5-HT Receptors on Dentate Gyrus Granule Cells Confer Stress Resilience.

Background: Hyperactivity of granule cells in the ventral dentate gyrus (vDG) promotes vulnerability to chronic stress. However, which receptors in the vDG could be targeted to inhibit this hyperactivity and confer stress resilience is not known. The serotonin 1A receptor (5-HTR) is a G protein-coupled inhibitory receptor that has been implicated in stress adaptation, anxiety, depression, and antidepressant responses.

Adult-born hippocampal neurons bidirectionally modulate entorhinal inputs into the dentate gyrus.

Young adult-born granule cells (abGCs) in the dentate gyrus (DG) have a profound impact on cognition and mood. However, it remains unclear how abGCs distinctively contribute to local DG information processing. We found that the actions of abGCs in the DG depend on the origin of incoming afferents.

Hippocampal neurogenesis confers stress resilience by inhibiting the ventral dentate gyrus.

Adult neurogenesis in the dentate gyrus of the hippocampus is highly regulated by environmental influences, and functionally implicated in behavioural responses to stress and antidepressants. However, how adult-born neurons regulate dentate gyrus information processing to protect from stress-induced anxiety-like behaviour is unknown. Here we show in mice that neurogenesis confers resilience to chronic stress by inhibiting the activity of mature granule cells in the ventral dentate gyrus (vDG), a subregion that is implicated in mood regulation.