title: Enhanced cell killing, inhibition of recovery from potentially lethal damage and increased mutation frequency by 3-aminobenzamide in Chinese hamster V79 cells exposed to X-rays.
abstract: X-ray induced potentially lethal damage and its inhibition by the aromatic amide 3-aminobenzamide have been investigated in Chinese hamster V79 cells. 3-Aminobenzamide (3-AB) is a known inhibitor of polyadenosine diphosphoribose synthetase. With increasing concentrations of 3-AB an increasing inhibition of PLD repair was observed. Little inhibition of PLD repair was seen when 3-AB was added 3 h following irradiation. Utilizing the 6-thioguanine mutation assay, the effect of poly(ADP-R) synthetase inhibition under conditions of PLD repair upon mutation frequency were also studied. A large increase in mutation frequency following 24 h post-irradiation recovery in the presence of 3-AB was seen. These results favour a possible role of 3-AB in preventing repair by facilitating early damage fixation before repair can occur, simultaneously reducing G2-arrest.
mesh_terms: D000818:Animals; D001549:Benzamides / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects*; D006224:Cricetinae; D003412:Cricetulus; D004260:DNA Repair / Q000187:drug effects / Q000528:radiation effects*; D003864:Depression, Chemical; D004307:Dose-Response Relationship, Radiation; D066298:In Vitro Techniques; D009154:Mutation; D013268:Stimulation, Chemical; D013997:Time Factors
chemical_list: D001549:Benzamides; C025160:3-aminobenzamide