Neuroprotektion und Regeneration nach Durchtrennung des Sehnervs

Zusammenfassung

Hintergrund: Nach einer traumatischen Läsion des Sehnervs kommt es zu einer progressiven Degeneration von retinalen Ganglienzellen (RGZ) durch Apoptose und damit einem Verlust der Sehfähigkeit des betroffenen Auges. Wie auch andere Neurone des zentralen Nervensystems können die RGZ ihre geschädigten Axone nicht spontan regenerieren. Wir setzten spezielle chirurgische und pharmakologische Methoden ein, um das Überleben der RGZ und die Regeneration ihrer Axone zu erreichen. Material und Methoden: Die Untersuchungen fanden am Modell der Degeneration der RGZ nach einer Schädigung des Sehnervs der adulten Ratte statt. Die RGZ wurden mit einem Fluoreszenzfarbstoff beladen und verschiedene Substanzen wurden intravitreal appliziert. Nach zwei Wochen wurden die Effekte anhand der Anzahl der überlebenden RGZ quantifiziert. Für die Untersuchungen zur Regeneration wurde an den Stumpf des Sehnervs ein autologes peripheres Transplantat angenäht oder die beiden Enden des durchtrennten Sehnervs wurden wieder zusammengenäht. Die Wiederherstellung der Funktion der RGZ wurde mittels VEP-Messungen untersucht. Ergebnisse: Die Anzahl der eine Axotomie überlebenden RGZ stieg signifikant nach intravitrealen Injektionen von Aurintricarboxylsäure, Cortisol, eines Caspase-Hemmers, Brimonidin oder Mikroglia-gerichteter Substanzen an. Die Regeneration der durchtrennten Axone konnte durch Aurintricarboxylsäure oder Cortisol verstärkt werden. Erhebliche neuroprotektive und regenerative Effekte einschließlich einer partiellen Wiederherstellung des VEP konnten durch die Induktion einer Linsenverletzung, welche zu einer allmählichen Freisetzung von Kristallinen in den Glaskörper führt, oder durch die intravitreale Injektion von aufgereinigten Kristallinen erreicht werden. Schlussfolgerung: Durch geeignete neuroprotektive Maßnahmen kann der bislang unvermeidliche Verlust der Sehfähigkeit nach einem Sehnervtrauma im Tiermodell verhindert werden, was die Entwicklung von Behandlungsmethoden für Patienten hoffnungsvoll erscheinen lässt.

Abstract

Background: After a traumatic lesion of the optic nerve, retinal ganglion cells (RGC) undergo massive degeneration by apoptosis, which leads to loss of vision in the affected eye. Like other neurones in the central nervous system, RGC are not able to regenerate their damaged axons spontaneously. We used special surgical methods and pharmacological measures to achieve enhanced survival and regeneration of damaged RGC. Materials and Methods: Studies were performed using the model of RGC degeneration induced by severing the optic nerve of adult rats. RGC were loaded with a fluorescent dye, and several drugs were applied intravitreally. The effects were evaluated after two weeks by counting the surviving RGC. For regeneration studies, an autologous peripheral nerve graft was sutured to the stump of the cut optic nerve, or the ends of the cut optic nerve were re-sutured. Recovery of RGC function was assessed by VEP measurements. Results: The number of RGC surviving an axotomy increased significantly after intravitreal injections of aurintricarboxylic acid, cortisol, a caspase inhibitor, brimonidine or microglia-targeted substances. Regeneration of cut axons was enhanced by aurintricarboxylic acid or cortisol. In addition, considerable neuroprotective and regenerative effects including partial restoration of VEP were induced by lens injury, which results in a gradual release of crystallins into the vitreous, or by intravitreal injection of purified crystallins. Conclusion: The loss of vision after an optic nerve trauma can be reduced in this animal model by suitable neuroprotective measures, which raises hope for the treatment of patients.

Schlüsselwörter

Retinale Ganglienzellen - Trauma - Sehnerv - Apoptose - Neuroprotektion - Regeneration - Aurintricarboxylsäure - Linsenverletzung - Kristallin - VEP

Key words

Retinal ganglion cells - trauma - optic nerve - apoptosis - neuroprotection - regeneration - aurintricarboxylic acid - lens injury - crystallin - VEP

Literatur

• 1 Adayev T, Estephan R, Meserole S. et al . Externalization of phosphatidylserine may not be an early signal of apoptosis in neuronal cells, but only the phosphatidylserine-displaying apoptotic cells are phagocytosed by microglia.  J Neurochem. 1998;  71 1854-1864
• 2 Ahmann P. In vitro Studie zur neurotrophen Wirkung des Augenlinsen-Proteins BetaH-Kristallin auf Motoneurone des embryonalen Hühnchens (Gallus gallus). Dissertation. Bremen; Universität Bremen 2003
• 3 Ahmed F A, Hegazy K, Chaudhary P. et al . Neuroprotective effect of (2 agonist (brimonidine) on adult rat retinal ganglion cells after increased intraocular pressure.  Brain Res. 2001;  913 133-139
• 4 Aitken P, Sofferman R. Traumatic optic neuropathy.  Ophthalmol. Clin. North Am. 1991;  4 479-490
• 5 Akiyama H, Kawamata T, Dedhar S. et al . Immunohistochemical localization of vitronectin, its receptor and beta-3 in Alzheimer brain tissue.  J Neuroimmunol. 1991;  32 19-28
• 6 Bähr M, Vanselow J, Thanos S. In vitro regeneration of adult rat ganglion cell axons from retinal explants.  Exp Brain Res. 1988;  73 393-401
• 7 Barron K D. The microglial cell. A historical review.  J. Neurol Sci. 1995;  134 (Suppl) 57-68
• 8 Berdan R C, Easaw J C, Wang R. Alterations in membrane potential after axotomy at different distances from the soma of an identified neuron and the effect of depolarization on neurite outgrowth and calcium channel expression.  J Neurophysiol. 1993;  69 151-164
• 9 Berkelaar M, Clarke D B, Wang Y C. et al . Axotomy results in delayed death and apoptosis of retinal ganglion cells in adult rats.  J Neurosci. 1994;  14 4368-4374
• 10 Berry M, Carlile J, Hunter A. Peripheral nerve explants grafted into the vitreous body of the eye promote the regeneration of retinal ganglion cell axons severed in the optic nerve.  J Neurocytol. 1996;  25 147-170
• 11 Berry M, Carlile J, Hunter A. et al . Optic nerve regeneration after intravitreal peripheral nerve implants: trajectories of axons regrowing through the optic chiasm into the optic tracts.  J Neurocytol. 1999;  28 721-741
• 12 Bracken M B, Shepard M J, Collins W F. et al . A randomized, controlled trial of methylprednisolone or naloxone in the treatment of acute spinal-cord injury. Results of the Second National Acute Spinal Cord Injury Study.  N. Engl. J Med. 1990;  322 1405-1411
• 13 Bracken M B, Shepard M J, Holford T R. et al . Administration of methylprednisolone for 24 or 48 hours or tirilazad mesylate for 48 hours in the treatment of acute spinal cord injury. Results of the Third National Acute Spinal Cord Injury Randomized Controlled Trial. National Acute Spinal Cord Injury Study.  JAMA. 1997;  277 1597-1604
• 14 Burke J, Schwartz M. Preclinical evaluation of brimonidine.  Surv Ophthalmol. 1996;  41 (Suppl 1) 9-18
• 15 Campbell G, Holt J K, Shotton H R. et al . Spontaneous axonal regeneration after optic nerve injury in adult rat.  NeuroReport. 1999;  10 3955-3960
• 16 Cantor L B. The evolving pharmacotherapeutic profile of brimonidine, an alpha 2-adrenergic agonist, after four years of continuous use. Expert Opin.  Pharmacother. 2000;  1 815-834
• 17 Carri N G, Richardson P, Ebendal T. Choroid coat extract and ciliary neurotrophic factor strongly promote neurite outgrowth in the embryonic chick retina.  Int J Dev Neurosci. 1994;  12 567-578
• 18 Chao D T, Korsmeyer S T. BCL-2 FAMILY: Regulators of cell death.  Annu. Rev. Immunol. 1998;  16 395-419
• 19 Chaudhary P, Ahmed F, Quebada P. et al . Caspase inhibitors block the retinal ganglion cell death following optic nerve transection.  Brain Res Mol Brain Res. 1999;  67 36-45
• 20 Chen D F, Schneider G E, Martinou J C. et al . Bcl-2 promotes regeneration of severed axons in mammalian CNS.  Nature. 1997;  385 434-439
• 21 Cheung Z H, Yip H K, Wu W. et al . Axotomy induces cytochrome c release in retinal ganglion cells.  Neuroreport. 2003;  14 279-282
• 22 Cohen G M. Caspases: the executioners of apoptosis.  Biochem J. 1997;  326 1-16
• 23 Coleman W P, Benzel D, Cahill D W. et al . A critical appraisal of the reporting of the National Acute Spinal Cord Injury Studies (II and III) of methylprednisolone in acute spinal cord injury.  J Spinal Disord. 2000;  13 185-199
• 24 Colton C A, Chernyshev O N. Inhibition of microglial superoxide anion production by isoproterenol and dexamethasone.  Neurochem Int. 1996;  29 43-53
• 25 Cui Q, Harvey A R. CNTF promotes the regrowth of retinal ganglion cell axons into murine peripheral nerve grafts.  NeuroReport. 2000;  11 3999-4002
• 26 Cui Q, Lu Q, So K F. et al . CNTF, not other trophic factors, promotes axonal regeneration of axotomized retinal ganglion cells in adult hamsters.  Invest Ophthalmol Vis Sci. 1999;  40 760-766
• 27 Davies S J, Field P M, Raisman G. Long interfascicular axon growth from embryonic neurones transplanted into adult myelinated tracts.  J Neurosci. 1994;  14 1596-1612
• 28 Davies S J, Fitch M T, Memberg S P. et al . Regeneration of adult axons in white matter tracts of the central nervous system.  Nature. 1997;  390 680-683
• 29 Dezawa M, Adachi-Usami E. Role of Schwann cells in retinal ganglion cell axon regeneration.  Progr Ret Eye Res. 2000;  19 171-204
• 30 Donello J E, Padillo E U, Webster M L. et al . α2-Adrenoceptor agonists inhibit vitreal glutamate and aspartate accumulation and preserve retinal function after transient ischemia.  J Pharmacol Exp Ther. 2001;  296 216-223
• 31 Drew P D, Chavis J A. Inhibition of microglial cell activation by cortisol.  Brain Res Bull. 2000;  52 391-396
• 32 D’Souza S E, Ginsberg M H, Plow E F. Arginyl-glycyl-aspartic acid (RGD): a cell adhesion motif.  Trends Biochem Sci. 1991;  16 246-250
• 33 Dubreuil C I, Winton M J, McKerracher L. Rho activation patterns after spinal cord injury and the role of activated Rho in apoptosis in the central nervous system.  J Cell Biol. 2003;  162 233-243
• 34 Fadok V A, Bratton D L, Frasch S C. et al . The role of phosphatidylserine in recognition of apoptotic cells by phagocytes.  Cell Death Differ. 1998;  5 551-562
• 35 Fadok V A, Voelker D R, Campbell P A. et al . Exposure of phosphatidylserine on the surface of apoptotic lymphocytes triggers specific recognition and removal by macrophages.  J Immunol. 1992;  148 2207-2216
• 36 Fan J, Mansfield S G, Redmond T. et al . The organization of F-actin and microtubules in growth cones exposed to a brain-derived collapsing factor.  J Cell Biol. 1993;  121 867-878
• 37 Farkas R H, Grosskreutz C L. Apoptosis, neuroprotection, and retinal ganglion cell death: An overview.  Int Ophthalmol Clin. 2001;  41 111-130
• 38 Fischer D. Protektiver Einfluß von β- und γ-Kristallinen auf das neuronale Überleben und die axonale Regeneration im adulten Zentralen Nervensystem. Dissertation. Marburg; Universität Marburg 2000
• 39 Fischer D, Heiduschka P, Thanos S. Lens-injury stimulated axonal regeneration throughout the optic pathway of adult rats.  Exp Neurol. 2001;  172 257-272
• 40 Fischer D, Pavlidis M, Thanos S. Cataractogenic lens injury prevents traumatic ganglion cell death and promotes axonal regeneration both in vivo and in culture.  2000;  41 3943-3954
• 41 Ford-Holevinski T S, Hopkins J M, McCoy J P. et al . Laminin supports neurite outgrowth from explants of axotomized adult rat retinal neurons.  Brain Res. 1986;  393 121-126
• 42 Fournier A E, McKerracher L. Expression of specific tubulin isotypes increases during regeneration of injured CNS neurones, but not after the application of brain-derived neurotrophic factor (BDNF).  J Neurosci. 1997;  17 4623-4632
• 43 Freeman E E, Grosskreutz C L. The effects of FK506 on retinal ganglion cells after optic nerve crush.  Invest Ophthalmol Vis Sci. 2000;  41 1111-1115
• 44 Garcia-Valenzuela E, Gorczyca W, Darzynkiewicz Z. et al . Apoptosis in adult retinal ganglion cells after axotomy.  J Neurobiol. 1994;  25 431-438
• 45 Gellrich N C. Kontroversen und aktueller Stand der Therapie von Sehnervschäden in der kraniofazialen Traumatologie und Chirurgie.  Mund Kiefer GesichtsChir. 1999;  3 176-194
• 46 Girotto J A, Gamble W B, Robertson B. et al . Blindness after reduction of facial fractures.  Plast Reconstr Surg. 1998;  102 1821-1834
• 47 Green D R. Apoptotic pathways: the roads to ruin.  Cell. 1998;  94 695-698
• 48 Hallick R B, Chelm B K, Gray P W. et al . Use of aurintricarboxylic acid as an inhibitor of nucleases during nucleic acid isolation.  Nucleic Acids Res. 1977;  4 3055-3064
• 49 Heiduschka P, Thanos S. Aurintricarboxylic acid promotes survival and regeneration of axotomised retinal ganglion cells in vivo.  Neuropharmacology. 2000;  39 889-902
• 50 Heiduschka P, Thanos S. Restoration of the retinofugal pathway.  Progr Ret Eye Res. 2000;  19 577-606
• 51 Hugenholtz H, Cass D E, Dvorak M F. et al . High-dose methylprednisolone for acute closed spinal cord injury: only a treatment option.  Can J Neurol Sci. 2002;  29 227-235
• 52 Hülsmann S, Greiner C, Köhling R. et al . Dimethyl sulfoxide increases latency of anoxic terminal negativity in hippocampal slices of guinea pig in vitro.  Neurosci Lett. 1999;  261 1-4
• 53 Isenmann S, Kretz A, Cellerino A. Molecular determinants of retinal ganglion cell development, survival, and regeneration.  Progr Ret Eye Res. 2003;  22 483-543
• 54 Isenmann S, Wahl C, Krajewski S. et al . Up-regulation of Bax protein in degenerating retinal ganglion cells precedes apoptotic cell death after optic nerve lesion in the rat.  Eur J Neurosci. 1997;  9 1763-1772
• 55 Jo S A, Wang E, Benowitz L I. Ciliary neurotrophic factor is an axogenesis factor for retinal ganglion cells.  Neuroscience. 1999;  89 579-591
• 56 Joo C K, Choi J S, Ko H W. et al . Necrosis and apoptosis after retinal ischemia: involvement of NMDA-mediated excitotoxicity and p53.  Invest Ophthalmol Vis Sci. 1999;  40 713-720
• 57 Jun C D, Hoon R yu, Um J Y. et al . Involvement of protein kinase C in the inhibition of nitric oxide production from murine microglial cells by glucocorticoid.  Biochem Biophys Res Commun. 1994;  199 633-638
• 58 Kashii S, Mandai M, Kikuchi M. et al . Dual actions of nitric oxide in N-methyl-D-aspartate receptor-mediated neurotoxicity in cultured retinal neurons.  Brain Res. 1996;  711 93-101
• 59 Keirstead S A, Rasminsky M, Fukuda Y. et al . Electrophysiologic responses in hamster superior colliculus evoked by regenerating retinal axons.  Science. 1989;  246 255-257
• 60 Kermer P, Ankerhold R, Klöcker N. et al . Caspase-9: involvement in secondary death of axotomized rat retinal ganglion cells in vivo.  Brain Res Mol Brain Res. 2000;  85 144-150
• 61 Kermer P, Klöcker N, Labes M. et al . Inhibition of CPP32-like proteases rescues axotomized retinal ganglion cells from secondary cell death in vivo.  J Neurosci. 1998;  18 4656-4662
• 62 Kermer P, Klöcker N, Labes M. et al . Activation of caspase-3 in axotomized rat retinal ganglion cells in vivo.  FEBS Lett. 1999;  453 361-364
• 63 Kikuchi M, Tenneti L, Lipton S A. Role of p38 mitogen-activated protein kinase in axotomy-induced apoptosis of rat retinal ganglion cells.  J Neurosci. 2000;  20 5037-5044
• 64 Kline L B, Morawetz R B, Swaid S N. Indirect injury of the optic nerve.  Neurosurgery. 1984;  14 756-764
• 65 Koeberle P D, Ball A K. Nitric oxide synthase inhibition delays axonal degeneration and promotes the survival of axotomized retinal ganglion cells.  Exp Neurol. 1999;  158 366-381
• 66 Kostura M J, Tocci M J, Limjuco G. et al . Identification of a monocyte specific pre-interleukin 1βconvertase activity.  Proc Natl Acad Sci USA. 1989;  86 5227-5231
• 67 Kountakis S E, Maillard A A, El-Harazi S M. et al . Endoscopic optic nerve decompression for traumatic blindness.  Otolaryngol Head Neck Surg. 2000;  123 (1 Pt 1) 34-37
• 68 Kountakis S E, Maillard A A, Urso R. et al . Endoscopic approach to traumatic visual loss.  Otolaryngol Head Neck Surg. 1997;  116 (6 Pt 1) 652-655
• 69 Kozma R, Sarner S, Ahmed S. et al . Rho family GTPases and neuronal growth cone remodelling: relationship between increased complexity induced by Cdc42Hs, Rac1, and acetylcholine and collapse induced by RhoA and lysophosphatidic acid.  Mol Cell Biol. 1997;  17 1201-1211
• 70 Kreutzberg G W. Microglia: a sensor for pathological events in the CNS.  Trends Neurosci. 1996;  19 312-318
• 71 Kuhn T B, Brown M D, Wilcox C L. et al . Myelin and collapsin-1 induce motor neuron growth cone collapse through different pathways: inhibition of collapse by opposing mutants of rac1.  J Neurosci. 1999;  19 1965-1975
• 72 Lai R K, Chun T, Hasson D. et al . Alpha-2 adrenoceptor agonist protects retinal function after acute retinal ischemic injury in the rat.  Vis Neurosci. 2002;  19 175-185
• 73 Lehmann M, Fournier A, Selles-Navarro I. et al . Inactivation of Rho Signalling Pathway Promotes CNS Axon Regeneration.  J Neurosci. 1999;  19 7537-7547
• 74 Leon S, Yin Y, Nguyen J. et al . Lens injury stimulates axon regeneration in the mature rat optic nerve.  J Neurosci. 2000;  20 4615-4626
• 75 Levin L A, Beck R W, Joseph M P. et al . The treatment of traumatic optic neuropathy: the International Optic Nerve Trauma Study.  Ophthalmology. 1999;  106 1268-1277
• 76 Levine A J. p53, the cellular gatekeeper for growth and division.  Cell. 1997;  88 323-331
• 77 Li M, Shibata A, Li C. et al . Myelin-associated glycoprotein inhibits neurite/axon growth and causes growth cone collapse.  J Neurosci Res. 1996;  46 404-414
• 78 Litchfield W J, Wells W W. Inhibitory action of D-galactose on phagocyte metabolism and function.  Infect Immun. 1976;  13 728-734
• 79 Lubben B, Stoll W, Grenzebach U. Optic nerve decompression in the comatose and conscious patients after trauma.  Laryngoscope. 2001;  111 320-328
• 80 Lucius R, Gallinat S, Rosenstiel P. et al . The angiotensin II type 2 (AT2) receptor promotes axonal regeneration in the optic nerve of adult rats.  J Exp Med. 1998;  188 661-670
• 81 Lucius R, Sievers J. YVAD protect post-natal retinal ganglion cells against axotomy-induced but not free radical-induced axonal degeneration in vitro.  Brain Res Mol Brain Res. 1997;  48 181-184
• 82 Mackay D J, Nobes C D, Hall A. The Rho’s progress: a potential role during neuritogenesis for the Rho family of GTPases.  Trends Neurosci. 1995;  18 496-501
• 83 Mansour-Robaey S, Clarke D B, Wang Y C. et al . Effects of ocular injury and administration of brain-derived neurotrophic factor on survival and regrowth of axotomized retinal ganglion cells.  Proc Natl Acad Sci USA. 1994;  91 1632-1636
• 84 Maurer J, Hinni M, Mann W. et al . Optic nerve decompression in trauma and tumor patients.  Eur Arch Otorhinolaryngol. 1999;  256 341-345
• 85 McKerracher L, Vidal-Sanz M, Essagian C. et al . Selective impairment of slow axonal transport after optic nerve injury in adult rats.  J Neurosci. 1990;  10 2834-2841
• 86 Minghetti L, Nicolini A, Polazzi E. et al . Down-regulation of microglial cyclo-oxygenase-2 and inducible nitric oxide synthase expression by lipocortin 1.  Br J Pharmacol. 1999;  126 1307-1314
• 87 Moore S, Thanos S. The concept of microglia in relation to central nervous system disease and regeneration.  Progr Neurobiol. 1996;  48 441-460
• 88 Nacif-Coelho C, Correa-Sales C, Chang L L. et al . Perturbation of ion channel conductance alters the hypnotic response to the α2-adrenergic agonist dexmedetomidine in the locus coeruleus of the rat.  Anesthesiology. 1994;  81 1527-1534
• 89 Needham L K, Tennekoon G I, McKhann G M. Selective growth of rat Schwann cells in neuron- and serum-free primary culture.  J Neurosci. 1987;  7 1-9
• 90 Nickells R W. Apoptosis of retinal ganglion cells in glaucoma: An update of the molecular pathways involved in cell death.  Surv Ophthalmol. 1999;  43 (Suppl 1) 151-161
• 91 Nishiki T, Narumiya S, Morii N. et al . ADP-ribosylation of the rho/rac proteins induces growth inhibition, neurite outgrowth and acetylcholine esterase in cultured PC-12 cells.  Biochem Biophys Res Commun. 1990;  167 265-272
• 92 Osborne N N, Chidlow G, Wood J PM. et al . Expectations in the treatment of retinal diseases: Neuroprotection.  Curr Eye Res. 2001;  22 321-332
• 93 Oshitari T, Adachi-Usami E. The effect of caspase inhibitors and neurotrophic factors on damaged retinal ganglion cells.  Neuroreport. 2003;  14 289-292
• 94 Phillis J W, Estevez A Y, O’Regan M H. Protective effects of the free radical scavengers, dimethyl sulfoxide and ethanol, in cerebral ischemia in gerbils.  Neurosci Lett. 1998;  244 109-111
• 95 Pomeranz H D, Rizzo J F, Lessell S. Treatment of traumatic optic neuropathy.  Int Ophthalmol Clin. 1999;  39 185-194
• 96 Purves D, Nja A. Effect of nerve growth factor on synaptic depression after axotomy.  Nature. 1976;  260 35-536
• 97 Quigley H A, Nickells R W, Kerrigan L A. et al . Retinal ganglion cell death in experimental glaucoma and after axotomy occurs by apoptosis.  Invest. Ophthalmol Vis Sci. 1995;  36 774-786
• 98 Rajiniganth M G, Gupta A K, Gupta A. et al . Traumatic optic neuropathy: visual outcome following combined therapy protocol.  Arch Otolaryngol Head Neck Surg. 2003;  129 1203-1206
• 99 Reichert F, Saada A, Rotshenker S. Peripheral nerve injury induces Schwann cells to express two macrophage phenotypes: phagocytosis and the galactose-specific lectin MAC-2.  J Neurosci. 1994;  14 3231-3245
• 100 Rosenbaum D M, Rosenbaum P S, Gupta H. et al . The role of the p53 protein in the selective vulnerability of the inner retina to transient ischemia.  Invest Ophthalmol Vis Sci. 1998;  39 2132-2139
• 101 Rosenstiel P, Schramm P, Isenmann S. et al . Differential effects of immunophilin-ligands (FK506 and V-10,367) on survival and regeneration of rat retinal ganglion cells in vitro and after optic nerve crush in vivo.  J Neurotrauma. 2003;  20 297-307
• 102 Ruoslahti E, Pierschbacher M D. New perspectives in cell adhesion: RGD and integrins.  Science. 1987;  238 491-497
• 103 Russelakis-Carneiro M, Silveira L C, Perry V H. Factors affecting the survival of cat retinal ganglion cells after optic nerve injury.  J Neurocytol. 1996;  25 393-402
• 104 Saatman K E, Abai B, Grosvenor A. et al . Traumatic axonal injury results in biphasic calpain activation and retrograde transport impairment in mice.  J Cereb Blood Flow Metab. 2003;  23 34-42
• 105 Saleh A, Srinivasula S M, Acharya S. et al . Cytochrome c and dATP-mediated oligomerization of Apaf-1 is a prerequisite for procaspase-9 activation.  J Biol Chem. 1999;  274 17 941-17 945
• 106 Sasaki H, Coffey P, Villegas-Perez M P. et al . Light induced EEG desynchronization and behavioral arousal in rats with restored retinocollicular projection by peripheral nerve graft.  Neurosci Lett. 1996;  218 45-48
• 107 Sauvé Y, Sawai H, Rasminsky M. Functional synaptic connections made by regenerated retinal ganglion cell axons in the superior colliculus of adult hamsters.  J Neurosci. 1995;  15 665-675
• 108 Schütz E, Rose K, Thanos S. Regeneration of ganglion cell axons into a peripheral nerve graft alters retinal expression of glial markers and decreases vulnerability to re-axotomy.  Restor Neurol Neurosci. 2003;  21 11-18
• 109 Shimizu S, Simon R P, Graham S H. Dimethylsulfoxide (DMSO) treatment reduces infarction volume after permanent focal cerebral ischemia in rats.  Neurosci Lett. 1997;  239 125-127
• 110 Skene J H, Willard M. Changes in axonally transported proteins during axon regeneration in toad retinal ganglion cells.  J Cell Biol. 1981;  89 86-95
• 111 So K F, Yip H K. Regenerative capacity of retinal ganglion cells in mammals.  Vision Res. 1998;  38 1525-1535
• 112 Stewart M L, Grollman A P, Huang M T. Aurintricarboxylic acid: inhibitor of initiation of protein synthesis.  Proc Natl Acad Sci USA. 1971;  68 97-101
• 113 Thakar A, Mahapatra A K, Tandon D A. Delayed optic nerve decompression for indirect optic nerve injury.  Laryngoscope. 2003;  113 112-119
• 114 Thanos S. Adult retinofugal axons regenerating through peripheral nerve grafts can restore the light-induced pupilloconstriction reflex.  Eur J Neurosci. 1992;  4 691-699
• 115 Thanos S, Mey J. Type-specific stabilization and target-dependent survival of regenerating ganglion cells in the retina of adult rats.  J Neurosci. 1995;  15 1057-1079
• 116 Thanos S, Mey J, Wild M. Treatment of the adult retina with microglia-suppressing factors retards axotomy-induced neuronal degradation and enhances axonal regeneration in vivo and in vitro.  J Neurosci. 1993;  13 455-466
• 117 Thanos S, Moore S, Hong Y M. Retinal microglia.  Progr Ret Eye Res. 1996;  15 331-361
• 118 Thanos S, Naskar R, Heiduschka P. Regenerating ganglion cell axons in the adult rat establish retinofugal topography and restore visual function.  Exp Brain Res. 1997;  114 483-491
• 119 Thanos S, Naskar R, Mey J. et al . Timing of fiber arrival and dennervation of postsynaptic neurones is required for restoration of visual perception by regenerating axons.  J Brain Res. 1996;  37 255-267
• 120 Umihira J, Lindsey J D, Weinreb R N. Simultaneous expression of c-Jun and p53 in retinal ganglion cells of adult rat retinal slice cultures.  Curr Eye Res. 2002;  24 147-159
• 121 Van Leeuwen F N, Kain H E, van der Kammen R A. et al . The guanine nucleotide exchange factor Tiam1 affects neuronal morphology; opposing roles for the small GTPases Rac and Rho.  J Cell Biol. 1997;  139 797-807
• 122 Vanselow J, Schwab M E, Thanos S. Responses of regenerating rat retinal ganglion cell axons to contacts with central nervous myelin in vitro.  Eur J Neurosci. 1990;  2 121-125
• 123 Varon S, Adler R. Trophic and specifying factors directed to neuronal cells.  Adv Cell Neurobiol. 1981;  2 115-163
• 124 Vidal-Sanz M, Lafuente M P, Mayor-Torroglosa S. et al . Brimonidine’s neuroprotective effects against transient ischaemia-induced retinal ganglion cell death.  Eur J Ophthalmol. 2001;  11 (Suppl 2) 36-40
• 125 Vorwerk C K. Neuroprotektion retinaler Erkrankungen. Mythos oder Realität?.  Ophthalmologe. 2001;  98 106-123
• 126 Walters T R. Development and use of brimonidine in treating acute and chronic elevations of intraocular pressure: a review of safety, efficacy, dose response, and dosing studies.  Surv Ophthalmol. 1996;  41 (Suppl. 1) 19-26
• 127 Wang H G, Pathan N, Ethell I M. et al . Ca2 +-induced apoptosis through calcineurin dephosphorylation of BAD.  Science. 1999;  284 339-343
• 128 Weibel D, Cadelli D, Schwab M E. Regeneration of lesioned rat optic nerve fibers is improved after neutralization of myelin-associated neurite growth inhibitors.  Brain Res. 1994;  642 259-266
• 129 Wheeler L A, Gil D W, WoldeMussie E. Role of alpha-2 adrenergic receptors in neuroprotection and glaucoma.  Surv Ophthalmol. 2001;  45 (Suppl 3) 290-294
• 130 Wheeler L A, Lai R, Woldemussie E. From the lab to the clinic: activation of an alpha-2 agonist pathway is neuroprotective in models of retinal and optic nerve injury.  Eur. J. Ophthalmol. 1999;  9 (Suppl 1) 17-21
• 131 Weishaupt J H, Diem R, Kermer P. et al . Contribution of caspase-8 to apoptosis of axotomized rat retinal ganglion cells in vivo.  Neurobiol Dis. 2003;  13 124-135
• 132 Wictorin K, Brundin P, Gustavii B. et al . Reformation of long axon pathways in adult rat central nervous system by human forebrain neuroblasts.  Nature. 1990;  347 556-558
• 133 Wictorin K, Brundin P, Sauer H. et al . Long distance directed axonal growth from human dopaminergic mesencephalic neuroblasts implanted along the nigrostriatal pathway in 6-hydroxydopamine lesioned adult rats.  J Comp Neurol. 1992;  323 475-494
• 134 Williams J A. Disintegrins: RGD-containing proteins which inhibit cell/matrix interactions (adhesion) and cell/cell interactions (aggregation) via the integrin receptors.  Pathol Biol. 1992;  40 813-821
• 135 Witting A, Muller P, Herrmann A. et al . Phagocytic clearance of apoptotic neurons by microglia/brain macrophages in vitro: involvement of lectin-, integrin-, and phosphatidylserine-mediated recognition.  J Neurochem. 2000;  75 1060-1070
• 136 Wohlrab T M, Maas S, de Carpentier J P. Surgical decompression in traumatic optic neuropathy.  Acta Ophthalmol. Scand. 2002;  80 287-293
• 137 WoldeMussie E, Ruiz G, Wijono M. et al . Neuroprotection of retinal ganglion cells by brimonidine in rats with laser-induced chronic ocular hypertension.  Invest Ophthalmol Vis Sci. 2001;  42 2849-2855
• 138 Yin Y, Cui Q, Li Y. et al . Macrophage-derived factors stimulate optic nerve regeneration.  J Neurosci. 2003;  23 2284-2293
• 139 Yip H K, So K F. Axonal regeneration of retinal ganglion cells: effect of trophic factors.  Progr Ret Eye Res. 2000;  19 559-575
• 140 Yoles E, Wheeler L A, Schwartz M. Alpha2-adrenoreceptor agonists are neuroprotective in a rat model of optic nerve degeneration.  Invest Ophthalmol Vis Sci. 1999;  40 65-73
• 141 Yoshida K, Behrens A, Le-Niculescu H. et al . Amino-terminal phosphorylation of c-Jun regulates apoptosis in the retinal ganglion cells by optic nerve transection.  Invest Ophthalmol Vis Sci. 2002;  43 1631-1635
• 142 Zeng B Y, Anderson P N, Campbell G. et al . Regenerative and other responses to injury in the retinal stump of the optic nerve in adult albino rats: transection of the intracranial optic nerve.  J Anat. 1995;  186 495-508
• 143 Zhivotovsky B, Wade D, Nicotera P. et al . Role of nucleases in apoptosis.  Int. Arch Allergy Immunol. 1994;  105 333-338