Premium
Cellular Mechanisms of Protection by Metabotropic Glutamate Receptors During Anoxia and Nitric Oxide Toxicity
Author(s) -
Maiese Kenneth,
Swiriduk Margaret,
TenBroeke Michelle
Publication year - 1996
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1046/j.1471-4159.1996.66062419.x
Subject(s) - metabotropic glutamate receptor , metabotropic glutamate receptor 5 , metabotropic glutamate receptor 2 , glutamate receptor , metabotropic glutamate receptor 6 , nitric oxide , metabotropic receptor , toxicity , metabotropic glutamate receptor 7 , chemistry , metabotropic glutamate receptor 4 , pharmacology , metabotropic glutamate receptor 1 , metabotropic glutamate receptor 8 , neuroscience , receptor , biology , biochemistry , organic chemistry
Metabotropic glutamate receptors, nitric oxide (NO), and the signal transduction pathways of protein kinase C (PKC) and protein kinase A (PKA) can independently alter ischemic‐induced neuronal cell death. We therefore examined whether the protective effects of metabotropic glutamate receptors during anoxia and NO toxicity were mediated through the cellular pathways of PKC or PKA in primary hippocampal neurons. Pretreatment with the metabotropic glutamate receptor agonists (±)‐1‐aminocyclopentane‐ trans ‐1,3‐dicarboxylic acid, (1 S ,3 R )‐1‐aminocyclopentane‐1,3‐dicarboxylic acid (1 S ,3 R ‐ACPD), and l (+)‐2‐amino‐4‐phosphonobutyric acid ( l ‐AP4) 1 h before anoxia or NO exposure increased hippocampal neuronal cell survival from ∼30 to 70%. In addition, posttreatment with 1 S ,3 R ‐ACPD or l ‐AP4 up to 6 h following an insult attenuated anoxic‐ or NO‐induced neurodegeneration. In contrast, treatment with l ‐(+)‐2‐amino‐3‐phosphonopropionic acid, an antagonist of the metabotropic glutamate receptor, did not significantly alter neuronal survival during anoxia or NO exposure. Protection by the ACPD‐sensitive metabotropic receptors, such as the subtypes mGluR1α, mGluR2, and mGluR5, appears to be dependent on the modulation of PKC activity. In contrast, l ‐AP4‐sensitive metabotropic glutamate receptors, such as the subtype mGluR4, may increase neuronal survival through PKA rather than PKC. Thus, activation of specific metabotropic glutamate receptors is protective during anoxia and NO toxicity, but the signal transduction pathways mediating protection differ among the metabotropic glutamate receptor subtypes.