ELECTROPHYSIOLOGICAL EFFECTS OF CHANGROLIN, AN ANTIARRHYTHMIC AGENT DERIVED FROM DICHROA FEBRIFUGA, ON GUINEA-PIG AND RABBIT HEART CELLS
| Autor: | Ling-Ling Lu, Hideo Tanaka, Junichiro Morikawa, Yoshizumi Habuchi |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Patch-Clamp Techniques
Physiology Heart Ventricles Voltage clamp medicine.medical_treatment Guinea Pigs Action Potentials Antiarrhythmic agent Pharmacology Guinea pig Species Specificity Physiology (medical) medicine Animals Ventricular Function Heart Atria Cardiac transient outward potassium current Ion Transport Dose-Response Relationship Drug biology Chemistry Inward-rectifier potassium ion channel fungi Changrolin food and beverages Heart Dichroa febrifuga Atrial Function biology.organism_classification Electric Stimulation Electrophysiology Potassium Quinazolines Rabbits Anti-Arrhythmia Agents Drugs Chinese Herbal |
| Zdroj: | Clinical and Experimental Pharmacology and Physiology. 22:337-341 |
| ISSN: | 1440-1681 0305-1870 |
| DOI: | 10.1111/j.1440-1681.1995.tb02011.x |
| Popis: | SUMMARY 1. The electrophysiological effects of changrolin (CRL), a Chinese antiarrhythmic drug derived from a traditional anti-malarial plant, were examined using the whole-cell patch-clamp method on single cells isolated from guinea-pig and rabbit hearts. 2. At a clinically relevant concentration of 50μmol/L changrolin inhibited Ica. by 19.3 ± 6.0% and 17.3 ± 2.6% in guinea-pig and rabbit ventricular cells, respectively. The voltage-dependent channel availability curve was not affected. The CRL effect was enhanced to a small extent during a repetitive stimulation at 2 Hz. 3. Ina was resistant to CRL and the channel availability curve was also unaffected. A small use-dependent inhibition was observed only when the Ina was elicited at 5 Hz in the presence of 300 μmol/L CRL. 4. At 50 μmol/L, CRL did not affect the time-independent inward rectifier and the delayed rectifier K+ currents (Iki and Ik, respectively), but inhibited the transient outward current (Ito) by 17.7 ± 2.4%. Changrolin significantly shortened the action potential duration in both guinea-pig and rabbit ventricular cells. 5. In conclusion, CRL inhibits Ica and Ito but has little effect on Ina. |
| Databáze: | OpenAIRE |
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