title: Radioprotective effect of polyethylene glycol.
abstract: Polyethylene glycol of molecular weight 400 (PEG-400) had a radioprotective effect of about 20% against lethality when given ip 20 min prior to single or fractionated X-ray doses to the head and neck. Dose modification factors (DMF) based on LD50/15 values ranged from 1.14 to 1.24. A similar DMF of 1.12 based on LD50/30 values was obtained using single doses of whole-body X irradiation. Mice given head and neck irradiation had significantly reduced rectal temperatures (31.3 +/- 3.0 degrees C) 9 days post irradiation compared with unirradiated controls (35.4 +/- 0.6 degrees C). No such reduction was observed when PEG-400 was given with radiation (36.3 +/- 0.9 degrees C). PEG-400 also lessened, but not significantly, the frequency of shivering in irradiated animals. Histopathologic examination of the oral structures demonstrated only marginal protection by PEG-400. Estimation of the alpha/beta ratio from LD50 data on head and neck-irradiated mice yielded values of 4.4 +/- 1.9 (95% confidence limits) Gy without PEG-400 and 7.9 +/- 1.4 Gy with PEG-400. Since it is a non-thiol radioprotector, PEG-400 may be more useful when combined with more conventional thiol-containing radioprotectors.
mesh_terms: D000818:Animals; D006257:Head / Q000528:radiation effects; D008297:Male; D051379:Mice; D009333:Neck / Q000528:radiation effects; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011833:Radiation Injuries, Experimental / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000627:therapeutic use*; D012768:Shivering / Q000528:radiation effects; D014916:Whole-Body Irradiation
chemical_list: D011837:Radiation-Protective Agents; D011092:Polyethylene Glycols