| Autor: |
Hayato Matsuyama, Yasuyuki Tanahashi, Takio Kitazawa, Masahisa Yamada, Seiichi Komori, Toshihiro Unno |
| Jazyk: |
angličtina |
| Rok vydání: |
2013 |
| Předmět: |
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| Zdroj: |
Journal of Pharmacological Sciences, Vol 121, Iss 3, Pp 227-236 (2013) |
| Druh dokumentu: |
article |
| ISSN: |
1347-8613 |
| DOI: |
10.1254/jphs.12231FP |
| Popis: |
Cholinergic nerve–mediated excitatory junction potentials (EJPs) in the longitudinal muscle of mouse ileum were characterized by using M2 or M3 muscarinic receptor–knockout (KO) mice and 1-[β-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl]-1H-imidazole hydrochloride (SK&F 96365) and pertussis toxin (PTX). EJPs evoked by electrical field stimulation (EFS) in wild-type preparations, initially determined to be cholinergic in origin using tetrodotoxin, atropine, and eserine, were profoundly depressed after SK&F 96365 treatment known to block muscarinic receptor–operated cation channels. A similar depression of the EJPs was also observed by PTX treatment, which is predicted to disrupt M2-mediated pathways linked to cation channel activation. In M2-KO mouse preparations, cholinergic EJPs were evoked by EFS with their relative amplitude of 20% – 30% to the wild-type EJP and strongly inhibited by SK&F 96365. No cholinergic EJP was seen in M3-KO as well as M2/M3 double-KO preparations. The results suggest that the wild-type cholinergic EJP is not a simple mixture of M2 and M3 responses, but due to synergistic activation of cation channels by both M2 and M3 receptors in the murine ileal longitudinal muscle. Keywords:: muscarinic receptor, smooth muscle, nonselective cation channel, excitatory junction potential (EJP), small intestine |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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