Increased reactivity of the paraventricular nucleus of the hypothalamus and decreased threat responding in male rats following psilocin administration.
Nature Communications June 22, 2024 Devin P. Effinger, Jessica L Hoffman, Sarah E Mott et al. 15 citations
Psilocin, the psychoactive metabolite of psilocybin, increases activity in the paraventricular nucleus of the hypothalamus (PVN) in rats, a brain region central to stress response, autonomic function, and social behavior. In male rats, psilocin heightened PVN reactivity to an aversive air-puff stimulus, driven by active threat responders, while females showed no such increase. This effect was temporary, with reactivity returning to baseline 2 and 7 days after injection. Prior psilocin did not alter PVN reactivity during acute restraint stress. The findings identify the PVN as a key site of psychedelic action with implications for threat-related behavior.