【Animal Modeling】-Effect of plantar shock stress duration on anxiety-like behavior in rats

  OBJECTIVE: To observe the effects of plantar shock stress duration on the elevated plus maze and anxiety-like behaviors in the opening test in rats.

  Methods: Adult male SD rats were randomly divided into control group and foot shock group according to body weight stratification, with 12 rats in each group. In the plantar electric shock group, inescapable plantar electric shock (0.8 mA, electric shock for 10 s, rest for 20 s, a total of 5 min, once a day) was combined with solitary feeding to establish a rat anxiety model. The elevated plus maze and the opening field test were measured 7 days and 14 days after the foot shock, respectively, to evaluate the anxiety behavior of the rats.

  RESULTS: After 7 days and 14 days of foot shock, the anxiety-like behavior in the foot shock group increased, and the difference was significant (P < 0.01). The number of times of entering the central area and the duration of stay in the central area of the foot shock group in the opening experiment were lower than those of the control group (P < 0.01), and the total movement distance, the number of erection times and the number of grooming were significantly lower in the foot shock group than those in the control group (P < 0.01). , exercise exploration activity decreased. Comparing the behavioral results of the 7-day and 14-day plantar shock groups, it can be seen that with the increase of modeling days, the ratio of time to arm closure and the ratio of arm closure times showed a downward trend (P < 0.05), and the degree of anxiety decreased. The total distance of exercise, the number of standing uprights and the number of grooming for 14 days were lower than 7 days in the opening experiment, and the difference was significant (P < 0.05), suggesting that the rats' exercise exploration behavior was further reduced, self-focus was reduced, and depression-like behavior was increased.

  CONCLUSION: The plantar shock stress of different durations induces anxiety-like behaviors in rats and affects the motor exploration activity of rats. With the increase of modeling days, the behavior of rats may change from anxiety-like to depression-like. The choice of 7 d is better than 14 d for the model-making time course of plantar shock stress anxiety model.