May 20, 2019
RIKEN
Ochanomizu University
Keio University School of Medicine
An international joint research group—led by Hiroshi Maunai, a visiting researcher at the Laboratory for Neuron-Glia Circuitry, RIKEN Center for Brain Science (and Assistant Professor, Faculty of Core Research, Natural Science Division, Ochanomizu University), Team Leader Hajime Hirase, and Professor Masato Yasui of the Keio University School of Medicine—has elucidated a mechanism that reduces post-ischemic brain damage by promoting the clearance mechanism of potassium ions (K+) in the brain, based on research using mice.
These research findings are expected to contribute to the elucidation of the mechanisms of tissue damage that commonly occur in various cerebrovascular disorders and to the development of therapeutic methods for them.
In cerebrovascular disorders such as stroke and traumatic brain injury, damage often expands beyond the initial site of injury into healthy tissue. This expansion of damage is known to be primarily triggered by a rapid increase in the extracellular concentration of K+ in the brain.
The international joint research group has now found that inhibiting the receptors for the neurotransmitter noradrenaline (adrenergic receptors) has neuroprotective effects and promotes the recovery of brain function after a cerebral infarction. Furthermore, by investigating the movement of water in the brain, they discovered that the inhibition of adrenergic receptors maintains the localization of aquaporin-4—a membrane protein responsible for water permeation—in astrocytes, which in turn promotes the normalization of K+ concentration.
This research was published in the online edition of the American scientific journal "Proceedings of the National Academy of Sciences (PNAS)" on May 13 (May 14, Japan time).
Please see below for the full press release.