title: Effect of calcitonin gene-related peptide on gonadotrophin-releasing hormone mRNA expression in GT1-7 cells.
abstract: Recent evidence has shown calcitonin gene-related peptide (CGRP) to be a key mediator of stress-induced suppression of the gonadotrophin-releasing hormone (GnRH) pulse generator, although little is known about the neural pathways involved. In the present study, we investigated the potential direct action of CGRP on GnRH neurones using GT1-7 cells, an established GnRH cell line. First, we detected expression of the CGRP receptor subunits, calcitonin receptor-like receptor and receptor activity-modifying protein-1 in the GT1-7 cells by reverse transcriptase-polymerase chain reaction. Second, we have shown that CGRP inhibits GnRH mRNA expression in the GT1-7 cells, which was effectively reversed by the CGRP receptor antagonist, CGRP8-37. These results suggest that CGRP down regulates expression of GnRH mRNA, via CGRP receptors in the GT1-7 cell, thus implying that a potential direct action of CGRP may mediate a suppressive effect on the GnRH neural network.
authors.affiliation: Division of Reproductive Health, Endocrinology and Development, King's College London, UK.
authors.forename: J S
authors.initials: JS
authors.lastname: Kinsey-Jones
authors.forename: X F
authors.initials: XF
authors.lastname: Li
authors.forename: J E
authors.initials: JE
authors.lastname: Bowe
authors.forename: S D
authors.initials: SD
authors.lastname: Brain
authors.forename: S L
authors.initials: SL
authors.lastname: Lightman
authors.forename: K T
authors.initials: KT
authors.lastname: O'Byrne
mesh_terms: D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology*; D002460:Cell Line; D003864:Depression, Chemical; D015870:Gene Expression / Q000187:drug effects; D007987:Gonadotropin-Releasing Hormone / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000096:biosynthesis; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis*; D058261:Receptor Activity-Modifying Proteins; D018015:Receptors, Calcitonin Gene-Related Peptide / Q000187:drug effects / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D012333:RNA, Messenger; D058261:Receptor Activity-Modifying Proteins; D018015:Receptors, Calcitonin Gene-Related Peptide; D007987:Gonadotropin-Releasing Hormone; D015740:Calcitonin Gene-Related Peptide