Esr1(+) cells in the ventromedial hypothalamus control female aggression

As an essential means to resolve conflicts, aggression is expressed by both sexes but often at a higher level in males than in females. Recent studies suggest that cells in the ventrolateral part of the ventromedial hypothalamus (VMHvl) that express estrogen receptor alpha and progesterone receptor (Esr1/PR) are essential for male but not female mouse aggression. In contrast, here we show an indispensable role of VMHvl(Esr1+) cells in female aggression. This population is active when females attack naturally. Inactivation of these cells reduces female aggression whereas their activation elicits attack. Additionally, we found that female VMHvl contains two anatomically distinguishable subdivisions that show differential gene expression, projection and activation patterns after mating and fighting. These results support an essential role of the VMHvl in both male and female aggression and reveal the existence of two previously unappreciated subdivisions in the female VMHvl that are involved in distinct social behaviors.