Radiation protection against early and late effects of ionizing irradiation by the prostaglandin inhibitor indomethacin.
Protective effects of indomethacin, a prototype prostaglandin-inhibiting agent, against early and late sequelae of radiation injury (after X-rays or gamma rays) in mice were investigated.  The following tissues or organs were examined:  hematopoietic tissue, esophagus, jejunum, colon, lung, hair follicles, and tissues involved in the development of radiation-induced leg contractures.  In addition, the effect of indomethacin was tested against radiation-induced carcinogenesis.  In all experiments, the radiation was delivered as a single dose.  Indomethacin led to significant protection of hematopoietic tissue, by a factor of 1.3.  There was also some protection against radiation-induced pneumonitis and against radiation-induced carcinogenesis (protection factor of 1.2).  The other tissues tested showed no change in their radioresponse after being treated with indomethacin.  Thus, indomethacin can act as a radioprotective agent against both early and late sequelae of radiation, but its effect is dependent on the tissue tested.  This protection is smaller than that observed with WR-2721.  However, indomethacin combined with WR-2721 produced a radioprotective effect greater than the radioprotection achieved by individual treatments.
Milas
L
L
Department of Experimental Radiotherapy, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
Nishiguchi
I
I
Hunter
N
N
Murray
D
D
Fleck
R
R
Ito
H
H
Travis
E
E
D004999:Amifostine / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D003286:Contracture / Q000517:prevention & control; D004064:Digestive System / Q000187:drug effects / Q000528:radiation effects; D004359:Drug Therapy, Combination; D005720:Gamma Rays; D018859:Hair Follicle / Q000187:drug effects / Q000528:radiation effects; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000528:radiation effects; D006413:Hematopoietic System / Q000187:drug effects / Q000528:radiation effects; D007213:Indomethacin / Q000494:pharmacology / Q000627:therapeutic use*; D007866:Leg; D008168:Lung / Q000187:drug effects / Q000528:radiation effects; D051379:Mice; D008815:Mice, Inbred Strains; D009381:Neoplasms, Radiation-Induced / Q000517:prevention & control; D011833:Radiation Injuries, Experimental / Q000188:drug therapy* / Q000401:mortality / Q000517:prevention & control; D011836:Radiation Tolerance / Q000187:drug effects; D011837:Radiation-Protective Agents / Q000627:therapeutic use*; D011878:Radiotherapy / Q000009:adverse effects / Q000379:methods*
D011837:Radiation-Protective Agents; D004999:Amifostine; D007213:Indomethacin