title: P2 receptor antagonists prevent synaptic failure and extracellular signal-regulated kinase 1/2 activation induced by oxygen and glucose deprivation in rat CA1 hippocampus in vitro.
abstract: To investigate the role of purinergic P2 receptors under ischemia, we studied the effect of P2 receptor antagonists on synaptic transmission and mitogen-activated protein kinase (MAPK) activation under oxygen and glucose deprivation (OGD) in rat hippocampal slices. The effect of the P2 antagonists pyridoxalphosphate-6-azophenyl-2',4'-disulfonate (PPADS, unselective, 30 μm), N( 6) -methyl-2'-deoxyadenosine-3',5'-bisphosphate (MRS2179, selective for P2Y(1) receptor, 10 μm), Brilliant Blue G (BBG, selective for P2X(7) receptor, 1 μm), and 5-[[[(3-phenoxyphenyl)methyl][(1S)-1,2,3,4-tetrahydro-1-naphthalenyl]amino]carbonyl]-1,2,4-benzenetricarboxylic acid (A-317491, selective for P2X(3) receptor, 10 μm), and of the newly synthesized P2X(3) receptor antagonists 2-amino-9-(5-iodo-2-isopropyl-4-methoxybenzyl)adenine (PX21, 1 μm) and 2-amino-9-(5-iodo-2-isopropyl-4-methoxybenzyl)-N( 6)-methyladenine (PX24, 1 μm), on the depression of field excitatory postsynaptic potentials (fEPSPs) and anoxic depolarization (AD) elicited by 7 min of OGD were evaluated. All antagonists significantly prevented these effects. The extent of CA1 cell injury was assessed 3 h after the end of 7 min of OGD by propidium iodide staining. Substantial CA1 pyramidal neuronal damage, detected in untreated slices exposed to OGD injury, was significantly prevented by PPADS (30 μm), MRS2179 (10 μm), and BBG (1 μm). Western blot analysis showed that, 10 min after the end of the 7 min of OGD, extracellular signal-regulated kinase (ERK)1/2 MAPK activation was significantly increased. MRS2179, BBG, PPADS and A-317491 significantly counteracted ERK1/2 activation. Hippocampal slices incubated with the ERK1/2 inhibitors 1,4-diamino-2,3-dicyano-1,4-bis(2-aminophenylthio)butadiene (U0126, 10 μm) and α-[amino[(4-aminophenyl)thio]methylene]-2-(trifluoromethyl) benzeneacetonitrile (SL327, 10 μm) showed significant fEPSP recovery after OGD and delayed AD, supporting the involvement of ERK1/2 in neuronal damage induced by OGD. These results indicate that subtypes of hippocampal P2 purinergic receptors have a harmful effect on neurotransmission in the CA1 hippocampus by participating in AD appearance and activation of ERK1/2.
authors: Department of Preclinical and Clinical Pharmacology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy.
authors: Chiara
authors: C
authors: Traini
authors: Felicita
authors: F
authors: Pedata
authors: Sara
authors: S
authors: Cipriani
authors: Tommaso
authors: T
authors: Mello
authors: Andrea
authors: A
authors: Galli
authors: Maria Grazia
authors: MG
authors: Giovannini
authors: Francesca
authors: F
authors: Cerbai
authors: Rosaria
authors: R
authors: Volpini
authors: Gloria
authors: G
authors: Cristalli
authors: Anna Maria
authors: AM
authors: Pugliese
mesh_terms: D000818:Animals; D056547:CA1 Region, Hippocampal / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D015687:Cell Hypoxia / Q000187:drug effects; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D007003:Hypoglycemia / Q000188:drug therapy / Q000503:physiopathology; D066298:In Vitro Techniques; D007511:Ischemia / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D009410:Nerve Degeneration / Q000188:drug therapy / Q000503:physiopathology; D058919:Purinergic P2 Receptor Antagonists / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D009435:Synaptic Transmission / Q000187:drug effects*
chemical_list: D058919:Purinergic P2 Receptor Antagonists; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3