[Molecular biological aspects of neuroplasticity: approaches for treating tinnitus and hearing disorders].
Peripheral and central structures are involved in the onset of tinnitus. Neuronal plasticity is of special importance for the occurrence of central tinnitus and its persistent form. Neuronal plasticity is the ability of the brain to adapt its own structure (synapses, nerve cells, or even whole areas of the brain) and its organization to modified biological requirements. Neuroplasticity is an ongoing dynamic process. Generally speaking, there are two types of plasticity: synaptic and cortical. Cortical plasticity involves activity-dependent changes in size, connectivity, or in the activation pattern of cortical networks. Synaptic plasticity refers to the activity-dependent change in the strength of synaptic transmission and can affect both the morphology and physiology of the synapse. The stimulation of afferent fibers leads to long-lasting changes in synaptic transmission. This phenomenon is called long-term potentiation (LTP) or long-term depression (LTD). From the perspective of molecular biology, synaptic plasticity is of particular importance for the development of tinnitus and its persistence. Ultimately, the damage to the hair cells, auditory nerve, and excitotoxicity results in an imbalance between LTP and LTD and thus in changes of synaptic plasticity. After excessive acoustic stimulation, LTP can be induced by the increase of afferent inputs, whereas decreased afferent inputs generate LTD. The imbalance between LTP and LTD leads to changes in gene expression and involves changes in neurotransmission, in the expression of the receptors, ion channels, regulatory enzymes, and in direct changes on the synapses. This causes an increase of activity on the cellular level. As a result, the imbalance can lead to hyperactivity in the dorsal cochlear nucleus, inferior colliculus, and in the auditory cortex and, later on, to changes in cortical plasticity leading to tinnitus.
Mazurek
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HNO-Klinik und Poliklinik, Tinnituszentrum und molekularbiologisches Forschungslabor, Charité - Universitätsmedizin Berlin, Campus Charité Mitte, Charitéplatz 1, 10117 Berlin. birgit.mazurek@charite.de
Olze
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Haupt
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H
Klapp
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BF
Adli
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Gross
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Szczepek
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AJ
D000818:Animals; D001921:Brain / Q000503:physiopathology*; D006801:Humans; D008959:Models, Neurological; D009415:Nerve Net / Q000503:physiopathology*; D009473:Neuronal Plasticity; D009435:Synaptic Transmission; D014012:Tinnitus / Q000503:physiopathology* / Q000628:therapy*
Proc Natl Acad Sci U S A. 2007 Feb 27;104(9):3550-5
17360680
J Neurosci. 2006 May 31;26(22):5888-93
16738230
Hear Res. 2000 Sep;147(1-2):145-59
10962181
J Neurosci. 2006 Apr 12;26(15):3933-41
16611809
Psychoneuroendocrinology. 2009 Dec;34 Suppl 1:S208-16
19541429
Neurobiol Aging. 1999 Nov-Dec;20(6):643-53
10674430
Trends Neurosci. 2004 Nov;27(11):676-82
15474168
Learn Mem. 2003 Mar-Apr;10(2):86-98
12663747
Nat Rev Neurosci. 2000 Oct;1(1):67-73
11252770
Exp Brain Res. 2003 Dec;153(4):649-54
14508632
Brain Res Dev Brain Res. 2002 Dec 15;139(2):139-50
12480128
Nervenarzt. 2006 May;77(5):523-37
16078056
J Neurosci Res. 2002 Oct 1;70(1):1-7
12237859
Ann N Y Acad Sci. 1999 Nov 28;884:249-54
10842598
Neurotoxicol Teratol. 2000 Mar-Apr;22(2):175-81
10758346
Brain. 2006 Jul;129(Pt 7):1659-73
16672292
Neuroreport. 1999 Jun 23;10(9):1879-82
10501525
Nervenarzt. 2008 Sep;79(9):1006-16
18661117
Eur J Neurosci. 2002 Dec;16(12):2394-404
12492434
J Neurosci. 2000 Mar 1;20(5):1912-21
10684892
Proc Natl Acad Sci U S A. 2003 Jan 7;100(1):265-70
12486245
Psychiatr Prax. 2004 Nov;31 Suppl 2:S215-23
15586313
Otol Neurotol. 2007 Feb;28(2):178-84
17255884
Prog Brain Res. 2008;169:145-58
18394472
Biol Psychiatry. 2003 Jul 1;54(1):70-5
12842310
Otolaryngol Clin North Am. 2003 Apr;36(2):249-66, v-vi
12856295
Mol Pharmacol. 2008 Sep;74(3):595-604
18524887
Mol Psychiatry. 2002;7 Suppl 1:S46-56
11986995
Neuroscientist. 2007 Oct;13(5):492-505
17901258
J Neuropsychiatry Clin Neurosci. 2001 Spring;13(2):290-300; dscussion 289
11449037
Med Hypotheses. 2003 Oct;61(4):446-8
13679010
J Commun Disord. 2007 Jul-Aug;40(4):313-34
17418230
Hear Res. 2000 Sep;147(1-2):251-60
10962189
HNO. 2007 Dec;55(12):964-71
17943261
J Neurosci. 1997 Nov 15;17(22):8695-701
9348338
Neuropsychopharmacology. 2008 Jan;33(1):18-41
17728696
Nervenarzt. 2002 Jul;73(7):595-9
12212521
Psychiatry Res. 2002 Mar 15;109(2):143-8
11927139
J Neurosci. 2005 Apr 13;25(15):3908-18
15829643
Dtsch Med Wochenschr. 2009 Jul;134 Suppl 4:S127-31
19554493
Synapse. 2002 Dec 1;46(3):170-88
12325044
Prog Neurobiol. 2005 Jun;76(2):99-125
16099088
Neurobiol Aging. 2007 Apr;28(4):586-601
16580094
Development. 2003 Jan;130(2):391-9
12466205
Brain Res Mol Brain Res. 1996 Mar;36(2):280-6
8965648
Eur J Neurosci. 2004 Sep;20(5):1348-54
15341606
Eur J Neurosci. 2000 Jan;12(1):345-52
10651889
Neuropharmacology. 1998 Dec;37(12):1553-61
9886678
Prog Brain Res. 2007;166:89-106
17956775
Rev Neurol. 1998 Apr;26(152):554-60
9796004
Nat Rev Neurosci. 2001 Jan;2(1):24-32
11253356
Exp Gerontol. 1995 May-Aug;30(3-4):349-60
7556513
Hear Res. 1990 Dec;50(1-2):245-57
2076976
Sci STKE. 2004 Mar 16;2004(225):re5
15039492
J Neurosci. 1998 Apr 15;18(8):2974-81
9526014
J Neurosci. 2003 Nov 12;23(32):10359-67
14614095
Physiol Rev. 2005 Apr;85(2):523-69
15788705
Nat Med. 1998 Nov;4(11):1313-7
9809557
J Physiol. 1973 Jul;232(2):331-56
4727084
Annu Rev Neurosci. 2008;31:563-90
18558867
Hear Res. 2004 Sep;195(1-2):17-34
15350276
Hear Res. 2005 Aug;206(1-2):200-26
16081009
Drug Discov Today. 2005 Oct 1;10(19):1283-90
16214672
Neuroscience. 2009 Apr 21;160(1):227-39
19217931
Neuroscience. 1999;93(4):1375-81
10501462
Nat Rev Neurosci. 2007 Nov;8(11):844-58
17948030
Hear Res. 2006 Feb;212(1-2):9-21
16307852
Hear Res. 1999 Sep;135(1-2):146-62
10491963
Neuroscience. 2007 Mar 16;145(2):715-26
17275194
Nervenarzt. 2007 Nov;78 Suppl 3:531-47; quiz 548-9
17960353
Hear Res. 2000 Sep;147(1-2):261-74
10962190
Hear Res. 1996 Aug;97(1-2):46-53
8844185
J Am Acad Audiol. 2000 Mar;11(3):162-77
10755812
Prog Neurobiol. 2000 Dec;62(6):583-631
10880852
Cell. 2003 Jan 24;112(2):257-69
12553913
Neuroscience. 2009 Mar 3;159(1):325-34
19154777
Ageing Res Rev. 2004 Nov;3(4):431-43
15541710
Brain Res. 2009 Aug 4;1283:25-33
19520065