Arenobufagin, a compound in toad venom, blocks Na(+)-K+ pump current in cardiac myocytes.
The effects of arenobufagin, a bufadienolide isolated from toad venom, on the Na+/K+ pump were investigated by recording the whole-cell current of dissociated cardiac myocytes. Arenobufagin blocked the Na+/K+ pump current in a dose-dependent manner with a half-maximal concentration of 0.29 microM and a Hill coefficient of 1.1. Arenobufagin is 3.5-fold more potent than ouabain.
Cruz
J dos S
Jdos S
Department of Physiology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Matsuda
H
H
D000818:Animals; D002018:Bufanolides / Q000494:pharmacology*; D004553:Electric Conductivity; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects; D066298:In Vitro Techniques; D009206:Myocardium / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors / Q000187:drug effects*
D002018:Bufanolides; C055393:arenobufagin; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium