[Activation of Ca(2+)-activated K+ channels by oxyphenamone in rabbit mesenteric vascular smooth muscle cells].
OBJECTIVE
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).


CONCLUSIONS
Oxy directly increase the activity of BK (Ca) channel activity in rabbit mesenteric vascular smooth muscle cells in dose-dependent manner.
Li
An-long
AL
Department of Pharmacology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China.
Liu
Zhong-wu
ZW
Zhu
Li-xia
LX
Zhang
De-chang
DC
Ye
Yi-xin
YX
D000818:Animals; D002316:Cardiotonic Agents / Q000494:pharmacology*; D008638:Mesenteric Arteries / Q000166:cytology; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000502:physiology*; D009930:Organic Chemicals; D018408:Patch-Clamp Techniques; D024681:Potassium Channels, Calcium-Activated / Q000187:drug effects*; D011817:Rabbits
D002316:Cardiotonic Agents; D009930:Organic Chemicals; D024681:Potassium Channels, Calcium-Activated; C442156:oxyphenamone