The Ventral Hippocampus Controls Stress-Provoked Impulsive Aggression through the Ventromedial Hypothalamus in Post-Weaning Social Isolation Mice

Abstract

Summary: Impulsively aggressive individuals may suddenly attack others when under stress, but the neural circuitry underlying stress-provoked aggression is poorly understood. Here, we report that acute stress activates ventral hippocampus (vHip) neurons to induce attack behavior in post-weaning socially isolated mice. Chemogenetic inhibition of vHip neural activity blunts stress-provoked attack behavior, whereas chemogenetic activation promotes it. The activation of cell bodies in vHip neurons projecting into the ventromedial hypothalamus (VMH) induces attack behavior, suggesting that the vHip-VMH projection contributes to impulsive aggression. Furthermore, optogenetic inhibition of vHip glutamatergic neurons blocks stress-provoked attacks, whereas optogenetic activation of vHip glutamatergic neurons drives attack behavior. These results show direct evidence that vHip-VMH neural circuitry modulates attack behavior in socially isolated mice. : Individuals with a tendency toward impulsive aggression may suddenly attack others when under stress. The neural circuitry underlying stress-provoked aggression is largely unknown. Chang and Gean demonstrate that ventral hippocampal (vHip) outputs to the ventromedial hypothalamus (VMH) mediate stress-provoked aggression in post-weaning socially isolated mice. Keywords: ventral hippocampus, ventromedial hypothalamus, impulsive aggression, acute stress, chemogenetic, optogenetic approaches