The effects of chronic repetitive transcranial magnetic stimulation on glutamate and gamma-aminobutyric acid in rat brain.

Recent studies have shown that repetitive transcranial magnetic stimulation (rTMS) has therapeutic potential for some neurological and psychiatric disorders. However, the neurobiological effects of this tool are not sufficiently explained so far, previous research reported that rTMS can change dopamine release, there have been few studies to examine a possible effect of rTMS on amino acid neurotransmitter. This study aimed to determine the effects of chronic rTMS on glutamate and gamma-aminobutyric acid concentration in the rat brain. Sprague–Dawley rat was subject to 500 pulses of 0.5 Hz rTMS for 15 days, or sham stimulation. After last stimulation, glutamate and gamma-aminobutyric acid content were measured by high performance liquid chromatography (HPLC). Results showed that the content of glutamate and gamma-aminobutyric acid increased significantly in hippocampus and striatum after chronic rTMS, but reduced significantly in the hypothalamus. These results indicate that chronic rTMS has a modulatory effect on the glutamate and gamma-aminobutyric acid systems. This change in amino acid neurotransmitter may contribute to its beneficial effects.