RESUMO
We used cytogenetic analysis in the studies of the biological effects of a radiation factor of natural and artificial origin (under conditions ofthe 30-km exclusion zone ofthe Chernobyl experimental landfills in Ukraine, Belarus and Russia). The studies have been performed on various types of mammals: domestic animals--cows, pigs, horses and rodents--root voles, the Af mouse line, and yellow necked field mouse, bank voles. We found significant changes in the level of MN and chromosomal aberrations in the animals that were exposed to the conditions of chronic low-dose radiation for a long time (bothin the habitat and upon exposure in the Chernobyl zone) regardless of the type of animal and nature of contamination.
Assuntos
Acidente Nuclear de Chernobyl , Aberrações Cromossômicas/efeitos da radiação , Mutagênese/genética , Doses de Radiação , Animais , Arvicolinae/genética , Relação Dose-Resposta à Radiação , Cavalos/genética , Camundongos , Mutagênese/efeitos da radiação , República de Belarus , Federação Russa , Suínos/genética , UcrâniaRESUMO
The state of hematopoietic, reproductive and endocrine systems of the organisms of male rats and their offspring in generations (F0-F1-F2) was studied, and the sensitivity of an organism to the action of carcinogen (Af mice) after a stay in the ChNPP exclusion zone was analyzed. It was ascertained that the most significant changes of the morphofunctional state of the animals were observed in the II generation (F2), which remained for a long period under the conditions of radioactive contamination. We have revealed an increased number of leukocytes, neutrophils, lymphocytes, and, especially, monocytes as against while the decrease in the number of erythrocytes and haemoglobin content; the decrease of thyroid function and cortical layer of the adrenals as opposed to while the increase in the relative weight of testes and their epididymides and the decrease in the number of spermatocytes and spermatozoa in the testis tissue. The exposure of Af mice in the exclusion zone increases the processes of mutagenesis and carcinogenesis, and changes the organism response to standardized action of chemical carcinogen. The increase in the exposure time of animals intensifies metabolic processes in a cell and increases their sensitivity to the action of xenobiotics.
Assuntos
Carcinoma de Ehrlich/etiologia , Acidente Nuclear de Chernobyl , Cocarcinogênese , Neoplasias Induzidas por Radiação/etiologia , Efeitos Tardios da Exposição Pré-Natal/sangue , Lesões Experimentais por Radiação/sangue , Animais , Contagem de Células Sanguíneas , Cálcio/sangue , Relação Dose-Resposta à Radiação , Sistema Endócrino/crescimento & desenvolvimento , Sistema Endócrino/efeitos da radiação , Eritrócitos/efeitos da radiação , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Tamanho do Órgão/efeitos da radiação , Fósforo/sangue , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/patologia , Lesões Experimentais por Radiação/genética , Lesões Experimentais por Radiação/patologia , Ratos , Reprodução/efeitos da radiação , Glândulas Seminais/crescimento & desenvolvimento , Glândulas Seminais/efeitos da radiação , Análise de Sobrevida , Testículo/crescimento & desenvolvimento , Testículo/efeitos da radiaçãoRESUMO
The cycle of researches of the influence of an exposion of mice of line Af in the conditions of the zone of Chernobyl disaster on spontaneous and chemically induced mutability, lung tumour (adenomas), morphological and functional condition of alveolar macrophages, and also genetic effects in natural populations wild rodents is executed. The increase in polychromatic frequency in mouse bone marrow, adenomas in lungs, and change of sensitivity of an organism to action mutagen and transgenerational transfer of genetic damages is shown.
Assuntos
Transformação Celular Neoplásica/genética , Acidente Nuclear de Chernobyl , Ecologia , Mutagênese/efeitos da radiação , Neoplasias Induzidas por Radiação/genética , Lesões Experimentais por Radiação/genética , Adenoma/genética , Adenoma/patologia , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Medula Óssea/efeitos da radiação , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/patologia , Eritrócitos Anormais/efeitos da radiação , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/patologia , Macrófagos Alveolares/efeitos da radiação , Camundongos , Camundongos Endogâmicos , Mutagênicos/toxicidade , Neoplasias Induzidas por Radiação/patologia , Lesões Experimentais por Radiação/patologia , República de BelarusRESUMO
Studying of dose and time dependences of frequency of adenomas appearing under the combined effect of radiation and urethane ingressed during different terms after irradiation has show that the frequency of tumours is determined both by radiation dose, and the time interval between irradiation and ingressing of cancerogenic substance. The data obtained show the period of preservation of the induced damages and non-linearity of the process of tumour-formation under the combined effect of radiation and toxic factors on the organism. The latter is necessary to be taken into account when forecasting the radiation risk under the real ecological conditions.
Assuntos
Adenoma/etiologia , Carcinógenos/toxicidade , Neoplasias Pulmonares/etiologia , Uretana/toxicidade , Animais , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Camundongos , Neoplasias Induzidas por Radiação/etiologia , Fatores de TempoRESUMO
In the experiment with combined influence of single or prolonged gamma irradiation (35 cGy) and chemical agents (urethanum, nitrogen oxide) on the induction of chromosome aberrations in bone marrow cells and lung tumor the effect of dose rate was studied. The frequency of chromosome aberrations increased with dose rate. Yet the correlation between the ratio of irreparable (stable) aberrations and dose rate was of inverse direction. The character of variations in lung adenoma frequency under multifactor influence in the case of prolonged irradiation (increase with dose rate decrease) supports the correlation between the level of stable aberrations in the pool of genetic lesions and the frequency of lung adenoma.
Assuntos
Adenoma/etiologia , Carcinógenos/toxicidade , Aberrações Cromossômicas , Neoplasias Pulmonares/etiologia , Neoplasias Induzidas por Radiação/etiologia , Óxidos de Nitrogênio/toxicidade , Uretana/toxicidade , Adenoma/epidemiologia , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/efeitos da radiação , Medula Óssea/ultraestrutura , Relação Dose-Resposta à Radiação , Raios gama , Incidência , Neoplasias Pulmonares/epidemiologia , Camundongos , Neoplasias Induzidas por Radiação/epidemiologia , Fatores de TempoRESUMO
In studying the combined effect of single and fractionated exposure to gamma/neutron radiation (12.5-50 cGy) and sodium nitrite (100 mg/kg) and chronic irradiation with a mixture of radiation (25 cGy) and sodium nitrite, nitrate (10-100 mg/l) the synergistic effect was observed in inducing reciprocal translocations in mouse spermatocytes. The dose-response function of the reciprocal translocations occurrence in Af mouse spermatocytes was nonlinear; there was a "plateau" within the dose range from 25 to 50 cGy.