Yoon, Bo-Eun Woo, Junsung Chun, Ye-Eun Chun, Heejung Jo, Seonmi Bae, Jin Young An, Heeyoung Min, Joo Ok Oh, Soo-Jin Han, Kyung-Seok Kim, Hye Yun Kim, Taekeun Kim, Young Soo Bae, Yong Chul Lee, C. Justin 2024-01-20T08:31:31Z 2024-01-20T08:31:31Z 2021-09-02 2014-11-15 0022-3751 https://pubs.kist.re.kr/handle/201004/126116 GABA is the major inhibitory transmitter in the brain and is released not only from a subset of neurons but also from glia. Although neuronal GABA is well known to be synthesized by glutamic acid decarboxylase (GAD), the source of glial GABA is unknown. After estimating the concentration of GABA in Bergmann glia to be around 5-10 mM by immunogold electron microscopy, we demonstrate that GABA production in glia requires MAOB, a key enzyme in the putrescine degradation pathway. In cultured cerebellar glia, both Ca2+-induced and tonic GABA release are significantly reduced by both gene silencing of MAOB and the MAOB inhibitor selegiline. In the cerebellum and striatum of adult mice, general gene silencing, knock out of MAOB or selegiline treatment resulted in elimination of tonic GABA currents recorded from granule neurons and medium spiny neurons. Glial-specific rescue of MAOB resulted in complete rescue of tonic GABA currents. Our results identify MAOB as a key synthesizing enzyme of glial GABA, which is released via bestrophin 1 (Best1) channel to mediate tonic inhibition in the brain. English WILEY-BLACKWELL CEREBELLAR GRANULE CELLS GAMMA-AMINOBUTYRIC-ACID HIPPOCAMPAL CA1 RAT CEREBELLUM BRAIN-TISSUE ASTROCYTES RECEPTORS NEURONS RELEASE PUTRESCINE Glial GABA, synthesized by monoamine oxidase B, mediates tonic inhibition Article 10.1113/jphysiol.2014.278754 1 JOURNAL OF PHYSIOLOGY-LONDON, v.592, no.22, pp.4951 - 4968 JOURNAL OF PHYSIOLOGY-LONDON 592 22 4951 4968 scie scopus 000345773100012 2-s2.0-84922119726 Neurosciences Physiology Neurosciences & Neurology Physiology Article CEREBELLAR GRANULE CELLS GAMMA-AMINOBUTYRIC-ACID HIPPOCAMPAL CA1 RAT CEREBELLUM BRAIN-TISSUE ASTROCYTES RECEPTORS NEURONS RELEASE PUTRESCINE