Subanesthetic ketamine can treat adult amblyopia, a brain disorder commonly called “lazy eye,” research finds.
“Our study, demonstrates how a single-dose of subanesthetic ketamine reactivates adult visual cortical plasticity and promotes functional recovery of visual acuity defects resulting from amblyopia,” explains Xiangmin Xu, professor of anatomy and neurobiology and director of the Center for Neural Circuit Mapping at the University of California, Irvine School of Medicine.
Subanesthetic ketamine, commonly used to treat depression and pain, evokes rapid and long-lasting antidepressant effects in human patients. There was evidence that ketamine may control how the nervous system makes structural changes in response to internal and external demands, a process called neural plasticity. How the drug works has remained elusive.
“Our research team showed that ketamine down-regulates NRG1 expression in PV inhibitory cells, resulting in sustained cortical disinhibition to enhance cortical plasticity in adult visual cortex,” says Steven F. Grieco, postdoctoral scholar in the Xu lab and lead author of the paper in Current Biology.
“Through this neural plasticity-based mechanism, ketamine mediated functional recovery from adult amblyopia.”
Amblyopia is a vision disorder in which the brain fails to process inputs from one eye, favoring the other eye. The condition can result in decreased vision in the affected eye. Each year, between 1 and 5% of children worldwide are diagnosed with this condition.
Fast and sustained ketamine actions show promise for therapeutic applications that rely on reactivating adult cortical plasticity. Further testing will be necessary to determine the full implications of this discovery.
Support for the study came from the National Institutes of Health.
Source: UC Irvine