Suguro_2010_J.Vet.Med.Sci_72_443

Reference

Title : Muscarinic receptor subtypes mediating Ca2+ sensitization of intestinal smooth muscle contraction: studies with receptor knockout mice - Suguro_2010_J.Vet.Med.Sci_72_443
Author(s) : Suguro M , Matsuyama H , Tanahashi Y , Unno T , Kitazawa T , Yamada M , Komori S
Ref : J Vet Med Sci , 72 :443 , 2010
Abstract :

In the present study, we have characterized muscarinic receptor subtypes that mediate carbachol-induced Ca2+ sensitization of contraction in intestinal smooth muscle, using mutant mice lacking M(2) or M(3) muscarinic receptors or both receptor subtypes. In alpha-toxin-permeabilized muscle strips from wild-type (WT) mice, isometric tension responses to Ca2+ applied cumulatively (pCa 7.0-5.0) were increased when the muscarinic agonist carbachol (100 microM) was added to the medium, as judged from shifts of pCa-tension curves in both 50% effective concentration (EC(50)) and maximum response (E(max)) of pCa-tension curve. In preparations from M(2)-knockout (KO) mice, pCa-tension curves were also shifted by carbachol (100 microM), and the extents of the EC(50) and E(max) changes resembled those observed in preparations from WT mice. In preparations from M(3)-KO or M(2)/M(3)-double KO mice, however, no significant changes in pCa-tension curves were obtained after carbachol application. The G(q/11)-type G-protein inhibitor YM-254890 (1 microM) completely blocked the Ca2+ sensitization of contraction induced by carbachol in M(2)-KO or WT preparations. The results strongly support the idea that the muscarinic activation of Ca2+ sensitization in intestinal smooth muscles is mediated by the M(3) muscarinic receptor coupled to G(q/11)-type G-proteins, without any significant involvement of the other muscarinic receptor subtypes including M(2).

PubMedSearch : Suguro_2010_J.Vet.Med.Sci_72_443
PubMedID: 20009428

Related information

Citations formats

Suguro M, Matsuyama H, Tanahashi Y, Unno T, Kitazawa T, Yamada M, Komori S (2010)
Muscarinic receptor subtypes mediating Ca2+ sensitization of intestinal smooth muscle contraction: studies with receptor knockout mice
J Vet Med Sci 72 :443

Suguro M, Matsuyama H, Tanahashi Y, Unno T, Kitazawa T, Yamada M, Komori S (2010)
J Vet Med Sci 72 :443