title: Radioprotection by polyethylene glycol-protein complexes in mice.
abstract: Polyethylene glycol of about 5000 D was activated with cyanuric chloride, and the activated compound was complexed to each of three proteins. Polyethylene glycol-superoxide dismutase and polyethylene glycol-catalase were each radioprotectants when administered prophylactically to female B6CBF1 mice before irradiation. The dose reduction factor for these mice was 1.2 when 5000 units of polyethylene glycol-catalase was administered before 60Co irradiation. Female B6CBF1 mice administered prophylactic intravenous injections of catalase, polyethylene glycol-albumin, or heat-denatured polyethylene glycol-catalase had survival rates similar to phosphate-buffered saline-injected control mice following 60Co irradiation. Polyethylene glycol-superoxide dismutase and polyethylene glycol-catalase have radioprotective activity in B6CBF1 mice, which appears to depend in part on enzymatic activities of the complex. However, no radioprotective effect was observed in male C57BL/6 mice injected with each polyethylene glycol-protein complex at either 3 or 24 hr before irradiation. The mechanism for radioprotection by these complexes may depend in part on other factors.
mesh_terms: D000818:Animals; D002374:Catalase / Q000494:pharmacology*; D005260:Female; D007928:Lethal Dose 50; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011833:Radiation Injuries, Experimental / Q000517:prevention & control; D011837:Radiation-Protective Agents; D013482:Superoxide Dismutase / Q000494:pharmacology*; D014916:Whole-Body Irradiation
chemical_list: D011837:Radiation-Protective Agents; D011092:Polyethylene Glycols; D002374:Catalase; D013482:Superoxide Dismutase