Glibenclamide specifically blocks ATP-sensitive K+ channel current in atrial myocytes of guinea pig heart.
Effects of glibenclamide on the control membrane ionic currents, acetylcholine or adenosine-induced K+ current, and nicorandil-induced K+ current were examined in single atrial myocytes of guinea pig heart. The nystatin-whole cell clamp technique was used. Nicorandil evoked the time-independent K+ current which is probably the current through the ATP-sensitive K+ channel. Glibenclamide inhibited this current in a concentration-dependent fashion, although it had no effect on the other currents. We concluded that glibenclamide specifically inhibits the ATP-sensitive K+ channel current in cardiac myocytes.
Hamada
E
E
Second Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Takikawa
R
R
Ito
H
H
Iguchi
M
M
Terano
A
A
Sugimoto
T
T
Kurachi
Y
Y
D000255:Adenosine Triphosphate / Q000502:physiology; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005905:Glyburide / Q000494:pharmacology*; D006168:Guinea Pigs; D006325:Heart Atria / Q000166:cytology / Q000187:drug effects; D008564:Membrane Potentials / Q000187:drug effects; D009206:Myocardium / Q000166:cytology*; D015221:Potassium Channels / Q000187:drug effects*
D015221:Potassium Channels; D000255:Adenosine Triphosphate; D005905:Glyburide