New Tool Helps Scientists Explore Rare Brain Receptors

Scientists have created a new chemical that can boost the activity of a special type of brain receptor called GluN3. These receptors are part of the larger NMDA family, which normally help brain cells talk to each other. Most research has focused on receptors that contain a different part, GluN2, but the GluN3 versions are less understood. The new compound, named UCM‑A86, works only on receptors that have GluN3. In laboratory tests, it makes the receptor’s response to its natural trigger, glycine, stronger by about 4 times for one type (GluN1/GluN3A) and nearly twice as much for another (GluN1/GluN3B). Importantly, it does not affect receptors that contain GluN2 or other common receptors called AMPA.To see if the drug works in real brain tissue, researchers applied it to mouse brain slices. They found that UCM‑A86 increased signals from GluN3 receptors in certain cells called somatostatin interneurons, which are found in the part of the brain that processes touch. It did not change signals from other receptors in the same tissue. Further experiments suggest that UCM‑A86 helps the receptor stay open longer when glycine is present, but it does not change how much charge passes through the channel. This points to a specific way the drug enhances receptor activity. Because tools that can selectively target GluN3 receptors are rare, UCM‑A86 gives researchers a new way to study how these receptors influence brain development and function. It may also help scientists explore whether GluN3 receptors play a role in brain disorders.