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Objective: To establish conditioned fear stress model rat conditioned fear stress conditions stress response and brain damage indicators integrated detection, analysis, evaluation, screening anti-fear drug efficacy evaluation order for anti-terror The pharmacodynamic evaluation index system established to provide information. Methods: 64 healthy male Wistar rats were randomly divided into fear stress group and control group, n = 32. Food and water freely raised for 10 days after the first 11 days the fear model group administered daily 2s noise 3s plantar current stimulation, the current strength of 1mA, interval 1min, a total of 30 times; daily control group given only 2s noise, without plantar current stimulation interval 1min, a total of 30 times. 6 ~ 30min within 14 days after the camera records two groups of rats 5min noise changes in behavior, whether to establish evaluation model. A week at first, second, third and fourth weeks since the model (18,25,32,39 days) week two groups of rats a general state of stress behavioral responses (freezing time, spontaneous activity observed and measured) and physiological responses (the serum corticosterone COR) and brain damage (NSE NSE, hippocampus morphology). Results: 1. The fear model rats freeze behavior school score was significantly higher than the control group (P lt; 0.01) shows that the establishment of conditioned fear stress model is effective. 2 the fear model rats compared with the control group, in a different time period of 4 weeks showed an air of tired, the hair disheveled dull, decrease in food intake, loose stool phenomenon; groups of rats weight showed growth fear model group weight gain than the control group slowly 2 weeks (P lt; 0.05), three weeks (P lt; 0.05), 4 weeks (P lt; 0.01) groups of rats weight compare differences were significant. 3 the fear model group compared with the control group, in different time period of 4 weeks showed irritability, more tussle behavior, reduced activity, get together and lazy phenomenon; spontaneous activity comparison of the two groups of rats, fear model group time to rest in the first week (P lt; 0.05), 2 weeks (P lt; 0.01), 3 weeks (P lt; 0.05), 4 weeks (P lt; 0.05) were significantly more than the control group. Compare the two groups in serum corticosterone content, fear levels of serum corticosterone concentration in one week (P lt; 0.05), 2 weeks (P lt; 0.01), 3 weeks (P lt; 0.05), 4 weeks (P lt; 0.05) were significantly higher than the control group. Compare the two groups in serum NSE levels, fear model serum NSE concentration was significantly higher in the first week (P lt; 0.05), the rest of the week were not statistically different; slices of rat hippocampus with HE staining results showed the control group rat hippocampal CA1 and CA3 pyramidal cells in the dentate gyrus (DG) granule cells morphologically normal cells neatly close level, cell integrity, sharp edges, nucleoli visible; fear stress rats to stress one week, two weeks of the hippocampal CA1, CA3 region, dentate gyrus (DG) cell volume swelling, cells lightly stained cells arranged slightly sparse three weeks cell atrophy, cell gap increases, the cell level thinning, interrupted the first four weeks, the cells irregular decrease in the number of cells, loosely arranged arrhythmia, a large number of cell necrosis, nuclear condensation, rupture phenomenon. Conclusion: The results of this study show that, after the modified Takeuchi Act can establish conditioned fear stress model, conditioned fear stress induced acute, chronic stress induced by fear, affect the physiological responses of rats and behavioral responses induced brain injury. The results provide the basis for the fear of the stress response and brain damage effects and to provide information to the anti-fear drug efficacy evaluation index system establishment.
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