Effects of matrine, artemisinin, tetrandrine on cytosolic [Ca2+]i in guinea pig ventricular myocytes.
OBJECTIVE
To compare the effects of matrine, artemisinin, and tetrandrine on intracellular Ca2+ concentration ([Ca2+]i) in guinea pig ventricular myocytes.


METHODS
A single ventricular myocyte was loaded with Fluo 3-acetoxymethyl (Fluo 3-AM). [Ca2+]i was recorded by laser scanning confocal microscope and represented by fluorescence intensity (FI).


RESULTS
1) KCl 60 mmol . L-1 elevated the FI from 299 +/ -19 to 1389 +/- 325 (P < 0.01) in the presence of extracellular Ca2+ 1.8 mmol . L-1. 2) Both matrine and artemisinin at the concentration of 100 micromol . L-1 could enhance the increase of FI by KCl 60 mmol . L-1. The FI values reached 1495 +/- 320 and 1646 +/- 308 from 301 +/- 14 and 299 +/- 16 (P < 0.01), respectively. 3) Both tetrandrine 1, 10, and 100 micromol . L-1 and verapamil 10 micromol . L-1 inhibited the influx of extracellular Ca2+ induced by KCl 60 mmol . L-1. 4) Matrine 1, 10, and 100 micromol . L-1 could elevate the FI in the presence of extracellular Ca2+. The FI values reached 441 +/- 96, 504 +/- 112, and 643 +/- 126 from 303 +/- 27, 300 +/- 32, and 296 +/- 19 (P < 0.05), respectively. 5) Tetrandrine 1 and 10 micromol . L-1 could apparently inhibited Ca2+ release from intracellular calcium stores induced by caffeine 20 mmol . L-1 (P < 0.05).


CONCLUSIONS
Effects of matrine, artemisinin, and tetrandrine on [Ca2+ )]i in ventricular
Ai
J
J
Department of Pharmacology, Harbin Medical University, Harbin 150086, China Yangbf@ems.hrbmu.edu.cn
Gao
H H
HH
He
S Z
SZ
Wang
L
L
Luo
D L
DL
Yang
B F
BF
D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D037621:Artemisinins / Q000494:pharmacology*; D044182:Benzylisoquinolines; D001693:Biological Transport, Active; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002469:Cell Separation; D006168:Guinea Pigs; D006352:Heart Ventricles / Q000166:cytology / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism*; D011807:Quinolizines; D012717:Sesquiterpenes / Q000494:pharmacology*; D000093842:Matrines
D000470:Alkaloids; D000889:Anti-Arrhythmia Agents; D037621:Artemisinins; D044182:Benzylisoquinolines; D002121:Calcium Channel Blockers; D011807:Quinolizines; D012717:Sesquiterpenes; C009438:tetrandrine; C031327:artemisinin; D002118:Calcium; D000093842:Matrines