title: Evidence of muscarinic acetylcholine receptors and GTP-binding proteins in peritoneal mesothelial cells in vitro.
abstract: Preliminary evidence of muscarinic acetylcholine receptors (AchRs) in rabbit and human peritoneal mesothelial cells grown in tissue culture is reported. Atropine displaceable binding of L-quinuclidinyl[phenyl-4-3H]-benzilate (QNB), an antagonist that binds to all AchR subtypes, and [N-methyl-3H]-4-diphenylacetoxy-N-methyl-piperidine methiodide (4-DAMP), an antagonist specific for AchR subtypes 1 and 3, to homogenates of mesothelial cells was approximately 400 and 120 fmol ligand bound/milligram cell protein, respectively. A similar value for specific [3H]-QNB binding was observed in living cells exposed to ligand and atropine for 1 hour at 37C. Guanosine 5'-triphosphate (GTP)-binding proteins measured as beta,gamma-imido[8-3H] guanosine 5'-triphosphate binding to mesothelial cell membranes was approximately 9 pmol/mg cell protein. Our finding of both muscarinic receptors and GTP-binding proteins in mesothelial cells suggests first, the presence of a functional muscarinic receptor system(s) in peritoneal mesothelial cells, and second, the potential susceptibility of these cells to direct pharmacological manipulation by muscarinic drugs.
authors.affiliation: University of Illinois College of Medicine at Peoria.
authors.forename: J T
authors.initials: JT
authors.lastname: Hjelle
authors.forename: A K
authors.initials: AK
authors.lastname: Ho
authors.forename: J W
authors.initials: JW
authors.lastname: Dobbie
authors.forename: K R
authors.initials: KR
authors.lastname: Steidley
authors.forename: R
authors.initials: R
authors.lastname: Duffield
mesh_terms: D000818:Animals; D001285:Atropine / Q000378:metabolism; D001667:Binding, Competitive; D002478:Cells, Cultured; D004848:Epithelium / Q000737:chemistry / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000032:analysis*; D006801:Humans; D010537:Peritoneum / Q000737:chemistry* / Q000378:metabolism; D010880:Piperidines / Q000378:metabolism; D011813:Quinuclidinyl Benzilate / Q000031:analogs & derivatives / Q000378:metabolism; D011817:Rabbits; D011976:Receptors, Muscarinic / Q000032:analysis*
chemical_list: D010880:Piperidines; D011976:Receptors, Muscarinic; C069205:quinuclidinyl-2-thienyl-4-bromobenzilate; D011813:Quinuclidinyl Benzilate; D001285:Atropine; C042375:4-diphenylacetoxy-1,1-dimethylpiperidinium; D019204:GTP-Binding Proteins