RESUMO
It is known that a single session of high-intensity interval exercise (HIIE) contributes to the increase of the reactive species of oxygen, accompanied by a greater antioxidant activity. However, it is poorly understood if a single session of HIIE has similar effects on the brain tissue. This study evaluated the effects of a single HIIE on the hippocampal redox status. Sixteen males Wistar rats were allocated into HIIE (nâ¯=â¯8) and control (nâ¯=â¯8) groups. Maximum oxygen consumption (VO2max) was evaluated using a treadmill at 10° inclination in a metabolic chamber. HIIE group was submitted to a single run on the treadmill composed by 10 bouts of high-intensity exercise of 1â¯min each (85-100% of VO2max), at 28â¯m/min, 10° inclination, interspersed by 2â¯min of active recovery, at 10â¯m/min, with no inclination. Analysis of the redox status at the hippocampus were conducted 24â¯h after the HIIE session. It was not identified lipid peroxidation in the hippocampus of the HIIE group (Control 1.9⯱â¯0.31, vs HIIT 2.2⯱â¯0.53â¯nmol MDA/mg protein (pâ¯>â¯.05). However, the activity of the superoxide dismutase (Control 2.614⯱â¯0.225 vs HIIT 3.718⯱â¯0.4589â¯U/mg protein), and the non-enzymatic total antioxidant capacity (Control 1584⯱â¯75.88 vs HIIT 1984⯱â¯137.7â¯nM FeSO4/mg protein) were enhanced (pâ¯<â¯.05) after the exercise session. These results indicate that the antioxidant mechanisms are enhanced even after a single session of HIIE. A single session of HIIE does not induce lipid peroxidation and improves the antioxidant defenses in Wistar rats' hippocampus.
Assuntos
Antioxidantes/metabolismo , Treinamento Intervalado de Alta Intensidade , Hipocampo/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Peroxidação de Lipídeos/fisiologia , Masculino , Oxirredução , Consumo de Oxigênio/fisiologia , Ratos , Ratos WistarRESUMO
Discutimos aqui aspectos vinculados ao enquadramento legal, a recomendações internacionais e a programas de formação em proteção radiológica; ao angiógrafo e à qualidade da imagem; aos efeitos biológicos e aos riscos das radiações ionizantes; às lesões em operadores e pacientes; aos níveis de referência do paciente; ao limite de dose ocupacional e a suas medidas de prevenção. O uso das radiações ionizantes acarreta riscos, que, contudo, justificam-se em procedimentos diagnósticos e terapêuticos. A consciência e o conhecimento desses riscos minimizam o dano, otimizando a qualidade da imagens e o uso seguro das radiações ionizantes. Tem-se demonstrado a ocorrência de cataratas radioinduzidas em trabalhadores de laboratórios de cateterismo. Diversos estudos sugerem que pode haver um risco significativo de opacidade do cristalino, caso não se utilizem adequadamente os dispositivos de proteção radiológica. Adicionalmente, esses tipos de procedimentos intervencionistas são realizados na América Latina, geralmente por médicos especialistas, com a colaboração de enfermeiros, tecnólogos e técnicos, que, muitas vezes, não têm formação adequada em proteção radiológica.
We discuss some aspects related to the legal framework, international recommendations and training programs on radiological protection; image quality and equipment; the biological effects and risks of ionizing radiation; lesions in patients and operators; patient's reference levels; occupational dose limit and preventive actions. The use of ionizing radiation involves risks that are justified in diagnostic and therapeutic procedures. The awareness and knowledge of these risks minimizes the damage, optimizing the quality of images and safe use of ionizing radiation. There is evidence of radiation-induced cataracts in individuals who work in catheterization laboratories. Several studies suggest there may be a significant risk of lens opacity, if radiological protection devices are not properly used. Additionally, these interventional procedures are performed in Latin America, usually by medical specialists in collaboration with nurses, technologists and technicians, who often do not have adequate training in radiological protection.
