Role of nitric oxide in a fast retrograde signal during development.
Two retrograde signals influence the chick embryo's isthmo-optic nucleus, which projects to the retina: a slow-acting survival signal due to uptake of neurotrophic factors, and a fast-acting death signal initiated by calcium entry into isthmo-optic terminals due to electrical activity. The latter signal also affects dendritic reorganization. Since nitric oxide synthase is present in isthmo-optic terminals and their retinal target cells, we have tested its possible role in the fast-acting signal. Intraocular injection of nitric oxide antagonists led within 6-12 h to a reduction in the number of dying isthmo-optic neurons and slowed dendritic reorganization. Surprisingly, nitric oxide agonists had a similar fast effect on neuronal death. Although the mechanism appears to be complex, nitric oxide is involved in mediating the fast-acting retrograde signal.
Posada
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A
Institut de Biologie Cellulaire et de Morphologie, Université de Lausanne, Rue du Bugnon 9, CH-1005, Lausanne, Switzerland.
Clarke
P G
PG
D000818:Animals; D001120:Arginine / Q000494:pharmacology; D001565:Benzoates / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002642:Chick Embryo; D003712:Dendrites / Q000737:chemistry / Q000502:physiology*; D007093:Imidazoles / Q000494:pharmacology; D009414:Nerve Growth Factors / Q000494:pharmacology; D009474:Neurons / Q000737:chemistry / Q000201:enzymology* / Q000648:ultrastructure; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D009603:Nitroso Compounds / Q000494:pharmacology; D009900:Optic Nerve / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D017729:Presynaptic Terminals / Q000737:chemistry / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
D001565:Benzoates; D007093:Imidazoles; D009414:Nerve Growth Factors; D009603:Nitroso Compounds; C079393:1,3-dihydroxy-4,4,5,5-tetramethyl-2-(4-carboxyphenyl)tetrahydroimidazole; C094210:2,2'-(hydroxynitrosohydrazono)bis-ethanamine; D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase