RESUMO
The resistance of mice to whole-body irradiation with lethal doses, after preirradiation of part of the abdomen, was studied with a reference to radiation dose, the volume of local exposure, and the interval between exposures. The radioresistance was found to increase when the preirradiated zone corresponded to the spleen projection, the interval between exposures was 3-7 days, and the dose of local exposure, 2 Gy.
Assuntos
Abdome/efeitos da radiação , Tolerância a Radiação , Irradiação Corporal Total/mortalidade , Animais , Medula Óssea/efeitos da radiação , Transplante de Medula Óssea , Ensaio de Unidades Formadoras de Colônias , Relação Dose-Resposta à Radiação , Sistema Hematopoético/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Baço/efeitos da radiação , Fatores de TempoRESUMO
The data are presented on radioresistance of mice 1, 5 and 9 months after irradiation (LD95-99/30) in conditions of protection with cystamine. It was shown that the resistance of these animals to repeated irradiation with LD50/30 is considerably lower than that of the animals not exposed previously. The radioresistance and such indices of the haemopoietic system status as quantity of caryocytes and colony-forming capacity of the bone marrow are compared.
Assuntos
Lesões Experimentais por Radiação/mortalidade , Tolerância a Radiação , Protetores contra Radiação/uso terapêutico , Animais , Medula Óssea/efeitos da radiação , Ensaio de Unidades Formadoras de Colônias , Cistamina/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/patologiaRESUMO
Cellularity and colony-forming ability of stromal (CFUf) and haemopoietic (CFUc) bone marrow stem cells have been studied at different times after irradiation. The results obtained are indicative of the similarity between the kinetics of the damage and repair of stromal and haemopoietic stem cells.
Assuntos
Células-Tronco Hematopoéticas/efeitos da radiação , Animais , Contagem de Células , Radioisótopos de Césio , Ensaio de Unidades Formadoras de Colônias , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Fatores de TempoRESUMO
The comparative data are presented concerning the 30-day restoration of the bone marrow cellularity and the number of endogenous colonies in the spleen of the control animals and of those treated with the radioprotective agents after irradiation with doses from 4.5 to 8.1 Gy. There was a good agreement between the results of studies in the integrity of the haemopoietic system on day 9 after irradiation and the 30-day survival of animals.