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Updated: Aug 24, 2026

Exploring Arterial Smooth Muscle Kv7 Potassium Channel Function using Patch Clamp Electrophysiology and Pressure Myography
Published on: September 14, 2012
[Activation of Ca(2+)-activated K+ channels by oxyphenamone in rabbit mesenteric vascular smooth muscle cells]
An-long Li1, Zhong-wu Liu, Li-xia Zhu
1Department of Pharmacology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China.
Aim:
To study the effects of oxyphenamone (Oxy) on activation of Ca(2+)-activated K+ channels in rabbit mesenteric vascular smooth muscle cells.
Methods:
To measure the effect of Oxy on the Ca(2+)-activated K+ channel (BK (Ca) channel) activity in rabbit mesenteric vascular smooth muscle cells by using whole cell patch clamp techniques.
Results:
Oxy reversibly increase BK (Ca) channel activity in rabbit mesenteric artery smooth muscle cells. Application of Oxy (0.1 mumol.L-1) to the perfusion solution caused significant increase in outward currents and its effect was completely abolished by washout; The outward currents K+ was inhibited by TEA (7.5 mmol.L-1); Oxy activated the BK (Ca) channel in a dose-dependent manner (0.01-10 mumol.L-1).
Conclusion:
Oxy directly increase the activity of BK (Ca) channel activity in rabbit mesenteric vascular smooth muscle cells in dose-dependent manner.
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