Publications by authors named "Mai Hatano"
Local and global functional connectivity densities (lFCD and gFCD, respectively), derived from functional magnetic resonance imaging (fMRI) data, represent the degree of functional centrality within local and global brain networks. While these methods are well-established for mapping brain connectivity, the molecular and synaptic foundations of these connectivity patterns remain unclear. Glutamate, the principal excitatory neurotransmitter in the brain, plays a key role in these processes.
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- Researchers developed a new PET tracer, [C]K-2, that allows for the visualization and measurement of AMPAR density in the brains of living human patients, which is important for understanding neurotransmission in psychiatric disorders.
- The study involved 149 patients with various psychiatric disorders (like schizophrenia and bipolar disorder) and 70 healthy individuals, revealing correlations between AMPAR density and symptom severity.
- The findings highlight unique patterns of AMPAR distribution across different psychiatric disorders, suggesting potential new approaches for diagnosing and treating these conditions based on biological mechanisms.
The excitatory glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) contribute to epileptogenesis. Thirty patients with epilepsy and 31 healthy controls are scanned using positron emission tomography with our recently developed radiotracer for AMPARs, [C]K-2, which measures the density of cell-surface AMPARs. In patients with focal-onset seizures, an increase in AMPAR trafficking augments the amplitude of abnormal gamma activity detected by electroencephalography.
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- Identifying the epileptogenic zone before surgery is crucial for effective seizure control in epilepsy patients.
- Elevated levels of glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors are found in the brains of epilepsy patients, but their role in triggering seizures is still uncertain.
- A new PET tracer, [C]K-2, has been developed to visualize these receptors, and studies show higher uptake in the temporal lobe of patients with mesial temporal lobe epilepsy, indicating a link between these receptors and the initiation of seizures.
Article Synopsis
- This study investigates [C]K-2, a radiotracer that targets AMPARs, for measuring their levels in living human brains and identifying potential epileptic areas.
- Twelve healthy male participants received different doses of [C]K-2 and underwent whole-body scans to measure radiation exposure in various organs.
- Results showed that while the liver and brain had significant uptake of [C]K-2, the urinary bladder received the highest radiation dose, with the overall effective dose found to be safe for PET studies.
Although aberrations in the number and function of glutamate AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptors are thought to underlie neuropsychiatric disorders, no methods are currently available for visualizing AMPA receptors in the living human brain. Here we developed a positron emission tomography (PET) tracer for AMPA receptors. A derivative of 4-[2-(phenylsulfonylamino)ethylthio]-2,6-difluoro-phenoxyacetamide radiolabeled with C ([C]K-2) showed specific binding to AMPA receptors.
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