RESUMO
The conditions of the protein-synthesizing system in neurons of the hippocampus (areas CA1 and C A3) and of the cortex (sensomotor region) in rats subjected to y-irradiation at a dose of 8 Gy under hypothermia (16 - 18 degrees C) and hypoxia-hypercapnia were investigated by fluorescent and electron microscopy. Under hypothermia, the protein-synthesizing system was shown to be damaged to a lesser degree and to be restored faster in comparison with similar neurons in rats irradiated at room temperature. In rats irradiated under hypothermia, the rRNA biogenesis and the protein-synthesizing activity of polyribosomes were restored in two days. The protective influence of hypothermia did not spread to changes in membrane structures (endoplasmic reticulum and Golgy apparatus); i.e., a partial loss of integrity and possible transformation of their structure caused by the irradiation and the restoration of these structures occurred at a lower rate.
Assuntos
Encéfalo/efeitos da radiação , Hipotermia Induzida , Neurônios/efeitos da radiação , Lesões por Radiação/prevenção & controle , Animais , Encéfalo/ultraestrutura , Masculino , Microscopia Eletrônica , Microscopia de Fluorescência , Neurônios/metabolismo , Neurônios/ultraestrutura , Biossíntese de Proteínas/efeitos da radiação , Lesões por Radiação/patologia , Ratos , Ratos WistarRESUMO
The influence of the intestine cestode Botriocephalus gregarius on the antioxidant enzyme system in the liver and muscle of its host, the Black Sea flounder Psetta maxima maeotica, was studied. The significant increase of superoxidedismutase activity in examined tissues and changes of catalase and peroxidase activities were detected. High correlation (r > or = 0.6) between enzyme activities and the parasite number was noted. The possibility to use antioxidant enzyme activity as biomarkers of the parasite invasion in fish is discussed.