1998 Fiscal Year Final Research Report Summary
Neurophysiological study for excitatory amino acids-induced neurotoxicity and apoptosis in cultured retinal neurons.
| Project/Area Number |
09671801
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Ophthalmology
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| Research Institution | HIROSHIMA UNIVERSITY |
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Principal Investigator |
MISHIMA Hiromu Faculty of Medicine, Professor, 医学部, 教授 (20034100)
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| Co-Investigator(Kenkyū-buntansha) |
MINAMOTO Atushi Facalty of Medicine, Assistant Professor, 医学部, 講師 (10253072)
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| Project Period (FY) |
1997 – 1998
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| Keywords | glutamate / VIP / PACAP / retinal ganglion cell / magnetic cell sorter |
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| Research Abstract |
1. Protection of vasoactive intestinal peptide (VIP) against glutamate-induced neurotoxicity in cultured retinal neurons.
VIP (10 nM - 1 muM) was attenuated glutamate-induced neurotoxicity in a concentration-dependent manner. This protective effect was antagonized by VIP6-28, a VIP recptor antagonist, and H-89, a protein kinase A (PKA) inhibitor. VIP did not affect glutamate-induced current and Ca^<2+> influx. VIP is suggested to act as a protective factor against glutamate-induced neurotoxicity of retinal neurons by elevating the cAMP level via VIP receptors. Activated PKA might have an effect downstream of the Ca^<2+> influx in glutamate neurotoxicity.
2. Protection of pituitary adenylate cyclase activating peptide (PACAP) against glutamate-induced neurotoxicity in cultured retinal neurons.
PACAP27 (10 nM - 1 muM) and PACAP38 (10 nM - 1 muM) were attenuated glutamate-induced neurotoxicity in a concentration-dependent manner. Activation of mitogen activated protein (MAP) kinase by PACAPs was inhibited by H-89. PACAPs are suggested to act as neuroprotective factors against glutamate-induced neurotoxicity by activating MAP kinase, which is due to PKA activation via PACAP receptors.
3. Rat retinal ganglion cells (RGCs) culture enriched with the magnetic cell sorter (MACS).
We demonstrated a new RGC-culture technique using MACS.It enriched RGCs from 0.55 % to 31.0 % of all retinal neurons and enhanced the survival of enriched RGCs for over 2 weeks. The whole-cell patch clamp evaluation was suggested that three ionotropic glutamate receptor subtypes such as NMDA, kainate and AMIPA receptors existed on MACS-separated RGCs. This culture system is thought to be an appropriate model for studying glutamate-induced neurotoxicity in RGC.
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