Abstract
Trophic factor deprivation induces neuronal nitric oxide synthase (NOS) and apoptosis of rat embryonic motor neurons in culture. We report here that motor neurons constitutively express endothelial NOS that helps support the survival of motor neurons cultured with brain-derived neurotrophic factor (BDNF) by activating the nitric oxide-dependent soluble guanylate cyclase. Exposure of BDNF-treated motor neurons to nitro-L-arginine methyl ester (L-NAME) decreased cell survival 40-50% 24 hr after plating. Both low steady-state concentrations of exogenous nitric oxide (<0.1 microM) and cGMP analogs protected BDNF-treated motor neurons from death induced by L-NAME. Equivalent concentrations of cAMP analogs did not affect cell survival. Inhibition of nitric oxide-sensitive guanylate cyclase with 2 microM 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) reduced the survival of BDNF-treated motor neurons by 35%. cGMP analogs also protected from ODQ-induced motor neuron death, whereas exogenous nitric oxide did not. In all cases, cell death was prevented with caspase inhibitors. Our results suggest that nitric oxide-stimulated cGMP synthesis helps to prevent apoptosis in BDNF-treated motor neurons.
Publication types
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Research Support, U.S. Gov't, P.H.S.
MeSH terms
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8-Bromo Cyclic Adenosine Monophosphate / pharmacology
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Amino Acid Chloromethyl Ketones / pharmacology
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Animals
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Apoptosis / drug effects
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Apoptosis / physiology
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Brain-Derived Neurotrophic Factor / pharmacology*
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Cell Survival / drug effects
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Cell Survival / physiology
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Cells, Cultured
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Cyclic GMP / metabolism*
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Cysteine Proteinase Inhibitors / pharmacology
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Enzyme Inhibitors / pharmacology
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Fetus / cytology
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Guanylate Cyclase / antagonists & inhibitors
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Guanylate Cyclase / metabolism
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Motor Neurons / cytology*
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Motor Neurons / drug effects
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Motor Neurons / enzymology
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NG-Nitroarginine Methyl Ester / pharmacology
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Nitric Oxide / metabolism*
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Nitric Oxide Synthase / metabolism
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Oligopeptides / pharmacology
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Oxadiazoles / pharmacology
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Quinoxalines / pharmacology
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Rats
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Solubility
Substances
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1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one
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Amino Acid Chloromethyl Ketones
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Brain-Derived Neurotrophic Factor
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Cysteine Proteinase Inhibitors
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Enzyme Inhibitors
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Oligopeptides
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Oxadiazoles
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Quinoxalines
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acetyl-aspartyl-glutamyl-valyl-aspartal
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benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone
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L 709049
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8-Bromo Cyclic Adenosine Monophosphate
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Nitric Oxide
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Nitric Oxide Synthase
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Guanylate Cyclase
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Cyclic GMP
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NG-Nitroarginine Methyl Ester