Immunohistochemical localization and electrophysiological action of nociceptin/orphanin-FQ in the snail (Helix aspersa) neurons.
We report the existence and anatomical distribution to nociceptin/orphanin-FQ (N/O FQ)-like immunoreactivity in neurons and fibers in the perioesophageal ganglia of the snail (Helix aspersa). Intracellular recordings from perioesophageal ganglion neurons showed that the application of 10 microM N/O FQ produced an excitatory action in 22% of the neurons studied and an inhibitory action in 33% of the neurons regardless of their origin (cerebral or parietal ganglion). Our result provides evidence that N/O FQ-like peptide is located in whole perioesophageal ganglia (mainly in the cerebral one), and that it may serve as a neuromodulator of the neuronal spike discharge. These data support the idea that the N/O FQ opioid system has an early phylogenetic origin and a functional continuity during the course of evolution.
León-Olea
M
M
Instituto Nacional de Psiquiatría "Ramón de la Fuente", Av. México-Xochimilco 101, CP 14370, México DF, Mexico.
Miller-Pérez
C
C
Cruz
R
R
Antón
B
B
Vega
R
R
Soto
E
E
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001921:Brain / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D017952:Ganglia, Invertebrate / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D006372:Helix, Snails / Q000166:cytology / Q000378:metabolism*; D007150:Immunohistochemistry; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D018847:Opioid Peptides / Q000378:metabolism* / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D000097629:Nociceptin
D018847:Opioid Peptides; D000097629:Nociceptin