Long lasting effect of acute restraint stress on behavior and brain anti-oxidative status

Abstract

Exposure to certain acute stressors results in an immediate behavioral and physiological response to these situations during a significant period of days. The goal of the current study is to evaluate the long-lasting effect of single exposure of restraint stress among mice after 0 h, 24 h, 48 h and 72 h. Five groups of mice are under experiment: a control group and four groups exposed to one session of restraint stress. All these groups have been studied for behavioral tests in order to evaluate their memories. This is done through a Y-labyrinth and an object recognition test, and anxiety by using open field device. In the second part of the study, enzymatic assays (concerning catalase, glutathione s transferase, glutathione peroxidase and superoxide dismutase) are used to evaluate oxidative stress. The enzymatic activity of the antioxidant system is assessed in five brain structures, including the cerebellum, olfactory bulb, spinal bulb, hypothalamus, and hippocampus. The obtained results show that acute restraint stress leads to a decrease in memory function and to the development of an anxious state; concomitant to an increase of locomotor activity afterword. It causes disturbance of antioxidant balance in the brain by developing a state of oxidative stress. Indeed, restraint stress causes a change in anti-oxidant stress enzymatic activity in the brain, notably in post-stress period. In conclusion, acute restraint stress is responsible for altering cognitive functions, especially memory, and the development of anxious behavior, which could be a result of the generation of oxidative stress; effects that are persistent over an important period after the cessation of stress.