2Binali Yildirim University, Mengücek Gazi Education and Research Hospital, Department of Neurology, Erzincan, Türkiye
3Ordu University, Faculty of Medicine, Department of Neurology, Ordu, Türkiye
4Ordu University, Faculty of Medicine, Department of Neurosurgery, Ordu, Türkiye
5Sakarya University, Training and Research Hospital, Department of Neurology, Sakarya, Türkiye
6Hitit University, Medicine Student, Çorum, Türkiye
7Hitit University, Vocational School of Health Services, Pharmacy Services Program, Çorum, Türkiye
8Ankara Research and Training Hospital, Department of Neurosurgery, Ankara, Türkiye DOI : 10.5137/1019-5149.JTN.45526-23.4 AIM: To investigate the therapeutic and neuroprotective effects of transcranial direct current stimulation (tDCS) application on the traumatic brain injury (TBI)-induced glutamate and calcium excitotoxicity and loss of motor and cognitive functions.
MATERIAL and METHODS: Forty rats were equally divided in the sham, TBI, tDCS + TBI + tDCS, and TBI + tDCS groups. Mild TBI was induced by dropping a 450-g iron weight from a height of 1 m onto the skull of the rats. The tDCS + TBI + tDCS group was prophylactically administered 1 mA stimulation for 30 min for 7 days starting 5 days before inducing TBI. In the TBI + tDCS group, tDCS (1 mA for 30 min) was administered 2 h after TBI, on days 1 and 2. Cognitive and locomotor functions were assessed using the novel object recognition and open field tests. The calcium, glutamate, and N-methyl-D-aspartate receptor 1 (NMDAR1) levels in the hippocampus were measured using enzyme-linked immunosorbent assay.
RESULTS: Although the motor and cognitive functions were substantially reduced in the TBI group when compared with the sham, they improved in the treatment groups (p<0.05). The calcium, glutamate, and NMDAR1 levels were considerably higher in the TBI group than in the sham (p < 0.001). However, they were considerably lower in the tDCS + TBI + tDCS and TBI + tDCS groups than in the TBI groups (p < 0.05). In particular, the change in the tDCS + TBI + tDCS group was higher than that in the TBI + tDCS group.
CONCLUSION: Application of tDCS before the development of TBI improved motor and cognitive dysfunction. It demonstrated a neuroprotective and therapeutic effect by reducing the excitotoxicity via the regulation of calcium and glutamate levels.
Keywords : Calcium, Glutamate, N-methyl-d-aspartate receptor, Transcranial direct current stimulation, Traumatic brain injury, Rat