title: Near-infrared stimulation on globus pallidus and subthalamus.
abstract: Near-infrared stimulation (NIS) is an emerging technique used to evoke action potentials in nervous systems. Its efficacy of evoking action potentials has been demonstrated in different nerve tissues. However, few studies have been performed using NIS to stimulate the deep brain structures, such as globus pallidus (GP) and subthalamic nucleus (STN). Male Sprague-Dawley rats were randomly divided into GP stimulation group (n=11) and STN stimulation group (n=6). After introducing optrodes stereotaxically into the GP or STN, we stimulated neural tissue for 2 min with continuous near-infrared light of 808 nm while varying the radiant exposure from 40 to 10 mW. The effects were investigated with extracellular recordings and the temperature rises at the stimulation site were also measured. NIS was found to elicit excitatory responses in eight out of 11 cases (73%) and inhibitory responses in three cases in the GP stimulation group, whereas it predominantly evoked inhibitory responses in seven out of eight cases (87.5%) and an excitatory response in one case in STN stimulation group. Only radiation above 20 mW, accompanying temperature increases of more than 2°C, elicited a statistically significant neural response (p<0.05). The responsiveness to NIS was linearly dependent on the power of radiation exposure.
authors.affiliation: Gwangju Institute of Science and Technology (GIST), Department of Medical System Engineering, Gwangju, Republic of Korea.
authors.forename: Minsu
authors.initials: M
authors.lastname: Yoo
authors.affiliation: Wonkwang University School of Medicine, Department of Physiology, Iksan, Republic of Korea.
authors.forename: Ho
authors.initials: H
authors.lastname: Koo
authors.affiliation: Wonkwang University School of Medicine, Department of Physiology, Iksan, Republic of Korea.
authors.forename: Minsun
authors.initials: M
authors.lastname: Kim
authors.affiliation: Gwangju Institute of Science and Technology (GIST), Department of Medical System Engineering, Gwangju, Republic of KoreacGwangju Institute of Science and Technology (GIST), School of Mechatronics, Gwangju, Republic of KoreadPresbyterian Medical Center, Department of Neurosurgery, Jeonju, Republic of Korea.
authors.forename: Hyoung-Ihl
authors.initials: HI
authors.lastname: Kim
authors.affiliation: Gwangju Institute of Science and Technology (GIST), Department of Medical System Engineering, Gwangju, Republic of KoreacGwangju Institute of Science and Technology (GIST), School of Mechatronics, Gwangju, Republic of Korea.
authors.forename: Sohee
authors.initials: S
authors.lastname: Kim
mesh_terms: D000200:Action Potentials / Q000528:radiation effects; D000818:Animals; D004594:Electrophysiology; D004867:Equipment Design; D005917:Globus Pallidus / Q000502:physiology / Q000528:radiation effects*; D007259:Infrared Rays / Q000009:adverse effects / Q000627:therapeutic use; D007834:Lasers; D028022:Low-Level Light Therapy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D020530:Subthalamus / Q000502:physiology / Q000528:radiation effects*; D013696:Temperature