Influence of Thromboxane A₂ on the Regulation of Adenosine Triphosphate-Sensitive Potassium Channels in Mouse Ventricular Myocytes
Korean Circulation Journal
; : 562-568, 2016.
Article
in En
| WPRIM
| ID: wpr-134748
Responsible library:
WPRO
ABSTRACT
BACKGROUND AND OBJECTIVES: Adenosine triphosphate (ATP)-sensitive potassium (K(ATP)) channels play an important role in myocardial protection. We examined the effects of thromboxane A₂ on the regulation of K(ATP) channel activity in single ventricular myocytes. SUBJECTS AND METHODS: Single ventricular myocytes were isolated from the hearts of adult Institute of Cancer Research (ICR) mice by enzymatic digestion. Single channel activity was recorded by excised inside-out and cell-attached patch clamp configurations at -60 mV holding potential during the perfusion of an ATP-free K-5 solution. RESULTS: In the excised inside-out patches, the thromboxane A₂ analog, U46619, decreased the K(ATP) channel activity in a dose-dependent manner; however, the thromboxane A₂ receptor antagonist, SQ29548, did not significantly attenuate the inhibitory effect of U46619. In the cell-attached patches, U46619 inhibited dinitrophenol (DNP)-induced K(ATP) channel activity in a dose-dependent manner, and SQ29548 attenuated the inhibitory effects of U46619 on DNP-induced K(ATP) channel activity. CONCLUSION: Thromboxane A₂ may inhibit K(ATP) channel activity, and may have a harmful effect on ischemic myocardium.
Key words
Full text:
1
Database:
WPRIM
Main subject:
Perfusion
/
Potassium
/
Potassium Channels
/
Adenosine
/
Adenosine Triphosphate
/
15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid
/
Muscle Cells
/
Digestion
/
KATP Channels
/
Heart
Type of study:
Diagnostic_studies
Limits:
Animals
/
Humans
Language:
En
Journal:
Korean Circulation Journal
Year:
2016
Document type:
Article