Evidence for the involvement of nitric oxide in the inhibitory effect of GSPYFVamide on Helix aspersa central neurones.
Intracellular recordings were made from neurones E-8, E-16 and E-13a in the visceral ganglion of Helix aspersa. GSPYFVamide inhibits the activity of these neurones and the role of a second messenger system in this inhibition was investigated. 8-Bromo-cGMP, 100 microM was found to potentiate this inhibition while ODQ, 100 microM, an inhibitor of guanylyl cyclase, almost completely blocked GSPYFVamide-induced inhibition. Four NO donors sodium nitroprusside, 100 microM, sodium nitrite, 1 mM, SNOG, 50 microM, and SNAP, 10-50 microM, all potentiated the GSPYFVamide-induced inhibition. L-NAME, 100-1000 microM, a competitive inhibitor of NOS, blocked the GSPYFVamide-induced inhibition. In some cases recovery was only partial. The possible role of NO in modulating the inhibitory response to GSPYFVamide is discussed.
Pedder
S M
SM
Department of Physiology and Pharmacology, School of Biological Sciences, Bassett Crescent East, University of Southampton, UK.
Muneoka
Y
Y
Walker
R J
RJ
D000818:Animals; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000494:pharmacology; D017869:Cyclic GMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005978:Glutathione / Q000031:analogs & derivatives / Q000494:pharmacology; D006162:Guanylate Cyclase / Q000037:antagonists & inhibitors; D006372:Helix, Snails; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism*; D009599:Nitroprusside / Q000494:pharmacology; D009603:Nitroso Compounds / Q000494:pharmacology; D009842:Oligopeptides / Q000378:metabolism / Q000494:pharmacology*; D010069:Oxadiazoles / Q000494:pharmacology; D010396:Penicillamine / Q000031:analogs & derivatives / Q000494:pharmacology; D011810:Quinoxalines / Q000494:pharmacology; D026422:S-Nitrosoglutathione; D012977:Sodium Nitrite / Q000494:pharmacology
C095284:1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one; D004791:Enzyme Inhibitors; D009603:Nitroso Compounds; D009842:Oligopeptides; D010069:Oxadiazoles; D011810:Quinoxalines; C110881:S-nitro-N-acetylpenicillamine; D009599:Nitroprusside; C016276:8-bromocyclic GMP; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione; D017869:Cyclic GMP-Dependent Protein Kinases; D006162:Guanylate Cyclase; D005978:Glutathione; D010396:Penicillamine; D006152:Cyclic GMP; D012977:Sodium Nitrite; D019331:NG-Nitroarginine Methyl Ester