Effects Of Voluntary Exercise And Environmental Enrichment During Puberty On Social Behavior In Male Mice And Their Neural Mechanism

Social behavior is a very conservative and complex social behavior in biological evolution.It is a process of mutual stimulation and reaction between two or more individuals,which is regulated by the central nervous system.Previous studies have shown that the amygdala plays an important role in social behavior.In addition,social behavior can be affected by external factors such as sports and environment.Previous research results on the influence of different forms of exercise on social behavior are inconsistent,and most of them are concentrated in adulthood and middle and old age,and the neural mechanism is also unclear.However,brain and behavior during development are more susceptible to external factors.At the same time,compared with involuntary exercise,autonomous exercise can avoid the physiological and psychological pressure on individuals.In this study,three groups of conditions were used to intervene the developing mice(21d-60d),namely,independent running wheel exercise,environmental enrichment,and independent running wheel exercise combined with environmental enrichment.After5 w conditional intervention,the social behavior of mice in each group was detected by three-room social interaction method.Then the micro-excitation postsynaptic currents(m EPSCs)and micro-inhibitory postsynaptic currents(m IPSCs)of amygdala neurons were measured by whole-cell patch clamp recording technique.The research results show that:1.During the development period,the mice experienced a single independent running wheel exercise,which could increase the sociality without changing the social novelty.At the same time,it increased the frequency and amplitude of m EPSCs of amygdala neurons,but did not change the frequency and amplitude of m EPSCs of amygdala neurons.It shows that the single independent running wheel exercise during the development period has an impact on social behavior and has no impact on the inhibitory synaptic transmission of amygdala neurons,but it can enhance its excitatory synaptic transmission through presynaptic and postsynaptic mechanisms.2.The single environmental enrichment in developing mice did not change their sociality and social novelty,and neither m EPSCs nor m IPSCs of amygdala neurons were changed,indicating that the single environmental enrichment in developing mice had no effect on social behavior and excitatory and inhibitory synaptic transmission of amygdala neurons.3.The experience of independent running wheel exercise combined with environmental enrichment in developing mice can significantly increase their sociality,but has no effect on social novelty.At the same time,it significantly increases the frequency and amplitude of m EPSCs and m IPSCs in amygdala neurons,indicating that the experience of exercise combined with environmental enrichment in developing mice can improve social ability,and increase the excitability and inhibitory synaptic transmission of amygdala neurons through presynaptic and postsynaptic mechanisms.The above research results suggest that the ability of social behavior can be effectively improved by independent exercise and environmental enrichment during development,and also suggest that the amygdala participates in a potential cellular mechanism to regulate this process.At the same time,this study can provide theoretical support and reference for revealing the role of sports in promoting preschool education and behavior development,and has certain practical guiding significance.