Optical measurement of glutamate in slice preparations of the mouse retina. (December 2018)

• Record Type: Journal Article
• Authors: Ohkuma, M.; Kaneda, M.; Yoshida, S.; Fukuda, A.; Miyachi, E.
• Is Part Of: Neuroscience research. Volume 137(2018)
• Page Start: 23
• Page End: 29
• Publication Date: 2018-12
• Subjects: TBOA dl-threo-β-benzyloxyaspartic acid -- GDH glutamate dehydrogenase -- HEPES 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid -- NADH nicotinamide adenine dinucleotide (reduced form) -- NAD+ nicotinamide adenine dinucleotide (oxidized form) -- ROI region of interest -- OS the outer segment of photoreceptor -- ONL the outer nuclear layer -- OPL the outer plexiform layer -- INL the inner nuclear layer -- IPL the inner plexiform layer -- GCL the ganglion cell layer; Retina -- Glutamate -- Mouse -- Imaging; Neurosciences -- Research -- Periodicals; Neurosciences -- Research -- Japan -- Periodicals; Neurology -- Periodicals; Neurosciences -- Periodicals; Neurosciences -- Recherche -- Périodiques; Neurosciences -- Recherche -- Japon -- Périodiques; Neurosciences -- Research; Japan; Periodicals; 612.8
• DOI: 10.1016/j.neures.2018.03.001
• Languages: English
• ISSNs: 0168-0102

Abstract

Highlights: We used a new imaging technique to monitor glutamate dynamics in the mouse retina. High K solutions elevated the glutamate signal. Cd 2+ blocked the K-induced elevation of glutamate. Blocking GABA- and glycinergic inputs elevated the glutamate signal. Abstract: Signaling by glutamatergic synapses plays an important role in visual processing in the retina. In this study, we used an enzyme-linked fluorescence assay system to monitor the dynamics of extracellular glutamate in a slice preparation from the mouse retina. High K stimulation induced an elevation of fluorescence in the inner plexiform layer (IPL) of the retina when glutamate transporters were inhibited bydl - threo -β-benzyloxyaspartic acid (TBOA). The high K-induced fluorescence signals in the IPL were inhibited by the calcium channel blocker Cd 2+ . Blockade of GABAergic and glycinergic circuits by picrotoxin and strychnine also elevated the fluorescence signals in the IPL. Thus, the enzyme-linked fluorescence assay system might be useful for monitoring the bulk concentration of extracellular glutamate released by synapses in the inner retina.