Effects of matrine, artemisinin, tetrandrine on cytosolic [Ca2+]i in guinea pig ventricular myocytes
Abstract
Aim: 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).
Conclusion: Effects of matrine, artemisinin, and tetrandrine on [Ca2+ )]i in ventricular
Keywords:
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).
Conclusion: Effects of matrine, artemisinin, and tetrandrine on [Ca2+ )]i in ventricular