title: Regulation of myometrial contraction by ATP-sensitive potassium (KATP) channel via activation of SUR2B and Kir 6.2 in mouse.
abstract: ATP-sensitive potassium (KATP) channels are well characterized in cardiac, pancreatic and many other muscle cells. In the present study, functional expression of the KATP channel was examined in non-pregnant murine longitudinal myometrium. Isometric contraction measurements and Western blot were used. KATP channel openers (KCOs), such as pinacidil, cromakalim, diazoxide and nicorandil, inhibited spontaneous myometrial contractions in a reversible and glibenclamide-sensitive manner. KCOs inhibited oxytocin (OXT)- and prostaglandin F2α (PGF2α)-induced phasic contractions in a glibenclamide-sensitive manner. SUR2B and Kir6.2 were detected by Western blot, whereas SUR1, SUR2A and Kir6.1 were not. These results show that pinacidl, cromakalim, diazoxide and nicorandil-sensitive KATP channels exist in murine myometrium, which are composed of SUR2B and Kir6.2. Based on the modulatory effects of the KATP channel on spontaneous contraction, OXT- and PGF2α-induced contractions, KATP channels seem to play an essential role in murine myometrial motility via activation of SUR2B and Kir6.2.
authors.affiliation: Department of Obstetrics and Gynecology, Chungbuk National University (CBNU), Chungdae-ro 1, Seowon-gu, Cheongju, Chungbuk, 28644, Korea.
authors.forename: Seung Hwa
authors.initials: SH
authors.lastname: Hong
authors.forename: Kyu-Sang
authors.initials: KS
authors.lastname: Kyeong
authors.forename: Chan Hyung
authors.initials: CH
authors.lastname: Kim
authors.forename: Young Chul
authors.initials: YC
authors.lastname: Kim
authors.forename: Woong
authors.initials: W
authors.lastname: Choi
authors.forename: Ra Young
authors.initials: RY
authors.lastname: Yoo
authors.forename: Hun Sik
authors.initials: HS
authors.lastname: Kim
authors.forename: Yeon Jin
authors.initials: YJ
authors.lastname: Park
authors.forename: Il Woon
authors.initials: IW
authors.lastname: Ji
authors.forename: Eun-Hwan
authors.initials: EH
authors.lastname: Jeong
authors.forename: Hak Soon
authors.initials: HS
authors.lastname: Kim
authors.forename: Wen-Xie
authors.initials: WX
authors.lastname: Xu
authors.forename: Sang Jin
authors.initials: SJ
authors.lastname: Lee
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D015237:Dinoprost / Q000037:antagonists & inhibitors; D005260:Female; D066298:In Vitro Techniques; D007537:Isometric Contraction; D054086:KATP Channels / Q000378:metabolism*; D008813:Mice, Inbred ICR; D020108:Nicorandil / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D024661:Potassium Channels, Inwardly Rectifying / Q000187:drug effects / Q000378:metabolism*; D064233:Sulfonylurea Receptors / Q000378:metabolism*; D014590:Uterine Contraction / Q000187:drug effects; D000099161:Kcnj11 Channel
chemical_list: D000255:Adenosine Triphosphate; D015237:Dinoprost; D054086:KATP Channels; D020108:Nicorandil; D011188:Potassium; D024661:Potassium Channels, Inwardly Rectifying; D064233:Sulfonylurea Receptors; D000099161:Kcnj11 Channel; C577511:Abcc9 protein, mouse