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Liu H, Schaeffel F, Yang Z, Feldkaemper MP. GABAB Receptor Activation Affects Eye Growth in Chickens with Visually Induced Refractive Errors. Biomolecules 2023; 13:biom13030434. [PMID: 36979369 PMCID: PMC10046083 DOI: 10.3390/biom13030434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/08/2023] [Accepted: 02/13/2023] [Indexed: 03/02/2023] Open
Abstract
This study aims to explore the role of GABAB receptors in the development of deprivation myopia (DM), lens-induced myopia (LIM) and lens-induced hyperopia (LIH). Chicks were intravitreally injected with 25 µg baclofen (GABABR agonist) in one eye and saline into the fellow eye. Choroidal thickness (ChT) was measured via OCT before and 2, 4, 6, 8, 24 h after injection. ChT decreased strongly at 6 and 8 h after baclofen injection and returned back to baseline level after 24 h. Moreover, chicks were monocularly treated with translucent diffusers, −7D or +7D lenses and randomly assigned to baclofen or saline treatment. DM chicks were injected daily into both eyes, while LIM and LIH chicks were monocularly injected into the lens-wearing eyes, for 4 days. Refractive error, axial length and ChT were measured before and after treatment. Dopamine and its metabolites were analyzed via HPLC. Baclofen significantly reduced the myopic shift and eye growth in DM and LIM eyes. However, it did not change ChT compared to respective saline-injected eyes. On the other hand, baclofen inhibited the hyperopic shift and choroidal thickening in LIH eyes. All the baclofen-injected eyes showed significantly lower vitreal DOPAC content. Since GABA is an inhibitory ubiquitous neurotransmitter, interfering with its signaling affects spatial retinal processing and therefore refractive error development with both diffusers and lenses.
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Affiliation(s)
- Hong Liu
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, 72076 Tuebingen, Germany
- Aier Institute of Optometry and Vision Science, Aier Eye Hospital Group, Changsha 410000, China
| | - Frank Schaeffel
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, 72076 Tuebingen, Germany
- Myopia Research Group, Institute of Molecular and Clinical Ophthalmology Basel (IOB), 4031 Basel, Switzerland
| | - Zhikuan Yang
- Aier Institute of Optometry and Vision Science, Aier Eye Hospital Group, Changsha 410000, China
- Hunan Province Optometry Engineering and Technology Research Center, Changsha 410000, China
- Hunan Province International Cooperation Base for Optometry Science and Technology, Changsha 410000, China
- Correspondence: (Z.Y.); (M.P.F.)
| | - Marita Pauline Feldkaemper
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, 72076 Tuebingen, Germany
- Correspondence: (Z.Y.); (M.P.F.)
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Huang Y, Chen X, Zhuang J, Yu K. The Role of Retinal Dysfunction in Myopia Development. Cell Mol Neurobiol 2022:10.1007/s10571-022-01309-1. [DOI: 10.1007/s10571-022-01309-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 11/16/2022] [Indexed: 11/27/2022]
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Fasoli A, Dang J, Johnson JS, Gouw AH, Fogli Iseppe A, Ishida AT. Somatic and neuritic spines on tyrosine hydroxylase-immunopositive cells of rat retina. J Comp Neurol 2017; 525:1707-1730. [PMID: 28035673 DOI: 10.1002/cne.24166] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 12/13/2016] [Accepted: 12/27/2016] [Indexed: 12/27/2022]
Abstract
Dopamine- and tyrosine hydroxylase-immunopositive cells (TH cells) modulate visually driven signals as they flow through retinal photoreceptor, bipolar, and ganglion cells. Previous studies suggested that TH cells release dopamine from varicose axons arborizing in the inner and outer plexiform layers after glutamatergic synapses depolarize TH cell dendrites in the inner plexiform layer and these depolarizations propagate to the varicosities. Although it has been proposed that these excitatory synapses are formed onto appendages resembling dendritic spines, spines have not been found on TH cells of most species examined to date or on TH cell somata that release dopamine when exposed to glutamate receptor agonists. By use of protocols that preserve proximal retinal neuron morphology, we have examined the shape, distribution, and synapse-related immunoreactivity of adult rat TH cells. We report here that TH cell somata, tapering and varicose inner plexiform layer neurites, and varicose outer plexiform layer neurites all bear spines, that some of these spines are immunopositive for glutamate receptor and postsynaptic density proteins (viz., GluR1, GluR4, NR1, PSD-95, and PSD-93), that TH cell somata and tapering neurites are also immunopositive for a γ-aminobutyric acid (GABA) receptor subunit (GABAA Rα1 ), and that a synaptic ribbon-specific protein (RIBEYE) is found adjacent to some colocalizations of GluR1 and TH in the inner plexiform layer. These results identify previously undescribed sites at which glutamatergic and GABAergic inputs may stimulate and inhibit dopamine release, especially at somata and along varicose neurites that emerge from these somata and arborize in various levels of the retina. J. Comp. Neurol. 525:1707-1730, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Anna Fasoli
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
| | - James Dang
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
| | - Jeffrey S Johnson
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
| | - Aaron H Gouw
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
| | - Alex Fogli Iseppe
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
| | - Andrew T Ishida
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California.,Department of Ophthalmology and Vision Science, University of California, Sacramento, California
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Barathi VA, Chaurasia SS, Poidinger M, Koh SK, Tian D, Ho C, Iuvone PM, Beuerman RW, Zhou L. Involvement of GABA transporters in atropine-treated myopic retina as revealed by iTRAQ quantitative proteomics. J Proteome Res 2014; 13:4647-58. [PMID: 25211393 PMCID: PMC4227558 DOI: 10.1021/pr500558y] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Atropine,
a muscarinic antagonist, is known to inhibit myopia progression
in several animal models and humans. However, the mode of action is
not established yet. In this study, we compared quantitative iTRAQ
proteomic analysis in the retinas collected from control and lens-induced
myopic (LIM) mouse eyes treated with atropine. The myopic group received
a (−15D) spectacle lens over the right eye on postnatal day
10 with or without atropine eye drops starting on postnatal day 24.
Axial length was measured by optical low coherence interferometry
(OLCI), AC-Master, and refraction was measured by automated infrared
photorefractor at postnatal 24, 38, and 52 days. Retinal tissue samples
were pooled from six eyes for each group. The experiments were repeated
twice, and technical replicates were also performed for liquid chromatography–tandem
mass spectrometry (LC–MS/MS) analysis. MetaCore was used to
perform protein profiling for pathway analysis. We identified a total
of 3882 unique proteins with <1% FDR by analyzing the samples in
replicates for two independent experiments. This is the largest number
of mouse retina proteome reported to date. Thirty proteins were found
to be up-regulated (ratio for myopia/control > global mean ratio
+
1 standard deviation), and 28 proteins were down-regulated (ratio
for myopia/control < global mean ratio - 1 standard deviation)
in myopic eyes as compared with control retinas. Pathway analysis
using MetaCore revealed regulation of γ-aminobutyric acid (GABA)
levels in the myopic eyes. Detailed analysis of the quantitative proteomics
data showed that the levels of GABA transporter 1 (GAT-1) were elevated
in myopic retina and significantly reduced after atropine treatment.
These results were further validated with immunohistochemistry and
Western blot analysis. In conclusion, this study provides a comprehensive
quantitative proteomic analysis of atropine-treated mouse retina and
suggests the involvement of GABAergic signaling in the antimyopic
effects of atropine in mouse eyes. The GABAergic transmission in the
neural retina plays a pivotal role in the maintenance of axial eye
growth in mammals.
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Affiliation(s)
- Veluchamy A Barathi
- Singapore Eye Research Institute , 11 Third Hospital Avenue, Singapore 168751, Singapore
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Stone RA, McGlinn AM, Baldwin DA, Tobias JW, Iuvone PM, Khurana TS. Image defocus and altered retinal gene expression in chick: clues to the pathogenesis of ametropia. Invest Ophthalmol Vis Sci 2011; 52:5765-77. [PMID: 21642623 DOI: 10.1167/iovs.10-6727] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
PURPOSE Because of the retina's role in refractive development, this study was conducted to analyze the retinal transcriptome in chicks wearing a spectacle lens, a well-established means of inducing refractive errors, to identify gene expression alterations and to develop novel mechanistic hypotheses about refractive development. METHODS One-week-old white Leghorn chicks wore a unilateral spectacle lens of +15 or -15 D for 6 hours or 3 days. With total RNA from the retina/(retinal pigment epithelium, RPE), chicken gene microarrays were used to compare gene expression levels between lens-wearing and contralateral control eyes (n = 6 chicks for each condition). Normalized microarray signal intensities were evaluated by analysis of variance, using a false discovery rate of <10% as the statistical criterion. Selected differentially expressed genes were validated by qPCR. RESULTS Very few retina/RPE transcripts were differentially expressed after plus lens wear. In contrast, approximately 1300 transcripts were differentially expressed under each of the minus lens conditions, with minimal overlap. For each condition, low fold-changes typified the altered transcriptome. Differentially regulated genes under the minus lens conditions included many potentially informative signaling molecules and genes whose protein products have roles in intrinsic retinal circadian rhythms. CONCLUSIONS Plus or minus lens wear induce markedly different, not opposite, alterations in retina/RPE gene expression. The initial retinal responses to defocus are quite different from those when the eye growth patterns are well established, suggesting that different mechanisms govern the initiation and persistence or progression of refractive errors. The gene lists identify promising signaling candidates and regulatory pathways for future study, including a potential role for circadian rhythms in refractive development.
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Affiliation(s)
- Richard A Stone
- Department of Ophthalmology, University of Pennsylvania School of Medicine, Scheie Eye Institute, Philadelphia, Pennsylvania 19104-6075, USA.
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Danilenko KV, Plisov IL, Wirz‐Justice A, Hébert M. Human Retinal Light Sensitivity and Melatonin Rhythms Following Four Days in Near Darkness. Chronobiol Int 2009; 26:93-107. [DOI: 10.1080/07420520802689814] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Mills SL, Xia XB, Hoshi H, Firth SI, Rice ME, Frishman LJ, Marshak DW. Dopaminergic modulation of tracer coupling in a ganglion-amacrine cell network. Vis Neurosci 2007; 24:593-608. [PMID: 17711603 PMCID: PMC2213423 DOI: 10.1017/s0952523807070575] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Accepted: 06/12/2007] [Indexed: 11/06/2022]
Abstract
Many retinal ganglion cells are coupled via gap junctions with neighboring amacrine cells and ganglion cells. We investigated the extent and dynamics of coupling in one such network, the OFF alpha ganglion cell of rabbit retina and its associated amacrine cells. We also observed the relative spread of Neurobiotin injected into a ganglion cell in the presence of modulators of gap junctional permeability. We found that gap junctions between amacrine cells were closed via stimulation of a D(1) dopamine receptor, while the gap junctions between ganglion cells were closed via stimulation of a D(2) dopamine receptor. The pairs of hemichannels making up the heterologous gap junctions between the ganglion and amacrine cells were modulated independently, so that elevations of cAMP in the ganglion cell open the ganglion cell hemichannels, while elevations of cAMP in the amacrine cell close its hemichannels. We also measured endogenous dopamine release from an eyecup preparation and found a basal release from the dark-adapted retina of approximately 2 pmol/min during the day. Maximal stimulation with light increased the rate of dopamine release from rabbit retina by 66%. The results suggest that coupling between members of the OFF alpha ganglion cell/amacrine cell network is differentially modulated with changing levels of dopamine.
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Affiliation(s)
- Stephen L Mills
- Department of Ophthalmology and Visual Science, University of Texas at Houston-Health Science Center, Houston, Texas 77030, USA.
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Asay MJ, Boyd SK. Characterization of the binding of [3H]CGP54626 to GABAB receptors in the male bullfrog (Rana catesbeiana). Brain Res 2006; 1094:76-85. [PMID: 16725130 DOI: 10.1016/j.brainres.2006.03.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2005] [Revised: 03/06/2006] [Accepted: 03/07/2006] [Indexed: 10/24/2022]
Abstract
Gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the vertebrate brain. GABA activates both ionotropic (GABA(A)) and metabotropic (GABA(B)) receptors in mammals. Whether non-mammalian vertebrates possess receptors with similar characteristics is not well understood. We used a mammalian GABA(B)-specific antagonist to determine the pharmacology of putative receptors in the brain of an anuran amphibian, the male bullfrog (Rana catesbeiana). Receptor binding assays with the antagonist [(3)H]CGP54626 revealed a single class of high affinity binding sites (with a K(D) of 2.97 nM and a B(max) of 2619 fmol/mg protein). Binding was time- and temperature-dependent, saturable and specific. Specific binding of [(3)H]CGP54626 was inhibited by several mammalian GABA(B) receptor agonists and antagonists. The rank order potency of agonists was: GABA = SKF97541 > (R)-Baclofen > 3-APPA. The rank order for antagonists was: CGP54626 = CGP55845 > CGP52432 > CGP35348. The GABA(A) receptor ligands muscimol and SR95531 had very low affinity for [(3)H]CGP54626 binding sites, while bicuculline compounds had no affinity. Binding of GABA was positively modulated by CGP7930. Taurine did not allosterically modulate GABA binding but did inhibit [(3)H]CGP54626 binding in a linear fashion. Bullfrog brain thus possesses binding sites with significant similarity to mammalian GABA(B) receptors. These receptors differ from mammalian receptors, however, in dissociation kinetics, ligand specificity and allosteric modulation.
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Affiliation(s)
- Matthew J Asay
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.
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Harada Y, Sanada K, Fukada Y. Circadian activation of bullfrog retinal mitogen-activated protein kinase associates with oscillator function. J Biol Chem 2000; 275:37078-85. [PMID: 10978323 DOI: 10.1074/jbc.m004706200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The vertebrate retina retains a circadian oscillator, and its oscillation is self-sustained with a period close to 24 h under constant environmental conditions. Here we show that bullfrog retinal mitogen-activated protein kinase (MAPK) exhibits an in vivo circadian rhythm in phosphorylation with a peak at night in a light/dark cycle. The phosphorylation rhythm of MAPK persists in constant darkness with a peak at subjective night, and this self-sustained rhythm is also observed in cultured retinas, indicating its close interaction with the retinal oscillator. The rhythmically phosphorylated MAPK is detected only in a discrete subset of amacrine cells despite ubiquitous distribution of MAPK throughout the retinal layers. Treatment of the cultured retinas with MAPK kinase (MEK) inhibitor PD98059 suppresses MAPK phosphorylation during the subjective night, and this pulse perturbation of MEK activity induces a significant phase delay (4-8 h) of the retinal circadian rhythm in MAPK and MEK phosphorylation. These observations strongly suggest that the site-specific and time-of-day-specific activation of MAPK contributes to the circadian time-keeping mechanism of the retinal clock system.
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Affiliation(s)
- Y Harada
- Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo and CREST, Japan Science and Technology Corporation, Tokyo 113-0033, Japan
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Adachi A, Nogi T, Ebihara S. Phase-relationship and mutual effects between circadian rhythms of ocular melatonin and dopamine in the pigeon. Brain Res 1998; 792:361-9. [PMID: 9593995 DOI: 10.1016/s0006-8993(98)00206-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In order to study the mechanisms of ocular circadian rhythms in the pigeon, we measured melatonin and dopamine simultaneously from the eye using in vivo microdialysis. In experiment 1, the phase relationship between circadian rhythms of ocular melatonin and dopamine under light-dark cycles (LD) and continuous dim light (LLdim) was examined. Under LD, melatonin was high during the dark and low during the light. On the other hand dopamine was high during the light and low during the dark. These rhythms with the anti-phase relationship were maintained after the birds were transferred from LD to LLdim. In experiment 2, effects of a single light pulse on melatonin and dopamine rhythms were examined. A light pulse at CT18 rapidly suppressed melatonin release to the daytime level, whereas it rapidly increased dopamine release to the daytime level. The light pulse also affected the phases of melatonin and dopamine rhythms, inducing phase advances of both rhythm without changing the anti-phase relationship before the light pulse. In experiment 3, effects of an intraocular injection of dopamine or melatonin on their circadian rhythms were examined. A dopamine injection during the subjective night suppressed melatonin release and induced a light-pulse type phase shift in both melatonin and dopamine rhythms. On the other hand, a melatonin injection during the subjective day suppressed dopamine release and induced a dark-pulse type phase shift. These results are compatible with either one or two oscillator models, but the interaction between melatonin and dopamine is, in either case considered as an important mechanism regulating ocular circadian rhythms of the pigeon.
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Affiliation(s)
- A Adachi
- Department of Animal Physiology, School of Agricultural Sciences, Nagoya University, Chikusa, Nagoya 464-01, Japan
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Gustincich S, Feigenspan A, Wu DK, Koopman LJ, Raviola E. Control of dopamine release in the retina: a transgenic approach to neural networks. Neuron 1997; 18:723-36. [PMID: 9182798 DOI: 10.1016/s0896-6273(00)80313-x] [Citation(s) in RCA: 173] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Dopaminergic, interplexiform amacrines (DA cells) were labeled in transgenic mice with human placental alkaline phosphatase, an enzyme that resides on the outer surface of the cell membrane. It was therefore possible to investigate their activity in vitro after dissociation of the retina with whole-cell current and voltage clamp, as well as their connections in the intact retina with the electron microscope. DA cells generate action potentials even in the absence of synaptic inputs. This activity is abolished by the amacrine cell transmitters GABA and glycine, which induce an inward current carried by chloride ions, and is stimulated by kainate, an agonist at the receptor for the bipolar cell transmitter glutamate, which opens nonselective cation channels. Since DA cells are postsynaptic to amacrine and bipolar cells, we suggest that the spontaneous discharge of DA cells is inhibited in the dark by GABAergic amacrines that receive their input from off-bipolars. Upon illumination, the GABA-inhibition is removed, DA cells generate action potentials, and their firing is modulated by the excitation received from on-bipolars.
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Affiliation(s)
- S Gustincich
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA
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Boatright JH, Rubim NM, Iuvone PM. Regulation of endogenous dopamine release in amphibian retina by melatonin: the role of GABA. Vis Neurosci 1994; 11:1013-8. [PMID: 7947394 DOI: 10.1017/s0952523800003941] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In the retina of the African clawed frog (Xenopus laevis), endogenous dopamine release increases in light and decreases in darkness. Exogenous melatonin and several chemical analogs of melatonin suppressed light-evoked dopamine release from frog retina in a concentration-dependent manner. The rank order of potency for inhibition of light-evoked dopamine release was melatonin >> 5-methoxytryptamine > or = N-acetylserotonin > 5-methoxytryptophol >>> serotonin. Melatonin did not suppress dopamine release below levels seen in darkness. The putative melatonin receptor antagonist luzindole inhibited the effect of melatonin. Luzindole enhanced dopamine release in darkness but had little effect in light. These data suggest a role for endogenous melatonin in dark-induced suppression of retinal dopamine. Picrotoxin and bicuculline, GABA-A receptor antagonists, blocked melatonin-induced suppression of dopamine release. In the presence of melatonin, bicuculline was significantly less potent in stimulating dopamine release. These results suggest that melatonin enhances GABAergic inhibition of light-evoked dopamine release. This mechanism may underlie the light/dark difference in dopamine release in vertebrate retina.
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Affiliation(s)
- J H Boatright
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322-3090
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Boatright JH, Gordon JR, Iuvone PM. Inhibition of endogenous dopamine release in amphibian retina by L-2-amino-4-phosphonobutyric acid (L-AP4) and trans-2-aminocyclopentane-1,3-dicarboxylate (ACPD). Brain Res 1994; 649:339-42. [PMID: 7525012 DOI: 10.1016/0006-8993(94)91084-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The metabotropic glutamate receptor agonists 2-amino-4-phosphonobutyric acid (AP4) and trans-2-aminocyclopentane-1,3-dicarboxylate (ACPD) blocked light-stimulated dopamine release from Xenopus laevis retina. ACPD suppressed release in darkness but AP4 did not. AP4 blocked release stimulated in darkness by picrotoxin, a GABA-A receptor antagonist. The data suggest that regulation of dopamine release in Xenopus retina involves subpopulations of metabotropic glutamate receptors.
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Affiliation(s)
- J H Boatright
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322-3090
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