title: Binding profile of the selective muscarinic receptor antagonist tripitramine.
abstract: The binding selectivity of the muscarinic antagonist tripitramine has been tested on the five cloned human muscarinic receptor subtypes (Hm1 to Hm5) expressed in chinese hamster ovary (CHO-K1) cells. The results indicate that tripitramine binds to the muscarinic Hm2 receptor with a Ki value of 0.27 +/- 0.02 nM. Tripitramine distinguishes Hm2 vs. Hm4 by a factor of 24 and vs. Hm3 and Hm5 by a factor of 142 and 125, respectively. A lower affinity ratio, about 6-fold, was found between muscarinic Hm2 and Hm1 receptors. A comparative study with the well-known selective muscarinic M2 receptor antagonist methoctramine indicates that tripitramine has gained both potency and selectivity for the muscarinic Hm2 receptor subtype.
authors: Institute of Pharmacology School of Medicine, University of Pisa, Italy.
authors: R
authors: R
authors: Maggio
authors: P
authors: P
authors: Barbier
authors: M L
authors: ML
authors: Bolognesi
authors: A
authors: A
authors: Minarini
authors: D
authors: D
authors: Tedeschi
authors: C
authors: C
authors: Melchiorre
mesh_terms: D000818:Animals; D001569:Benzodiazepines / Q000378:metabolism*; D016466:CHO Cells; D006224:Cricetinae; D018076:DNA, Complementary / Q000378:metabolism; D003959:Diamines / Q000378:metabolism; D006801:Humans; D008024:Ligands; D018727:Muscarinic Antagonists; D019832:N-Methylscopolamine; D010276:Parasympatholytics / Q000378:metabolism; D011976:Receptors, Muscarinic / Q000235:genetics / Q000378:metabolism*; D012602:Scopolamine Derivatives / Q000493:pharmacokinetics; D013816:Thermodynamics
chemical_list: D018076:DNA, Complementary; D003959:Diamines; D008024:Ligands; D018727:Muscarinic Antagonists; D010276:Parasympatholytics; D011976:Receptors, Muscarinic; D012602:Scopolamine Derivatives; D001569:Benzodiazepines; C084480:tripitramine; C054938:methoctramine; D019832:N-Methylscopolamine