Therapeutic effects of anodal transcranial direct current stimulation in a rat model of ADHD
- Pusan National University, Republic of Korea
- Dongseo University, Republic of Korea
Abstract
Most therapeutic candidates for treating attention deficit hyperactivity disorder (ADHD) have focused on modulating the dopaminergic neurotransmission system with neurotrophic factors. Regulation of this system by transcranial direct current stimulation (tDCS) could contribute to the recovery of cognitive symptoms observed in patients with ADHD. Here, male spontaneously hypertensive (SHR) rats were subjected to consecutive high-definition tDCS (HD-tDCS) (20 min, 50 μA, current density 63.7 A/m2, charge density 76.4 kC/m2) over the prefrontal cortex. This treatment alleviated cognitive deficits, with an increase in tyrosine hydroxylase and vesicular monoamine transporter 2 and significantly decreased plasma membrane reuptake transporter (DAT). HD-tDCS application increased the expression of several neurotrophic factors, particularly brain-derived neurotrophic factor (BDNF), and activated hippocampal neurogenesis. Our results suggest that anodal HD-tDCS over the prefrontal cortex may ameliorate cognitive dysfunction via regulation of DAT and BDNF in the mesocorticolimbic dopaminergic pathways, and therefore represents a potential adjuvant therapy for ADHD.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures and Tables
Article and author information
Author details
Funding
National Research Foundation of Korea (2018R1A2A2A05018926)
- Byung Tae Choi
National Research Foundation of Korea (2014R1A5A2009936)
- Byung Tae Choi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Marom Bikson
Ethics
Animal experimentation: All experiments were approved by the Pusan National University Animal Care and Use Committee and were performed in accordance with the National Institutes of Health Guidelines (PNU-2018-1932)
Version history
- Received: February 25, 2020
- Accepted: September 19, 2020
- Accepted Manuscript published: September 21, 2020 (version 1)
- Version of Record published: October 5, 2020 (version 2)
Copyright
© 2020, Jung et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Therapeutic effects of anodal transcranial direct current stimulation in a rat model of ADHD
eLife 9:e56359.
https://doi.org/10.7554/eLife.56359
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