Anticholinergic effects of artemisinin, an antimalarial drug, in isolated guinea pig heart preparations
Language: 
English
Abstract: 

Concern has been growing about the cardiac toxicity of antimalarial drugs. Artemisinin, a unique type of antimalarial drug originating from a Chinese medicinal plant, has minimal adverse effects, but it has been reported to inhibit delayed rectifier potassium current, a voltage-gated potassium current. However, no studies have been published concerning the effect of artemisinin on ligand-gated potassium currents. Therefore, in the present study, we examined the influence of artemisinin on the acetylcholine receptor-operated potassium current (IK.ACh), a ligand-gated potassium current, in guinea pig atrial myocytes using a patch clamp technique. Artemisinin (1 to 300 microM) inhibited I(K.ACh) induced by extracellular application of both carbachol (1 microM) and adenosine (10 microM) and that induced by intracellular loading of GTPgammaS (100 microM) in a concentration-dependent manner. Artemisinin inhibited carbachol-induced, adenosine-induced, and GTPgammaS-activated IK.ACh within almost the same concentration range. In left atria, artemisinin (1 to 100 microM) partially reversed the shortening of action potential duration induced by carbachol in a concentration-dependent manner. Carbachol-induced negative inotropic action in left atria was also inhibited by artemisinin (10 to 300 microM). In conclusion, we suggest that the anticholinergic action of artemisinin is mediated through inhibition of IK.ACh via inhibition of the muscarinic potassium channel and/or associated GTP-binding proteins.

Author(s): 
Hara, Yukio
Yamawaki, Hideyuki
Shimada, Masami
Okada, Kiyohiro
Tanai, Toshiki
Ichikawa, Daiki
Miyake, Kimihito
Kizaki, Keiichiro
Item Type: 
Journal Article
Publication Title: 
The Journal of Veterinary Medical Science / the Japanese Society of Veterinary Science
Journal Abbreviation: 
J. Vet. Med. Sci.
Publication Date: 
7/7/2015
Publication Year: 
2007
Pages: 
697-702
Volume: 
69
Issue: 
7
ISSN: 
0916-7250
Library Catalog: 
PubMed
Extra: 
PMID: 17675799

Turabian/Chicago Citation

Yukio Hara, Hideyuki Yamawaki, Masami Shimada, Kiyohiro Okada, Toshiki Tanai, Daiki Ichikawa, Kimihito Miyake and Keiichiro Kizaki. 7/7/2015. "Anticholinergic effects of artemisinin, an antimalarial drug, in isolated guinea pig heart preparations." The Journal of Veterinary Medical Science / the Japanese Society of Veterinary Science 69: 7: 697-702.

Wikipedia Citation

<ref> {{Cite journal | doi = | issn = 0916-7250 | volume = 69 | pages = 697-702 | last = Hara | first = Yukio | coauthors = Yamawaki, Hideyuki, Shimada, Masami, Okada, Kiyohiro, Tanai, Toshiki, Ichikawa, Daiki, Miyake, Kimihito, Kizaki, Keiichiro | title = Anticholinergic effects of artemisinin, an antimalarial drug, in isolated guinea pig heart preparations | journal = The Journal of Veterinary Medical Science / the Japanese Society of Veterinary Science | date = 7/7/2015 | pmid = | pmc = }} </ref>