Details

Autor(en) / Beteiligte

• Kwak, Yong Geun
• Kim, Dae Keun
• Ma, Tian-Ze
• Park, Sun-Ah
• Park, Hoon
• Jung, Young Hoon
• Yoo, Dong-Jin
• Eun, Jae Soon

Titel

Torilin from Torilis japonica (Houtt.) DC. blocks hKv1.5 channel current

Ist Teil von

• Archives of Pharmacal Research, 2006, 29(10), , pp.834-839

Ort / Verlag

Korea (South): 대한약학회

Erscheinungsjahr

2006

Quelle

MEDLINE

Beschreibungen/Notizen

• Torilin was purified from Torilis japonica (Houtt.) DC., and its effects on a rapidly activating delayed rectifier K+ channel (hKv1.5), cloned from human heart and stably expressed in Ltk- cells, as well as the corresponding K+ current (the ultrarapid delayed rectifier, I(KUR)) were assessed in human atrial myocytes. Using the whole cell configuration of the patch-clamp technique, torilin was found to inhibit the hKv1.5 current in time and voltage-dependent manners, with an IC50 value of 2.51+/-0.34 microM at +60 mV. Torilin accelerated the inactivation kinetics of the hKv1.5 channel, and slowed the deactivation kinetics of the hKv1.5 current, resulting in a tail crossover phenomenon. Additionally, torilin inhibited the hKv1.5 current in a use-dependent manner. These results strongly suggest that torilin is a type of open-channel blocker of the hKv1.5 channel.