https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/72 2026-07-04T22:39:29Z 2026-07-04T22:39:29Z Kwak, Youngjong Rojas Cabrera, Juan M. Vettleson-Trutza, Sara A. Scheitler, Kristen M. Karanovic, Una Oesterle, Tyler S. Blaha, Charles D. Oh, Yoonbae Shin, Hojin Jang, Dong Pyo Lee, Kendall H. https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/212523 2026-05-09T05:01:25Z 2026-10-01T00:00:00Z

Title: Effects of oxycodone on tonic levels and phasic release of serotonin in the rat nucleus accumbens core Authors: Kwak, Youngjong; Rojas Cabrera, Juan M.; Vettleson-Trutza, Sara A.; Scheitler, Kristen M.; Karanovic, Una; Oesterle, Tyler S.; Blaha, Charles D.; Oh, Yoonbae; Shin, Hojin; Jang, Dong Pyo; Lee, Kendall H. Abstract: Despite widespread oxycodone misuse, the role of serotonin in opioid addiction remains understudied compared to dopamine. This study investigated the acute effects of oxycodone (2.5 mg/kg, i.v.) on serotonergic neurotransmission in the rat nucleus accumbens core using high-resolution electrochemical methods. We employed fast-scan cyclic voltammetry (FSCV) to monitor medial forebrain bundle stimulation-evoked phasic release and N-shaped multiple cyclic square wave voltammetry (N-MCSWV) to measure tonic concentrations in urethane-anesthetized rats. Results demonstrated a distinct dissociation between tonic and phasic dynamics. Tonic serotonin levels increased significantly (+23.4 nM) from baseline 1-h post-administration. Conversely, stimulation-evoked phasic release initially increased (+24%) but subsequently declined below baseline. Kinetic analysis revealed that serotonin production and maximum reuptake rates followed a similar pattern of initial increase followed by a decrease. In conclusion, oxycodone acutely modulates serotonergic signaling in the nucleus accumbens core by differentially affecting phasic and tonic neurotransmission. These findings demonstrate oxycodone induces temporal dynamics in phasic versus tonic serotonergic signaling in the nucleus accumbens core, highlighting the value of multimodal electrochemical approaches for dissecting opioid neurochemical effects.

2026-10-01T00:00:00Z Lee, Youngeun Lina Reva, Maria Kim, Ki Jung Kim, Hyun-Jin Kim, Yemin Cho, Eunjeong Jeong, Minseok Kwak, Youngjong Myung, Kyungjae Li, Yulong Lee, Seung Eun Jang, Dong Pyo Lee, C. Justin Lüscher, Christian Kim, Jae-Ick https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/213302 2026-06-16T07:00:19Z 2026-04-01T00:00:00Z

Title: Distinct modes of dopamine modulation on striatopallidal synaptic transmission Authors: Lee, Youngeun Lina; Reva, Maria; Kim, Ki Jung; Kim, Hyun-Jin; Kim, Yemin; Cho, Eunjeong; Jeong, Minseok; Kwak, Youngjong; Myung, Kyungjae; Li, Yulong; Lee, Seung Eun; Jang, Dong Pyo; Lee, C. Justin; Lüscher, Christian; Kim, Jae-Ick Abstract: Dopamine affects voluntary movement by modulating basal ganglia function. However, the contribution of dopamine on striatopallidal synapses, an initial hub in the indirect pathway connecting the striatum to the GPe, remains poorly understood because of the sparse dopaminergic innervation. Here, we combine optogenetic projection targeting, whole cell patch clamp recordings in acute brain slices from mice, and computational modeling to overcome this limitation. We show that dopamine activates D2 receptors (D2Rs) and D4 receptors (D4Rs) differentially in distinct GPe subregions. In a pinwheel-like fashion, dorsolateral and ventromedial GPe expresses high levels of D2Rs, which exert presynaptic inhibition, while in dorsomedial and ventrolateral GPe D4Rs cause postsynaptic inhibition. Dopamine depletion by 6-OHDA reshapes the region-specific effect of dopamine, shifting it in the opposite direction and contributing to hypokinesia. These findings reveal the mechanism by which the different modality information conveyed spatially through the indirect pathway is differentially modulated by dopamine at striatopallidal synapses..

2026-04-01T00:00:00Z Kim, Hyunjoong Cho, Sanghyeon Kim, Myeong Woo Park, Chan Sam Lee, Kwangmuk Song, Solwoong Keum, Dae Sik Lee, Sangmoon Jeong, Hoon Eui Jang, Dong Pyo Kim, Jae Joon https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/213955 2026-06-22T05:00:12Z 2026-04-01T00:00:00Z

Title: A Behind-The-Ear Patch-Type Mental Healthcare Integrated Interface with Adaptive Multimodal Offset Compensation and Parasitic Cancellation Authors: Kim, Hyunjoong; Cho, Sanghyeon; Kim, Myeong Woo; Park, Chan Sam; Lee, Kwangmuk; Song, Solwoong; Keum, Dae Sik; Lee, Sangmoon; Jeong, Hoon Eui; Jang, Dong Pyo; Kim, Jae Joon Abstract: A behind-the-ear (BTE) integrated interface for mental healthcare applications is presented, featuring optimized BTE electrode configurations and wide multimodal biomedical IC with adaptive compensation capabilities. The proposed IC supports 8 bio-potential (ExG), 1 photoplethysmogram (PPG), 1 galvanic skin response (GSR), 1 bio-impedance (BioZ), and 2 stimulation channels. The ExG channel achieves 2.5GΩ input impedance, boosted by 308 times with offset compensated auxiliary path (OCAP) architecture, and its AC input impedancecharacteristic is boosted further by dual resolution external positive feedback loop (DR-EPFL) scheme. An area and energy-efficient GSR-embedded ECG recording scheme is presented. For comprehensive multimodal sensing features, dual-slope PPG channel with parasitic capacitance compensation, electrode-tissue impedance adaptive stimulator, and high dynamic range BioZ channel are integrated. The IC was fabricated in a 0.18-μm BCD process and integrated into a BTE patch-type device prototype. System-level feasibility was experimentally verified through in-vivo stress measurements with virtual reality (VR) environment, demonstrating effective mental health monitoring capabilities.

2026-04-01T00:00:00Z Higham, Simon J. Cabrera, Juan M. Rojas Kwak, Youngjong Hong, Lydia Chambers, Andre Nadarajah, Athavan De Leon, Sorel E. Jung, Young Jun Jalilinejad, Negin Blaha, Charles Jang, Dong Pyo Oh, Yoonbae Lee, Kendall Stacey, Alastair Cloherty, Shaun L. Ibbotson, Michael R. Garrett, David J. Prawer, Steven Shin, Hojin Tong, Wei https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/214332 2026-06-23T01:00:19Z 2026-04-01T00:00:00Z

Title: Boron-Doped Nano-Crystalline Coated Carbon Fibers for Phasic Dopamine Sensing Authors: Higham, Simon J.; Cabrera, Juan M. Rojas; Kwak, Youngjong; Hong, Lydia; Chambers, Andre; Nadarajah, Athavan; De Leon, Sorel E.; Jung, Young Jun; Jalilinejad, Negin; Blaha, Charles; Jang, Dong Pyo; Oh, Yoonbae; Lee, Kendall; Stacey, Alastair; Cloherty, Shaun L.; Ibbotson, Michael R.; Garrett, David J.; Prawer, Steven; Shin, Hojin; Tong, Wei Abstract: Real time, chronic electrochemical detection of neurotransmitters will provide a positive step in the treatment and understanding of neurological disease. However, current electrodes using carbon fibers (CF) fail to perform chronically. While diamond-based coatings show promise in improving their longevity, achieving a uniform layer of such coatings on CFs is challenging, and the electrodes often lose sensitivity after coating. In this work, a complete and uniform boron-doped nanocrystalline material grown in a diamond reactor (B-NCD) was developed to coat CF microelectrodes for neurochemical sensing. The coating was characterized electrically, optically, mechanically, and chemically. The B-NCD coated CF electrodes were able to detect phasic dopamine at a sensitivity comparable to the most widely used alternatives (uncoated and PEDOT:Nafion coated CFs). During biofouling testing, the B-NCD coated CF electrodes demonstrated better stability than uncoated CFs and comparable performance to PEDOT:Nafion coated CFs. Moreover, B-NCD exhibited no signs of degradation during consecutive FSCV applications, while uncoated and PEDOT:Nafion coated CF electrodes degraded significantly over time. Furthermore, the B-NCD coating supported the survival and development of neurons and astrocytes in vitro, exhibited excellent adhesion and durability during mechanical bending testing, and enabled successful in vivo recording of phasic dopamine release in the rat brain. Overall, B-NCD coated CFs present as an ideal candidate for chronic, flexible neural implantable electrodes for long-term neurochemical monitoring.

2026-04-01T00:00:00Z