抄録
It is well known that the stress is one of the most influential factors on the cardiovascular disorder. In the animal studies, influence of physical stresses such as restrained stress and electric shock stress is well examined, but the attempt to explore the influence of mental stress on the circulatory system especially on the blood fluidity and the level of reactive oxygen metabolites is few. In this study, we designed a model that loaded more mental stress rather than physical stress on rats. Male Wistar rats weighing 100-120 g were used in the experiment. Rat was isolated in the very narrow space surrounded by water, just like the isolated animal in a small island (SIS), for 24, 72 and 120 hours. Water and standard diet were freely available. After stress load, blood sample was collected from the femoral vein under nembutal anesthesia using heparin as anticoagulants. Blood fluidity was measured by MC-FAN (Micro-channel Array Flow Analyzer) and the value of oxidative stress was estimated by the reactive oxygen metabolites (ROMs) value using d-ROM test system. Results showed that ROMs were significantly increased in SIS group than that of the control group, and the blood fluidity of rats under 72 and 120 hours SIS was also significantly lower than that of the control group. These results indicate that the present stress model, small island stress, beneficially loads stress to rats with more mental and less physical stress factors. This model might be useful for the animal study of mental stress. [J Physiol Sci. 2008;58 Suppl:S216]
