title: Functional group I metabotropic glutamate receptors in submucous plexus of guinea-pig ileum.
abstract: Intracellular recording methods and immunostaining revealed the existence of functional group I metabotropic glutamate receptors (mGluRs) in submucous plexus neurons of guinea-pig ileum. Selective group I, but not groups II or III metabotropic glutamate receptor agonists induced concentration-dependent, slowly-activating depolarizing responses. Group I metabotropic glutamate receptor antagonism observed with (S)-4-carboxyphenylglycine (S-4-CPG) (100 - 600 microM) was competitive as determined by Schild analysis (pA(2)=3.81+/-0.02). Neither the group II and III metabotropic nor ionotropic glutamate receptor antagonists altered responses evoked by group I receptor agonists. Immunoreactivities for metabotropic glutamate 1alpha and 5 receptors were found to locate exclusively in neurons in the submucous plexus of guinea-pig ileum with the highest density around the cell bodies. The results suggest that group I metabotropic glutamate receptors are functionally expressed in the submucous plexus of guinea-pig small intestine.
authors.affiliation: Department of Physiology, College of Medicine and Public Health, Ohio State University, 1645 Neil Avenue, 302 Hamilton Hall, Columbus, Ohio, OH 43210-1218, USA.
authors.forename: H Z
authors.initials: HZ
authors.lastname: Hu
authors.forename: J
authors.initials: J
authors.lastname: Ren
authors.forename: S
authors.initials: S
authors.lastname: Liu
authors.forename: C
authors.initials: C
authors.lastname: Gao
authors.forename: Y
authors.initials: Y
authors.lastname: Xia
authors.forename: J D
authors.initials: JD
authors.lastname: Wood
mesh_terms: D000818:Animals; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005998:Glycine / Q000031:analogs & derivatives / Q000494:pharmacology; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects / Q000294:innervation / Q000378:metabolism*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D016318:Quisqualic Acid / Q000494:pharmacology; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate / Q000187:drug effects / Q000378:metabolism*; D012118:Resorcinols / Q000494:pharmacology; D013368:Submucous Plexus / Q000187:drug effects / Q000378:metabolism*
chemical_list: D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate; D012118:Resorcinols; C104077:metabotropic glutamate receptor type 1; C079215:3,5-dihydroxyphenylglycine; D016318:Quisqualic Acid; D005998:Glycine