RESUMO
Whole-body irradiation of mice with gamma-rays at 14 Gy causes DNA single and double strand breaks effectively repaired later. p53 is accumulated during the repair period. There is still some amount of DNA breaks 48-72 hours after the irradiation. Despite p53 accumulation and residual DNA lesions in the cells, mice retina demonstrated no morphological destructive changes or apoptosis signs. Retina resistance to apoptotic signals could derive from efficient repair of radiation-induced lesions in transcriptionally active regions of the genome of differentiated cells.
Assuntos
Reparo do DNA , DNA/efeitos da radiação , Raios gama/efeitos adversos , Tolerância a Radiação , Retina/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , DNA/genética , Dano ao DNA , Feminino , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Retina/fisiologia , Retina/ultraestrutura , Irradiação Corporal TotalRESUMO
30 mg of ascorbic acid and 80 mg of dry oats extracts were administered to rats with alloxan diabetes during a day per 1 kg of live weight. Administration of these preparations during 6, 12 and 24 days prevents the uncoupling action of respiration and oxidative phosphorylation, that was observed in the rats with alloxan diabetes which were not given ascorbic acid and oats polyphenols. The P/O coefficient on the alloxan diabetes rats on the 6, 12 and 24 days was 1.32 +/- 0.027; 1.26 +/- 0.013; 1.22 +/- 0.18, respectively; in the rats which were given ascorbic acid and oats polyphenols to P/O coefficient was 1.85 +/- 0,026, 1.80 +/- 0.024 and 1.75 +/- 0.028, respectively.