title: Nitric oxide enhances amino acid release from immature chick embryo retina.
abstract: Nitric oxide (NO) was investigated for its ability to induce amino acid release from immature chick retina. The production of endogenous NO by activation of NO synthase after stimulation of N-methyl-D-aspartate (NMDA) subtype of glutamate receptor caused a significant increase in basal release of gamma-aminobutyric acid (GABA) and glutamine, whereas a more modest increase in the glutamate release was also observed. The exposure of chick retina from 9-day-old embryos to NO-generating compounds, S-nitroso-N-acetylpe-nicillamine (SNAP) and sodium nitroprusside (SNP) produced a dose dependent increase in GABA, glutamine, and glutamate release. This effect was reduced by about 80% by haemoglobin. These results indicate that NO has a stimulatory effect on amino acid release from chick embryo immature retina. However, this effect does not appear to involve a cGMP-related mechanism because 8-bromo-cGMP, a stable analogue of cGMP, failed to affect spontaneous amino acid release and because zaprinast did not enhance NMDA-stimulated release. In conclusion, our present observations may account for a role of NMDA-mediated events in the biochemical maturation under depolarizing conditions.
authors.affiliation: Institute of Biochemical Sciences and Clinical Biochemistry, University of Messina, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Ientile
authors.forename: V
authors.initials: V
authors.lastname: Picciurro
authors.forename: S
authors.initials: S
authors.lastname: Pedale
authors.forename: C
authors.initials: C
authors.lastname: Nucci
authors.forename: B
authors.initials: B
authors.lastname: Malecka
authors.forename: G
authors.initials: G
authors.lastname: Nisticò
authors.forename: S
authors.initials: S
authors.lastname: Macaione
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D005314:Embryonic and Fetal Development; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D006454:Hemoglobins / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology; D010396:Penicillamine / Q000031:analogs & derivatives / Q000494:pharmacology; D017470:Receptors, Glutamate / Q000502:physiology; D012160:Retina / Q000196:embryology* / Q000378:metabolism*; D026423:S-Nitroso-N-Acetylpenicillamine; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D000596:Amino Acids; D004791:Enzyme Inhibitors; D006454:Hemoglobins; D017470:Receptors, Glutamate; D005973:Glutamine; D009599:Nitroprusside; D009569:Nitric Oxide; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D026423:S-Nitroso-N-Acetylpenicillamine; D010396:Penicillamine