vitro cellular model, using epithelial cells of the upper airway, provides a suitable system to estimate the mechanism involved in radiosensitivity after high-LET irradiation. The responses to radiation-induced lethal effects within a same type of cell were dependent on the irradiation parameters, but might be modulated by the individual sensitivity under genetic or epigenetic factor controls.
Kugel
Carole
C
CEA/DSV/DRR/SRCA/Laboratoire de RadioToxicologie, BP 12 91680 Bruyères-le-Châtel, France.
Bailly
Isabelle
I
Tourdes
Françoise
F
Poncy
Jean-Luc
JL
D000512:Alpha Particles / Q000009:adverse effects; D000818:Animals; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000528:radiation effects; D005720:Gamma Rays / Q000009:adverse effects; D018499:Linear Energy Transfer; D011836:Radiation Tolerance; D051381:Rats; D011916:Rats, Inbred F344; D017207:Rats, Sprague-Dawley; D014132:Trachea / Q000166:cytology / Q000528:radiation effects*