1
|
Keilhoff G, Titze M, Ebmeyer U. Immuno-histological detection of resistant columnar units and vulnerable networks in the rat retina after asphyxia-induced transient cardiac arrest. Restor Neurol Neurosci 2021; 39:267-289. [PMID: 34334436 DOI: 10.3233/rnn-211174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Stroke-related loss of vision is one of the residual impairments, restricting the quality of life. However, studies of the ocular manifestations of asphyxia cardiac arrest/resuscitation (ACA/R) have reported very heterogeneous results. OBJECTIVE We aimed to evaluate the ACA/R-induced degeneration pattern of the different retinal cell populations in rats using different immuno-histological stainings. METHODS The staining pattern of toluidine blue and the ganglion cell markers β-III-tubulin and NeuN; the calcium-binding protein parvalbumin, indicating ganglion, amacrine, and horizontal cells; calretinin D28k, indicating ganglion and amacrine cells; calbindin, indicating horizontal cells; Chx 10, indicating cone bipolar cells; PKCα, indicating ON-type rod bipolar cells; arrestin, indicating cones; and rhodopsin, a marker of rods, as well as the glial cell markers GFAP (indicating astroglia and Müller cells) and IBA1 (indicating microglia), were evaluated after survival times of 7 and 21 days in an ACA/R rat model. Moreover, quantitative morphological analysis of the optic nerve was performed. The ACA/R specimens were compared with those from sham-operated and completely naïve rats. RESULTS ACA/R-induced effects were: (i) a significant reduction of retinal thickness after long-term survival; (ii) ganglion cell degeneration, including their fiber network in the inner plexiform layer; (iii) degeneration of amacrine and cone bipolar cells; (iv) degeneration of cone photoreceptors; (v) enhanced resistance to ACA/R by rod photoreceptors, ON-type rod bipolar and horizontal cells, possibly caused by the strong upregulation of the calcium-binding proteins calretinin, parvalbumin, and calbindin, counteracting the detrimental calcium overload; (vi) significant activation of Müller cells as further element of retinal anti-stress self-defense mechanisms; and (vii) morphological alterations of the optic nerve in form of deformed fibers. CONCLUSIONS Regardless of the many defects, the surviving neuronal structures seemed to be able to maintain retinal functionality, which can be additionally improved by regenerative processes true to the "use it or lose it" dogma.
Collapse
Affiliation(s)
- Gerburg Keilhoff
- Institute of Biochemistry and Cell Biology, Medical Faculty, University of Magdeburg, Magdeburg, Germany
| | - Maximilian Titze
- Institute of Biochemistry and Cell Biology, Medical Faculty, University of Magdeburg, Magdeburg, Germany
| | - Uwe Ebmeyer
- Department of Anesthesiology, Medical Faculty, University of Magdeburg, Magdeburg, Germany
| |
Collapse
|
2
|
Inhibiting Matrix Metalloproteinase 3 Ameliorates Neuronal Loss in the Ganglion Cell Layer of Rats in Retinal Ischemia/Reperfusion. Neurochem Res 2016; 41:1107-18. [PMID: 26830289 DOI: 10.1007/s11064-015-1800-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/08/2015] [Accepted: 12/09/2015] [Indexed: 01/24/2023]
Abstract
It has been demonstrated that matrix metalloproteinase 3 (MMP3) is integrally involved in the neuronal degeneration of the central nervous system by promoting glial activation, neuronal apoptosis and damage to the brain-blood barrier. However, whether MMP3 also contributes to the neuronal degeneration induced by retinal ischemia/reperfusion is still uncertain. In the present study, we detected the cellular localization of MMP3 in adult rat retinae and explored the relationship of its expression with neuronal loss in the ganglion cell layer (GCL) in retinal ischemia/reperfusion. We found that MMP3 was widely expressed in many cells throughout the layers of the rat retinae, including Vertebrate neuron-specific nuclear protein (NeuN)-, parvalbumin-, calbindin-, protein kinase C-α-, glial fibrillary acidic protein-, glutamine synthetase- and CD11b-positive cells. Furthermore, all rats were treated with high intraocular pressure (HIOP) for 1 h (h) and sacrificed at 6 h, 1 day (d), 3 d, and 7 d after HIOP. Compared to the normal control, the expression of both proenzyme MMP3 and active MMP3 were significantly up-regulated after HIOP treatment without alteration of the laminar distribution pattern. Moreover, inhibiting MMP3 ameliorated the loss of NeuN-positive cells in the GCL following HIOP. In summary, our data demonstrates that MMP3 is expressed in multiple types of neurons and glial cells in normal rat retinae. Simultaneously, the up-regulation of its expression and activity are closely involved in neuronal loss in the GCL in retinal ischemia/reperfusion.
Collapse
|
3
|
Hong CJH, Siddiqui AM, Sabljic TF, Ball AK. Changes in parvalbumin immunoreactive retinal ganglion cells and amacrine cells after optic nerve injury. Exp Eye Res 2015; 145:363-372. [PMID: 26601926 DOI: 10.1016/j.exer.2015.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 10/09/2015] [Accepted: 11/04/2015] [Indexed: 11/25/2022]
Abstract
Parvalbumin (PARV) is a Ca(2+)-binding protein that may offer resistance to cell death as it primarily functions to maintain Ca(2+) homeostasis. The purpose of this study was to investigate whether PARV expressing retinal ganglion cells (RGCs) would be more resistant to cell death than RGCs that do not express PARV. RGCs in Sprague-Dawley rats were retrogradely labeled with Fluorogold (FG). After 2-28 days following an optic nerve crush (ONC) injury immunohistochemistry was performed on the sections using antibodies against PARV and markers of RGCs. The proportion of retinal ganglion cell layer cells labeled with PARV colocalized with FG or Brn3a and labeled only with PARV (displaced amacrine cells; dACs) were analyzed. PARV staining intensity was measured in ACs, dACs, and RGCs. Double labeling studies revealed that 49% of RGCs and 22% of dACs expressed PARV. There was an immediate reduction in RGC PARV staining after ONC but the overall rate of cell death after 28 days was similar in PARV and non-PARV expressing RGCs. There was no change in PARV AC or dAC number or staining intensity. Although this study suggests that there is no selective survival of the subpopulation of RGCs that contain PARV, there is down-regulation of PARV expression by these RGCs. This suggests that down-regulation of PARV may contribute to RGC death due to a compromised Ca(2+) buffering capacity. Maintaining PARV expression after injury could be an important neuroprotective strategy to improve RGC survival after injury.
Collapse
Affiliation(s)
- Chris Joon Ho Hong
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, L8N 3Z5, Canada
| | - Ahad M Siddiqui
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, L8N 3Z5, Canada
| | - Thomas F Sabljic
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, L8N 3Z5, Canada
| | - Alexander K Ball
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, L8N 3Z5, Canada.
| |
Collapse
|
4
|
Walter LT, Higa GSV, Schmeltzer C, Sousa E, Kinjo ER, Rüdiger S, Hamassaki DE, Cerchiaro G, Kihara AH. Functional regulation of neuronal nitric oxide synthase expression and activity in the rat retina. Exp Neurol 2014; 261:510-7. [PMID: 25116452 DOI: 10.1016/j.expneurol.2014.07.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/16/2014] [Accepted: 07/29/2014] [Indexed: 11/19/2022]
Abstract
In the nervous system within physiological conditions, nitric oxide (NO) production depends on the activity of nitric oxide synthases (NOSs), and particularly on the expression of the neuronal isoform (nNOS). In the sensory systems, the role of NO is poorly understood. In this study, we identified nNOS-positive cells in the inner nuclear layer (INL) of the rat retina, with distinct characteristics such as somata size, immunolabeling level and location. Employing mathematical cluster analysis, we determined that nNOS amacrine cells are formed by two distinct populations. We next investigated the molecular identity of these cells, which did not show colocalization with calbindin (CB), choline acetyltransferase (ChAT), parvalbumin (PV) or protein kinase C (PKC), and only partial colocalization with calretinin (CR), revealing the accumulation of nNOS in specific amacrine cell populations. To access the functional, circuitry-related roles of these cells, we performed experiments after adaptation to different ambient light conditions. After 24h of dark-adaptation, we detected a subtle, yet statistically significant decrease in nNOS transcript levels, which returned to steady-state levels after 24h of normal light-dark cycle, revealing that nNOS expression is governed by ambient light conditions. Employing electron paramagnetic resonance (EPR), we demonstrated that dark-adaptation decreases NO production in the retina. Furthermore, nNOS accumulation changed in the dark-adapted retinas, with a general reduction in the inner plexiform layer. Finally, computational analysis based on clustering techniques revealed that dark-adaptation differently affected both types of nNOS-positive amacrine cells. Taken together, our data disclosed functional regulation of nNOS expression and activity, disclosing new circuitry-related roles of nNOS-positive cells. More importantly, this study indicated unsuspected roles for NO in the sensory systems, particularly related to adaptation to ambient demands.
Collapse
Affiliation(s)
- Lais Takata Walter
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil
| | - Guilherme Shigueto Vilar Higa
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil; Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
| | | | - Erica Sousa
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil
| | - Erika Reime Kinjo
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil
| | - Sten Rüdiger
- Institute of Physics, Humboldt University at Berlin, Germany
| | - Dânia Emi Hamassaki
- Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
| | - Giselle Cerchiaro
- Núcleo de Cognição e Sistemas Complexos, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Brazil
| | - Alexandre Hiroaki Kihara
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil; Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil.
| |
Collapse
|
5
|
Huang JF, Shang L, Zhang MQ, Wang H, Chen D, Tong JB, Huang H, Yan XX, Zeng LP, Xiong K. Differential neuronal expression of receptor interacting protein 3 in rat retina: involvement in ischemic stress response. BMC Neurosci 2013; 14:16. [PMID: 23374330 PMCID: PMC3570281 DOI: 10.1186/1471-2202-14-16] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 01/31/2013] [Indexed: 06/29/2023] Open
Abstract
BACKGROUND Receptor-interacting protein 3 (RIP3), a member of RIP family proteins, has been shown to participate in programmed necrosis or necroptosis in cell biology studies. Evidence suggests that necroptosis may be a mode of neuronal death in the retina. RESULTS In the present study we determined the expression of RIP3 in normal rat retina and its changes following acute high intraocular pressure (aHIOP). RIP3 immunoreactivity (IR) was largely present in the inner retinal layers, localized to subsets of cells expressing neuron-specific nuclear antigen (NeuN), parvalbumin and calbindin in the ganglion cell layer (GCL) and inner nuclear layer (INL). No double labeling was detected for RIP3 with PKC-α or rhodopsin. RIP3 immunoreactivity was increased in the GCL at 6 hr and 12 hr, but reduced at 24 hr in the retina, without apparent alteration in laminar or cellular distribution pattern. Western blot analysis confirmed the above time-dependent alteration in RIP3 protein expression. RIP3 expressing cells frequently co-localized with propidium iodide (PI). A few co-localized cells were observed between RIP3 and Bax or cleaved caspase-3 in the GCL in 12 hr following aHIOP. CONCLUSIONS The results indicate that RIP3 is expressed differentially in retinal neurons in adult rats, including subsets of ganglion cells, amacrine and horizontal cells. RIP3 protein levels are elevated rapidly following aHIOP. RIP3 labeling co-localized with PI, Bax or cleaved caspase-3 among cells in the ganglion cell layer following aHIOP, which suggest its involvement of RIP3 in neuronal responses to acute ischemic insults.
Collapse
Affiliation(s)
- Ju-Fang Huang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Lei Shang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Meng-Qi Zhang
- Eight-year Clinical Medicine Program, Class 2002, Central South University Xiangya School of Medicine, Changsha, Hunan, 410013, China
| | - Hui Wang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Dan Chen
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Jian-Bin Tong
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - He Huang
- Department of Histology and Embrology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Le-Ping Zeng
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Kun Xiong
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013, China
| |
Collapse
|
6
|
Wakabayashi T, Kosaka J, Mochii M, Miki Y, Mori T, Takamori Y, Yamada H. C38, equivalent to BM88, is developmentally expressed in maturing retinal neurons and enhances neuronal maturation. J Neurochem 2009; 112:1235-48. [PMID: 20002527 DOI: 10.1111/j.1471-4159.2009.06536.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
C38 antigen is specifically expressed in neuronal cells of the retina. The purpose of this study was to isolate C38 cDNA and determine its molecular functions. Sequence analysis of C38 cDNA revealed that C38 is equivalent to rat BM88, which has been reported to induce cell-cycle arrest and neuronal differentiation in Neuro2a cells. C38 and Ki67, a marker of proliferating cells, were not colocalized during retinal development. C38 was first detected in the retinal ganglion cells at embryonic day 16, much later than the expression of doublecortin, a marker of immature neurons. Although all the horizontal cells were post-mitotic at this stage, C38 was not detected in horizontal cells until the postnatal period. In addition, C38 over-expression did not induce neuronal differentiation or cell-cycle arrest of pluripotent P19 embryonal carcinoma cells. Instead, C38 promoted maturation during neuronal differentiation of P19 embryonal carcinoma cells by down-regulating Oct-3, a pluripotent cell marker and enhancing the expressions of positive regulators of neurogenesis. In conclusion, during retinal development, C38 is first expressed in post-mitotic retinal neurons and is up-regulated during their maturation. C38 does not induce neuronal competence in pluripotent cells, but does promote maturation in already committed neuronal cells.
Collapse
Affiliation(s)
- Taketoshi Wakabayashi
- Department of Anatomy & Cell Science, Kansai Medical University, Osaka 570-8506, Japan.
| | | | | | | | | | | | | |
Collapse
|
7
|
Osswald IK, Galan A, Bowie D. Light triggers expression of philanthotoxin-insensitive Ca2+-permeable AMPA receptors in the developing rat retina. J Physiol 2007; 582:95-111. [PMID: 17430992 PMCID: PMC2075288 DOI: 10.1113/jphysiol.2007.127894] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Ca2+-permeable AMPA receptors (AMPARs) are expressed throughout the adult CNS but yet their role in development is poorly understood. In the developing retina, most investigations have focused on Ca2+ influx through NMDARs in promoting synapse maturation and not on AMPARs. However, NMDARs are absent from many retinal cells suggesting that other Ca2+-permeable glutamate receptors may be important to consider. Here we show that inhibitory horizontal and AII amacrine cells lack NMDARs but express Ca2+-permeable AMPARs. Before eye-opening, AMPARs were fully blocked by philanthotoxin (PhTX), a selective antagonist of Ca2+-permeable AMPARs. After eye-opening, however, a subpopulation of Ca2+-permeable AMPARs were unexpectedly PhTX resistant. Furthermore, Joro spider toxin (JSTX) and IEM-1460 also failed to antagonize, demonstrating that this novel pharmacology is shared by several AMPAR channel blockers. Interestingly, PhTX-insensitive AMPARs failed to express in retinae from dark-reared animals demonstrating that light entering the eye triggers their expression. Eye-opening coincides with the consolidation of inhibitory cell connections suggesting that the developmental switch to a Ca2+-permeable AMPAR with novel pharmacology may be critical to synapse maturation in the mammalian retina.
Collapse
Affiliation(s)
- Ingrid K Osswald
- Department of Pharmacology & Therapeutics, McIntyre Medical Sciences Building, Room 1317, McGill University, Montreal, Québec, Canada H3A 1Y6
| | | | | |
Collapse
|
8
|
Nakazawa A, Usuda N, Matsui T, Hanai T, Matsushita S, Arai H, Sasaki H, Higuchi S. Localization of calcineurin in the mature and developing retina. J Histochem Cytochem 2001; 49:187-95. [PMID: 11156687 DOI: 10.1177/002215540104900206] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We studied the localization of calcineurin by immunoblotting analysis and immunohistochemistry as a first step in clarifying the role of calcineurin in the retina. Rat, bovine, and human retinal tissues were examined with subtype-nonspecific and subtype-specific antibodies for the A alpha and A beta isoforms of its catalytic subunit. In mature retinas of the three species, calcineurin was localized mainly in the cell bodies of ganglion cells and the cells in the inner nuclear layer, in which amacrine cells were distinctively positive. The calcineurin A alpha and A beta isoforms were differentially localized in the nucleus and the cytoplasm of the ganglion cell, respectively. Calcineurin was also present in developing rat retinas, in which the ganglion cells were consistently positive for it. The presence of calcineurin across mammalian species and regardless of age shown in the present study may reflect its importance in visual function and retinal development, although its function in the retina has not yet been clarified. (J Histochem Cytochem 49:187-195, 2001)
Collapse
Affiliation(s)
- A Nakazawa
- Department of Anatomy II, Fujita Health University School of Medicine, Aichi, Japan
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Dyer MA, Cepko CL. p57(Kip2) regulates progenitor cell proliferation and amacrine interneuron development in the mouse retina. Development 2000; 127:3593-605. [PMID: 10903183 DOI: 10.1242/dev.127.16.3593] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A precise balance between proliferation and differentiation must be maintained during retinal development to obtain the correct proportion of each of the seven cell types found in the adult tissue. Cyclin kinase inhibitors can regulate cell cycle exit coincident with induction of differentiation programs during development. We have found that the p57(Kip2) cyclin kinase inhibitor is upregulated during G(1)/G(0) in a subset of retinal progenitor cells exiting the cell cycle between embryonic day 14.5 and 16.5 of mouse development. Retroviral mediated overexpression of p57(Kip2) in embryonic retinal progenitor cells led to premature cell cycle exit. Retinae from mice lacking p57(Kip2) exhibited inappropriate S-phase entry and apoptotic nuclei were found in the region where p57(Kip2) is normally expressed. Apoptosis precisely compensated for the inappropriate proliferation in the p57(Kip2)-deficient retinae to preserve the correct proportion of the major retinal cell types. Postnatally, p57(Kip2) was found to be expressed in a novel subpopulation of amacrine interneurons. At this stage, p57(Kip2)did not regulate proliferation. However, perhaps reflecting its role during this late stage of development, animals lacking p57(Kip2) showed an alteration in amacrine subpopulations. p57(Kip2) is the first gene to be implicated as a regulator of amacrine subtype/subpopulation development. Consequently, we propose that p57(Kip2) has two roles during retinal development, acting first as a cyclin kinase inhibitor in mitotic progenitor cells, and then playing a distinct role in neuronal differentiation.
Collapse
Affiliation(s)
- M A Dyer
- Department of Genetics and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | | |
Collapse
|
10
|
Reyes R, Lauritzen I, Lesage F, Ettaiche M, Fosset M, Lazdunski M. Immunolocalization of the arachidonic acid and mechanosensitive baseline traak potassium channel in the nervous system. Neuroscience 2000; 95:893-901. [PMID: 10670456 DOI: 10.1016/s0306-4522(99)00484-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
TRAAK is the sole member of the emerging class of 2P domain K+ channels to be exclusively expressed in neuronal cells. TRAAK produces baseline K+ currents which are strongly stimulated by arachidonic acid and by mechanical stretch, and which are insensitive to the classical K+ channel blockers tetraethylammonium, Ba2+, and Cs+. This report describes the immunolocalization of TRAAK in brain, spinal cord, and retina of the adult mouse. The most striking finding is the widespread distribution of the TRAAK immunoreactivity, with a prominent staining of the cerebellar cortex, neocortex, hippocampus, dentate gyrus, subiculum, the dorsal hippocampal commissure, thalamus, caudate-putamen, olfactory bulb, and several nuclei in the brainstem. Virtually all neurons express TRAAK, and the highest immunoreactivity was seen in soma, and to a lesser degree in axons and/or dendrites in most areas in brain and spinal cord. In the retina, the TRAAK protein is concentrated to the soma of ganglion cells and to the dendrites of all other neurons. Taken together, these results show a wide distribution of TRAAK, a mechanosensitive and arachidonic acid-stimulated neuron-specific baseline K+ channel, in brain, spinal cord and retina.
Collapse
Affiliation(s)
- R Reyes
- Institut de Pharmacologie Moléculaire et Cellulaire, UPR 411 CNRS, Valbonne, France
| | | | | | | | | | | |
Collapse
|
11
|
Abstract
The LIM/homeodomain transcription factor Lim-1 has been shown to play an essential role in early embryonic patterning during vertebrate development. Here we report the spatial and temporal expression patterns of Lim-1 during retinal development as detected by immunohistochemistry using a specific anti-Lim-1 antibody. By double-immunostaining, we have demonstrated for the first time that Lim-1 is exclusively expressed within the horizontal cell type in the adult retina. In the developing mouse retina, Lim-1 commences its expression in migratory horizontal cell precursors streaming toward the future horizontal cell layer in the ventricular zone. Moreover, its expression during retinogenesis is spatially and temporally coincident with that of the calcium-binding protein calbindin D-28k in horizontal cells. These data together suggest a possible role for Lim-1 in terminal differentiation and maintenance of horizontal cells, and that Lim-1 can serve as a specific molecular marker for the study of horizontal cell specification.
Collapse
Affiliation(s)
- W Liu
- Graduate Program in Microbiology and Molecular Genetics, UMDNJ-Robert Wood Johnson Medical School, Center for Advanced Biotechnology and Medicine, Piscataway, New Jersey 08854, USA
| | | | | |
Collapse
|