Effects of cyclovirobuxine D on intracellular Ca2+ and L-type Ca2+ current in rat ventricular cardiomyocytes.
- Author:
Qing-Wen CHEN
1
;
Hong-Li SHAN
;
Hong-Li SUN
;
He WANG
;
Bao-Feng YANG
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Buxus; chemistry; Calcium; metabolism; Calcium Channels, L-Type; drug effects; Cell Separation; Drugs, Chinese Herbal; isolation & purification; pharmacology; Female; Heart Ventricles; cytology; Male; Myocytes, Cardiac; metabolism; Plants, Medicinal; chemistry; Rats; Rats, Wistar
- From: Acta Pharmaceutica Sinica 2004;39(7):500-503
- CountryChina
- Language:Chinese
-
Abstract:
AIMTo determine the effects of cyclovirobuxine D (CD) on intracellular Ca2+ mobilization and L-type Ca2+ current (I(Ca-L)) in isolated rat cardiomyocytes.
METHODSThe effects of CD on the amplitude of I(Ca-L) and intracellular Ca2+ mobilization induced by KCl and caffeine were studied with the method of patch-clamp technique and laser scanning confocal microscopy in rat ventricular myocytes.
RESULTSCD decreased the amplitude of I(Ca-L) in a concentration-dependent manner. At 10 mV, 1 and 10 micromol x L(-1) CD decreased I(Ca-L) density from (- 9.9 +/- 1.8) pA/pF to (-6.4 +/- 1.4) and (-4.2 +/- 0.6) pA/pF, respectively. Confocal experiments showed that intracellular fluorescent intensity (FI) value of [Ca2+] in control resting level was not changed by 1 and 10 micromol x L(-1) CD. [Ca2+] increase in response to KCl could not be reduced by CD. The rise of [Ca2+]i in response to caffeine was further enhanced by pretreatment with CD.
CONCLUSIONCD decreased I(Ca,L) in a concentration-dependent manner and increased [Ca2+]i release induced by caffeine in rat ventricular cardiomyocytes.
