Subdiaphragmatic vagotomy reduces hypothalamic oxytocin expression and blood levels after oral MDMA administration in male rats.
Progress in neuro-psychopharmacology & biological psychiatry – March 20, 2025
Source: PubMed
Summary
The vagus nerve, a key player in the gut-brain axis, significantly influences how MDMA affects hormone levels in the body. When researchers severed this nerve in rats, they found dramatically reduced oxytocin levels in both blood and brain regions, particularly in the paraventricular and supraoptic nucleus. This reveals how crucial the connection between digestive and nervous systems is for MDMA's well-known emotional and social effects.
Abstract
3,4-Methylenedioxymethamphetamine (MDMA) is a widely recognized entactogen frequently used recreationally. It is known for its interaction with the serotonin and oxytocin systems, which underlie its entactogenic effects in humans. Recently, we demonstrated that the gut-brain axis, mediated by the subdiaphragmatic vagus nerve, contributes to MDMA-induced resilience enhancement in rodents. This study investigates whether subdiaphragmatic vagotomy (SDV) affects plasma oxytocin levels and the expression of oxytocin and c-Fos in the hypothalamus following a single oral dose of MDMA in rats. SDV significantly reduced baseline plasma oxytocin levels and oxytocin expression in the paraventricular and supraoptic nuclei of the hypothalamus. Furthermore, SDV markedly attenuated MDMA-induced increases in plasma oxytocin and the expression of oxytocin and c-Fos in these hypothalamic regions. These findings suggest that the subdiaphragmatic vagus nerve plays a critical role in brain-body communication, mediating MDMA's pharmacological effects on the oxytocin system.