title: The nociceptin/orphanin FQ-like opioid peptide in nervous periesophageal ganglia of land snail Helix aspersa.
abstract: The neuropeptide nociceptin/orphanin FQ (N/OFQ) and its receptor are members of the endogenous opioid peptide family. In mammals N/OFQ modulates a variety of biological functions such as nociception, food intake, endocrine, control of neurotransmitter release, among others. In the molluscs Cepea nemoralis and Helix aspersa the administration of N/OFQ produces a thermopronociceptive effect. However, little is known about its existence and anatomic distribution in invertebrates. The aim of this study was to provide a detailed anatomical distribution of N/OFQ like peptide immunoreactivity (N/OFQ-IL), to quantify the tissue content of this peptide, as well as to demostrate molecular evidence of N/OFQ mRNA in the nervous tissue of periesophageal ganglia of the land snail H. aspersa. Immunohistochemical, immunocytochemical, radioimmunoanalysis (RIA) and reverse transcription-polymerase chain reaction (RT-PCR) techniques were used. With regard to RT-PCR, the primers to detect expression of mRNA transcripts from H. aspersa were derived from the rat N/OFQ opioid peptide. We show a wide distribution of N/OFQ-IL in neurons and fibers in all perioesophageal ganglia, fibers of the neuropile, nerves, periganglionar connective tissue, aortic wall and neurohemal sinuses. The total amount of N/OFQ-IL in the perioesophageal ganglia (7.75 ± 1.75 pmol/g of tissue) quantified by RIA was similar to that found in mouse hypothalamus (10.1 ± 1.6 pmol/g of tissue). In this study, we present molecular evidence of N/OFQ mRNA expression. Some N/OFQ-IL neurons have been identified as neuroendocrine or involved in olfaction, hydro-electrolyte regulation, feeding, and thermonociception. Therefore, we suggest that N/OFQ may participate in these snail functions.
authors: Departamento de Neuromorfología Funcional, Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz. Av. México Xochimilco 101, Col. San Lorenzo Huipulco, México D.F., C.P. 14370, México. marthalo@imp.edu.mx
authors: Martha
authors: M
authors: León-Olea
authors: Carolina
authors: C
authors: Miller-Pérez
authors: Eduardo
authors: E
authors: Sánchez-Islas
authors: José
authors: J
authors: Mendoza-Sotelo
authors: René
authors: R
authors: Garduño-Gutiérrez
authors: Patricia
authors: P
authors: de Gortari
authors: María Isabel
authors: MI
authors: Amaya
mesh_terms: D000818:Animals; D002490:Central Nervous System / Q000166:cytology; D004745:Enkephalins / Q000378:metabolism; D017952:Ganglia, Invertebrate / Q000166:cytology* / Q000378:metabolism; D006372:Helix, Snails; D046529:Microscopy, Electron, Transmission; D009412:Nerve Fibers / Q000378:metabolism / Q000648:ultrastructure; D018847:Opioid Peptides / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011984:Sensory Receptor Cells / Q000378:metabolism* / Q000648:ultrastructure; D000097629:Nociceptin
chemical_list: D004745:Enkephalins; D018847:Opioid Peptides; D012333:RNA, Messenger; D000097629:Nociceptin