title: [3H]Pirenzepine identifies putative M1 muscarinic receptors in human stellate ganglia.
abstract: The specific binding of [3H]pirenzepine ( [3H]PZ) and [3H](-) quinuclidinyl benzilate ( [3H](-)QNB) was investigated in homogenates of human stellate ganglia. [3H]PZ saturation isotherms yielded a Kd of 14 nM and Bmax of 16.7 fmol/mg protein, while [3H](-)QNB binding curves yielded a Kd of 59 pM and Bmax of 33.0 fmol/mg protein. This represents the greatest proportion of high affinity [3H]PZ labeling, relative to [3H](-)QNB, seen in any peripheral tissue examined thus far.
mesh_terms: D000328:Adult; D000368:Aged; D001570:Benzodiazepinones / Q000378:metabolism*; D001665:Binding Sites; D006801:Humans; D008875:Middle Aged; D010890:Pirenzepine; D011813:Quinuclidinyl Benzilate / Q000378:metabolism; D011976:Receptors, Muscarinic / Q000378:metabolism*; D013233:Stellate Ganglion / Q000378:metabolism*
chemical_list: D001570:Benzodiazepinones; D011976:Receptors, Muscarinic; D010890:Pirenzepine; D011813:Quinuclidinyl Benzilate