title: [Chinfloxacin hydrochloride inhibits HERG potassium channel at open state].
abstract: This study is designed to investigate the effects of chinfloxacin hydrochloride (CFX) on the kinetics of HERG K+ channel. Whole cell patch clamp technique was used to record HERG K+ currents from HEK293 cells transiently transfected with cgi-HERG-GFP plasmids and channel kinetics were assessed in the absence and presence of CFX and moxifloxacin hydrochloride (MOX). Results demonstrated that the open state of HERG K+ channel was inhibited by CFX in a concentration- and time-dependent manner, with an IC50 of 162.1 +/- 14.2 micromol x L(-1), two folds higher than its positive control MOX. But there were no significant effects on channel kinetics. In addition, the inhibitory effect of CFX on HERG was enhanced when cells were subjected to altered extracellular K+ concentration.
authors.affiliation: Jiangsu Key Laboratory for Molecular and Medical Biotechnology, Nanjing Normal University, Nanjing 210046, China.
authors.forename: Xiang-mei
authors.initials: XM
authors.lastname: Zhang
authors.forename: Zhong-hua
authors.initials: ZH
authors.lastname: Zhu
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Sun
authors.forename: Jia
authors.initials: J
authors.lastname: Guo
authors.forename: Zhong-zhong
authors.initials: ZZ
authors.lastname: Zhao
authors.forename: Zhao
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D001372:Aza Compounds / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D051638:Ether-A-Go-Go Potassium Channels / Q000037:antagonists & inhibitors* / Q000502:physiology*; D024841:Fluoroquinolones / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D057809:HEK293 Cells; D006801:Humans; D020128:Inhibitory Concentration 50; D007700:Kinetics; D015394:Molecular Structure; D000077266:Moxifloxacin; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000494:pharmacology; D011804:Quinolines / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection
chemical_list: D000900:Anti-Bacterial Agents; D001372:Aza Compounds; D051638:Ether-A-Go-Go Potassium Channels; D024841:Fluoroquinolones; D011804:Quinolines; C577146:chinfloxacin; D011188:Potassium; D000077266:Moxifloxacin