November 28, 2022

Astrocytes in the Brains of Epileptic Mice Exhibit an Acid Response with Intensified Seizures

Article published by News Medical

Researchers at Tohoku University have shown that astrocytes in the mouse brain exhibit an acid response with intensified epileptic seizures. The astrocytes’ acid response could lead to the amplification of excitatory neuronal signals and be the underlying drive for generating plasticity for epileptogenesis.

The findings were detailed in the journal Brain on November 25, 2022.

Cells in the brain can be divided into neurons and glia. Astrocytes are a major subtype of glia, controlling the local ionic and metabotropic environment in the brain.

To better understand astrocytes and the brain environment, fluorescent sensor proteins were genetically expressed in the astrocytes of mice. The researchers then implanted an optical fiber into the lateral hypothalamus of the mouse brain, to send excitation light and record fluorescence signals. By analyzing the signals recorded with this newly devised fiber photometry method, astrocytes’ activity was evaluated and critical components of local brain environmental changes were dissected.

The researchers were not the first to employ fiber photometry technology, but most previous studies have neglected the effects of local blood volume and cytosolic pH changes on the detected fluorescence signals. Lead study investigator Dr. Yoko Ikoma, Matsui, and their team, however, broadened the analysis of detected fluorescence signals to extract as much of the local environmental parameters as possible.