title: Muscarinic acetylcholine receptors on an identified motor neurone in the cockroach, Periplaneta americana.
abstract: Muscarinic acetylcholine receptors (mAChRs) on the cell body of the fast coxal depressor motor neurone (Df) in the metathoracic ganglion of the cockroach Periplaneta americana were investigated using electrophysiological methods. Muscarinic agonists, arecoline and oxotremorine, induced dose-dependent depolarizations on motor neurone Df. McN-A-343, a vertebrate mAChR M1 subtype-selective agonist, failed to induce any responses when tested on the same neurone at concentrations of up to 1.0 x 10(-4) M. The order of effectiveness of a series of muscarinic antagonists on the mAChRs of motor neurone Df is as follows: scopolamine > atropine > pirenzepine. 4-DAMP (1.0 x 10(-5) M) had only a weak blocking effect and AF-DX 116 (1.0 x 10(-5) M) was completely inactive. The pharmacological profile of muscarinic responses on motor neurone Df reveals a novel type of insect mAChR.
authors.affiliation: AFRC Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, UK.
authors.forename: D
authors.initials: D
authors.lastname: Bai
authors.forename: D B
authors.initials: DB
authors.lastname: Sattelle
mesh_terms: D008455:(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride / Q000494:pharmacology; D000818:Animals; D001115:Arecoline / Q000494:pharmacology; D001285:Atropine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005071:Evoked Potentials / Q000187:drug effects; D017952:Ganglia, Invertebrate / Q000502:physiology; D066298:In Vitro Techniques; D008297:Male; D009046:Motor Neurons / Q000187:drug effects / Q000502:physiology*; D018721:Muscarinic Agonists / Q000494:pharmacology*; D018727:Muscarinic Antagonists / Q000494:pharmacology*; D010095:Oxotremorine / Q000494:pharmacology; D010526:Periplaneta; D010880:Piperidines / Q000494:pharmacology; D010890:Pirenzepine / Q000031:analogs & derivatives / Q000494:pharmacology; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000502:physiology*; D012601:Scopolamine / Q000494:pharmacology; D014714:Vertebrates
chemical_list: D018721:Muscarinic Agonists; D018727:Muscarinic Antagonists; D010880:Piperidines; D011976:Receptors, Muscarinic; D010890:Pirenzepine; D001115:Arecoline; D008455:(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride; D010095:Oxotremorine; D001285:Atropine; C042375:4-diphenylacetoxy-1,1-dimethylpiperidinium; D012601:Scopolamine; C048593:otenzepad