Muscarinic receptor heterogeneity in guinea pig intestinal smooth muscle: binding studies with AF-DX 116

E Giraldo1, E Monferini, H Ladinsky

  • 1Department of Biochemistry, Istituto De Angeli, Milan, Italy.

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Cholinergic antagonists—such as antimuscarinics—are available in oral, topical, ocular, parenteral, and inhalational formulations. Most antimuscarinics are oral formulations,  while scopolamine is available as a topical patch, and ipratropium and tiotropium are available as inhalation aerosols or powders. Atropine, tropicamide, and cyclopentolate are topically instilled in the eye. Most antimuscarinics are lipid-soluble and readily absorbed from the gastrointestinal tract and the conjunctiva.
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