A new study uncovers how progesterone-responsive neurons in the anterior ventromedial hypothalamus (VMH) toggle between sexual receptivity and rejection in female mice. These neurons are highly active during rejection behaviors, such as kicking or boxing males, when females are outside their fertile phase. During fertility, these neurons receive inhibitory signals, reducing their activity and enabling mating. Using advanced techniques like optogenetics, researchers confirmed that activating these neurons induces rejection even in fertile females, while silencing them decreases rejection behaviors without triggering receptivity.
