Establishment Of Mice Fear-related Empathy Model And Investigation Of The Mechanism

In this dissertation, we have established a empathic behavior model of mice, and investigated some possible mechanism of empathy. The dissertation contians3parts as below:1. Establishing an empathic behavior paradigm in mouse and analyzing important elements of this paradigmOur study is based on the existing literatures, using C57B/6J mouse as experimental subjects, comparing two reported behavioral test models, and eventually, building up an optimized behavioral paradigm of empathy. The key element of this paradigm is an obtained aversive experience of experimental mouse, with this point, mouse shows an excellent response to empathy event. In addition, we further investigate some other elements’influences to empathy in this model including the tension of obtained aversive experience, related contextual memory and so on.2. Applying the empathic paradigm to a transgenic mouse strainIn this part, we use Dat-Cre mouse as experimental subject to evaluate if this transgenic mouse model could be used for the further investigation of empathic behavior. Despite of abnormal nest building ability, this mouse model shows normal locomotor activity, anxiety, depression and motor abilities. In addition, the transgenic mouse has no deficit in empathy test, indicates that this mouse model could be used for the further investigation of empathy.3. Discussing on the mechanism of empathic behavior----using norepinephrine to regulate empathic behaviorNorepinephrine is one of the most important emotional hormones. The report about the relationship between norepinephrine and empathy is limited. Our investigation uses C57BL/6J mouse as experimental subjects, intraperitoneal inject epinephrine to elevate norepinephrine level in central nervous system, as a result, the empathic behavior in low level experienced group significantly enhanced by epinephrine compared to control group. We use propranolol, a β-adrenergic receptor blocker, to decrease the empathic behavior in the high level experience group mice subsequently. Further, our experiments also found that epinephrine can disturb the emotion maintenance of the high level experience group, the epinephrine cannot evoke empathic behavior of mice without aversive treatment.