Modulatory Effect And Mechanism Of Stress-induced Anxiety-like Behavior By Subtypes Of Calbindin Neurons In PVN

Paraventricular nucleus(PVN)of the hypothalamus is one of the key nuclei in the initiation and modulation of stress response.Calbindin is an intracellular calcium-binding protein,it is present in subtypes of neurons in various stress-related brain regions.Calbindin modulates intracellular calcium homeostasis and synaptic plasticity,and it is related to stress.Up to now,direct evidence is lacking for the role of PVN calbindin in stress-induced anxiety-related behavior.In this study,we found that calbindin partially colocalizes with arginine vasopressin(AVP)and corticotropin releasing hormone(CRH)in the adult mouse PVN.Using adeno-associated virus(AAV),we found that knock-down of PVN calbindin levels or specific reductions of calbindin levels in PVN AVP neurons could increase anxiety-like behavior in mice.These results suggest that reductions of calbindin levels in PVN neurons can lead to anxiety-like behavior.Therefore,calbindin in PVN neurons(especially AVP neurons)plays an important role in modulating anxiety-like behavior.