Study Finds Ketamine Anesthesia Alters Female Brain Networks via Microglia

Researchers at the Institute of Science and Technology Austria and the Allen Institute in Seattle reported that ketamine anesthesia triggers distinct changes in the brains of female mice. After the anesthetic, immune cells called microglia increased their interaction with neurons, leading to more frequent excitatory signals and a reorganization of neural networks. The effect was linked to a rise in corticosterone, a stress hormone, which activated signaling pathways in microglia. Male mice did not show these changes. The findings, published in Science Advances, suggest that ketamine may affect female brain recovery differently, raising questions about its impact on women undergoing the drug in clinical settings.

The study used a combination of ketamine, xylazine and acepromazine, and employed cranial windows and fluorescent markers to visualize microglia and neurons in the visual cortex. While the immediate post‑anesthetic period showed little change, the female mice exhibited heightened microglial activity and altered synaptic connectivity in the hours that followed.