The Mechanism Of Ventromedial Hypothalamus Regulating Anxiety

As a common mental health problem in the general population,anxiety disorders could interrupt personal life and add to the family's financial and mental burden,the circuitries and locations involved in anxiety regulation are complex,including amygdala,hippocampus,bed nucleus of the stria terminalis(BNST)and Ventromedial hypothalamus(VMH).Recent studies indicated that VMH is not simply a downstream effector of amygdala in anxiety related circuitries,but also able to regulate the state of anxiety alone.Besides regulating anxiety,VMH could modulate its own electrophysiological activity and metabolic status,to regulate peripheral metabolic processes.Actually,anxiety can directly impose complex influences on peripheral metabolism with the involvement of VMH.However,up to now,the mechanism underlying VMH regulating anxiety remains unclear.By applying patch clamp,we explored the electrophysiological characteristics of VMH neurons.Furthermore,a chronic stress paradigm had been used to establish a mouse model of anxiety.Then,we compared the electrophysiological characteristics of VMH neurons in anxiety model mice with that of control group.Microarray had also been used to figure out the differences in gene expression between two groups.Interestingly,low threshold response and hyperpolarization current had been found in VMH neurons.According to the differences in onset time of action potential and potential sag caused by hyperpolarization current,those neurons could be divided into three types.Results of behavior tests indicated that it is feasible to induce the state of anxiety by using chronic stress paradigm.Results of Patch clamp indicated that VMH neurons in anxiety group become easier to be activated,which might be caused by the changing proportions of three types of neurons defined above.Moreover,Microarray indicated that some metabolism-related genes differentially expressed in anxiety group,which implied a potential research issue in future.