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Activation of the K+ channel BKCa is involved in the relaxing effect of propofol on coronary arteries

  • A. P. Klockgether-Radke (a1), H. Schulze (a1), P. Neumann (a1) and G. Hellige (a1)



Background and objective: Propofol may cause undesirable hypotension due to vasodilation. The underlying mechanisms are not completely understood. We investigated the mechanisms by which propofol relaxes vascular segments.

Methods: We studied the effect of propofol on isolated porcine coronary artery rings precontracted with potassium chloride or prostaglandin F.

Results: Propofol, in a concentration-dependent manner, relaxed all segments at concentrations of 5 μg mL−1 and above. This relaxation was unaltered in the presence of Nω-nitro-L-arginine, indomethacin, diltiazem and glibenclamide. Tetraethylammonium chloride, an inhibitor of the BKCa K+ channel (a high conductance Ca2+-sensitive K+ channel), dose-dependently attenuated the vasodilating effect of propofol (P < 0.001).

Conclusions: Our results suggests that the activation of the BKCa channel may contribute to the vasodilating effect of propofol, hereby causing hyperpolarization of the smooth muscle membrane and reduction of smooth muscle tone.


Corresponding author

Correspondence to: Adelbert Peter Klockgether-Radke, Department of Anaesthesiological Research, Centre of Anaesthesiology, Emergency and Intensive Care Medicine, Georg-August University of Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany. E-mail:; Tel: +49 5561 73066; Fax: +49 5561 73917


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Activation of the K+ channel BKCa is involved in the relaxing effect of propofol on coronary arteries

  • A. P. Klockgether-Radke (a1), H. Schulze (a1), P. Neumann (a1) and G. Hellige (a1)


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