本能视觉恐惧对执行功能的影响及其与皮质酮所致应激的关系

Effect of visually innate fear on executive function and its association with corticosterone-induced stress

目的研究本能视觉恐惧应激对小鼠糖水鉴别操作执行能力的影响,并进一步探讨此影响与皮质酮所致应激的关系。方法在小鼠中建立本能视觉恐惧及糖水学习鉴别的动物模型,并评价恐惧应激对糖水摄取操作执行行为的影响;利用酶联免疫吸附测定(ELISA)血浆皮质酮;外源注射皮质酮后观察对糖水摄取操作执行行为的影响。结果在建立本能视觉恐惧影响小鼠糖水摄取操作执行能力范式的基础上,研究发现视觉恐惧具有促进小鼠糖水摄取执行操作的趋势,但同时导致操作错误率增加;单纯糖水摄取操作组、恐惧组以及恐惧刺激伴随糖水摄取操作组的血浆皮质酮均增加,恐惧伴随糖水训练组小鼠皮质酮的增加幅度小于单纯处理组;皮质酮6.7 mg/kg导致小鼠糖水摄取操作执行行为显著增加(P<0.01),60 mg/kg皮质酮则导致操作行为下降(P<0.05),不同剂量皮质酮不影响操作正确率。结论本能视觉恐惧应激刺激对于糖水摄取操作执行行为的动机具有促进作用的趋势,但对记忆的提取可能具有一定的损害。皮质酮6.7 mg/kg使小鼠的糖水执行行为增加。从目前的结果分析,尚不能用血浆皮质酮水平变化解释视觉恐惧应激对糖水摄取操作执行功能的影响。

Objective To investigate the effect of visually innate fear on executive function in sucrose taking,and further explore the relationship between this effect and the stress induced by corticosterone.Methods The animal models for testing visually innate fear induced by looming stimulus and sucrose discrimination were established.Enzyme-linked immunosorbent assay(ELISA)was used to detect the plasma corticosterone in mice.The effect of the stress induced by corticosterone on executive function in sucrose taking was evaluated by exogenous injection of corticosterone.Results Based on the model established for evaluating the effect of visually innate fear on execution in sucrose taking in mice,we found the visually innate fear promoted the taking operations while increased the errors in this model.The plasma corticosterone in mice was increased by sucrose taking,looming stimulus,or looming stimulus along with sucrose taking,while the elevation caused by the combination of the two inducing factors was less than that caused by the single factor.The 6.7 mg/kg corticosterone caused a significant increase in the executive function in sucrose taking,while the 60 mg/kg corticosterone resulted in the decrease in the execution behavior,both without affecting the accuracy.Conclusion Visually innate fear stimulation causes an increasing motivation of executive function,and a deficit of memory retrieval in sucrose taking.The 6.7 mg/kg corticosterone promoted the executive function in mice.However,based on the analysis of the current results,the change in the plasma corticosterone level could not explain the effect of visual fear on the executive function of sucrose taking in mice.