title: Reciprocal regulation between taurine and glutamate response via Ca2+-dependent pathways in retinal third-order neurons.
abstract: Although taurine and glutamate are the most abundant amino acids conducting neural signals in the central nervous system, the communication between these two neurotransmitters is largely unknown. This study explores the interaction of taurine and glutamate in the retinal third-order neurons. Using specific antibodies, both taurine and taurine transporters were localized in photoreceptors and Off-bipolar cells, glutamatergic neurons in retinas. It is possible that Off-bipolar cells release juxtaposed glutamate and taurine to activate the third-order neurons in retina. The interaction of taurine and glutamate was studied in acutely dissociated third-order neurons in whole-cell patch-clamp recording and Ca2+ imaging. We find that taurine effectively reduces glutamate-induced Ca2+ influx via ionotropic glutamate receptors and voltage-dependent Ca2+ channels in the neurons, and the effect of taurine was selectively inhibited by strychnine and picrotoxin, but not GABA receptor antagonists, although GABA receptors are present in the neurons. A CaMKII inhibitor partially reversed the effect of taurine, suggesting that a Ca2+/calmodulin-dependent pathway is involved in taurine regulation. On the other hand, a rapid influx of Ca2+ through ionotropic glutamate receptors could inhibit the amplitude and kinetics of taurine-elicited currents in the third-order neurons, which could be controlled with intracellular application of BAPTA a fast Ca2+ chelator. This study indicates that taurine is a potential neuromodulator in glutamate transmission. The reciprocal inhibition between taurine and glutamate in the postsynaptic neurons contributes to computation of visual signals in the retinal neurons.
authors.affiliation: College of Biomedical Science, Florida Atlantic University, Boca Raton, FL 33431, USA. sbulley@fau.edu
authors.forename: Simon
authors.initials: S
authors.lastname: Bulley
authors.forename: Wen
authors.initials: W
authors.lastname: Shen
mesh_terms: D025042:Amacrine Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D000557:Ambystoma; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000378:metabolism; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018756:GABA Antagonists / Q000494:pharmacology; D018698:Glutamic Acid / Q000378:metabolism*; D018684:Glycine Agents / Q000494:pharmacology; D007608:Kainic Acid / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D026901:Membrane Transport Proteins / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D010852:Picrotoxin / Q000494:pharmacology; D017470:Receptors, Glutamate / Q000378:metabolism; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D013331:Strychnine / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D013654:Taurine / Q000378:metabolism / Q000494:pharmacology*; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology; D000099247:Taurine Transporters
chemical_list: D002118:Calcium; D015220:Calcium Channels; D004791:Enzyme Inhibitors; D018690:Excitatory Amino Acid Agonists; D018756:GABA Antagonists; D018698:Glutamic Acid; D018684:Glycine Agents; D007608:Kainic Acid; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D018377:Neurotransmitter Agents; D010852:Picrotoxin; D017470:Receptors, Glutamate; D013331:Strychnine; D013654:Taurine; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D000099247:Taurine Transporters
references.citation: Brain Res. 1980 Sep 15;197(1):123-38
references.pmid: 6249454
references.citation: Brain Res. 2002 Jan 18;925(1):1-8
references.pmid: 11755895
references.citation: Brain Res. 2000 May 12;864(2):298-307
references.pmid: 10802037
references.citation: Brain Res. 2004 Sep 24;1021(2):232-40
references.pmid: 15342271
references.citation: Adv Exp Med Biol. 2009;643:169-79
references.pmid: 19239147
references.citation: FEBS Lett. 2004 Jul 2;569(1-3):123-8
references.pmid: 15225620
references.citation: Adv Exp Med Biol. 2006;583:299-306
references.pmid: 17153614
references.citation: Pflugers Arch. 1980 May;385(1):51-64
references.pmid: 6968058
references.citation: Brain Res. 1981 Feb 16;206(2):371-86
references.pmid: 7214140
references.citation: Mol Cell Neurosci. 2010 Apr;43(4):414-21
references.pmid: 20132888
references.citation: J Neurochem. 1976 Mar;26(3):609-11
references.pmid: 816997
references.citation: J Neurosci. 2008 Jan 2;28(1):106-15
references.pmid: 18171928
references.citation: Neuron. 2004 Mar 25;41(6):867-79
references.pmid: 15046720
references.citation: Neuron. 2004 Mar 25;41(6):839-41
references.pmid: 15046714
references.citation: J Neurosci Res. 1979;4(1):59-64
references.pmid: 423315
references.citation: Neuroscience. 2006;138(1):17-24
references.pmid: 16359816
references.citation: Vision Res. 2005 Mar;45(6):697-705
references.pmid: 15639496
references.citation: Adv Exp Med Biol. 2009;643:233-42
references.pmid: 19239154
references.citation: J Comp Neurol. 1996 Dec 16;376(3):343-60
references.pmid: 8956104
references.citation: Exp Eye Res. 1978 Dec;27(6):713 8
references.pmid: 104877
references.citation: J Neurosci Res. 1986;15(3):383-91
references.pmid: 3009837
references.citation: J Neurophysiol. 1994 Jul;72(1):471-4
references.pmid: 7965030
references.citation: J Nutr. 1988 Oct;118(10):1169-76
references.pmid: 3054019
references.citation: Prog Clin Biol Res. 1990;351:147-56
references.pmid: 2173000
references.citation: Brain Res. 2001 Mar 2;893(1-2):292-300
references.pmid: 11223021
references.citation: Neurochem Res. 1984 Apr;9(4):535-44
references.pmid: 6087177
references.citation: J Physiol. 2007 Jun 15;581(Pt 3):1001-18
references.pmid: 17395622
references.citation: J Neurophysiol. 2002 Mar;87(3):1629-34
references.pmid: 11877532
references.citation: J Neurophysiol. 2001 Apr;85(4):1384-94
references.pmid: 11287463
references.citation: Glia. 2002 Feb;37(2):153-68
references.pmid: 11754213
references.citation: Amino Acids. 2003;24(1-2):155-61
references.pmid: 12624748
references.citation: J Neurochem. 1989 Oct;53(4):1309-15
references.pmid: 2769270
references.citation: Amino Acids. 2008 Feb;34(2):321-8
references.pmid: 16955229
references.citation: Vis Neurosci. 1994 Nov-Dec;11(6):1115-34
references.pmid: 7841121
references.citation: Amino Acids. 2002;23(4):345-57
references.pmid: 12436202
references.citation: J Neurosci. 1995 Jul;15(7 Pt 2):5106-29
references.pmid: 7623139
references.citation: Amino Acids. 1999;17(4):323-34
references.pmid: 10707762
references.citation: Jpn J Pharmacol. 1983 Dec;33(6):1247-54
references.pmid: 6142135
references.citation: Brain Res. 2000 Mar 24;859(2):341-51
references.pmid: 10719083
references.citation: J Comp Neurol. 1997 Apr 21;380(4):449-71
references.pmid: 9087525
references.citation: Proc Natl Acad Sci U S A. 1996 Nov 12;93(23):13351-6
references.pmid: 8917594
references.citation: Amino Acids. 2000;19(3-4):593-604
references.pmid: 11140362
references.citation: Neurochem Res. 2005 Dec;30(12):1615-21
references.pmid: 16362781
references.citation: Anal Chem. 2004 Sep 1;76(17):5069-74
references.pmid: 15373444
references.citation: Vis Neurosci. 1999 Sep-Oct;16(5):835-42
references.pmid: 10580719
references.citation: J Neurochem. 1976 Jul;27(1):131-7
references.pmid: 1085346
references.citation: Nutr Neurosci. 2002 Apr;5(2):75-90
references.pmid: 12000086
references.citation: Neuropharmacology. 1990 Mar;29(3):243-7
references.pmid: 2158001
references.citation: J Neurosci. 1996 Nov 1;16(21):6807-29
references.pmid: 8824321
references.citation: Adv Exp Med Biol. 1998;442:463-76
references.pmid: 9635063
references.citation: Clin Exp Pharmacol Physiol. 2004 Apr;31(4):237-43
references.pmid: 15053820
references.citation: J Physiol. 1999 Feb 1;514 ( Pt 3):701-11
references.pmid: 9882741
references.citation: Neurochem Res. 2004 Jan;29(1):189-97
references.pmid: 14992278
references.citation: Eur J Neurosci. 2000 May;12(5):1647-53
references.pmid: 10792442
references.citation: J Physiol. 1997 Aug 1;502 ( Pt 3):609-21
references.pmid: 9279812
references.citation: Brain Res. 1980 Sep 15;197(1):139-51
references.pmid: 6249455