Aim Intracellular calcium ([Ca^(2+) ]_i) is mainly regulated by mitochondriaand endo-plasmic reticula. This study was carried out to ascertain whether the elementary mechanismof the effects of etimicin (EM) and gentam...Aim Intracellular calcium ([Ca^(2+) ]_i) is mainly regulated by mitochondriaand endo-plasmic reticula. This study was carried out to ascertain whether the elementary mechanismof the effects of etimicin (EM) and gentamicin (GM) on [Ca^(2+) ]_i is related to their effects onmitochondrion Ca^(2+) -uptake and endoplasmic reticulum Ca^(2+) -uptake. Methods The effects of GMand EM on [Ca^(2+) ]_i in LLC-PK1 were determined with a fluorescent probe of Fura-2/AM. The effectsof EM and GM on mitochondrion Ca^(2+) -uptake and endoplasmic reticulum Ca^(2+) -uptake weredetermined by isotope indicator (^(45)Ca^(2+) ) . Results EM and GM at the concentration of 1mmol·L^(-1) had no significant effect on [Ca^(2+) ]_i(P. > 0.05) and at 10 mmol·L^(-1)significantly caused [Ca^(2+) ]_i to increase (P < 0.01). EM and GM at 1 mmol·L^(-1) causedmitochondrion Ca^(2+)-uptake to ascend dramatically (P < 0.05) and at 10 mmol·L^(-1) causedmitochondrion Ca^(2+) -uptake to descend significantly. EM and GM at more than 0.34 mrnol·L^(-1)significantly inhibited endoplasmic reticulum Ca^(2+) -uptake (P < 0.05 or 0.01). Conclusion Novariation of [Ca^(2+) ]_i caused by EM and GM at lower concentrations might relate to theequilibrium of their promotion of mitochondrion Ca^(2+) -uptake with their inhibition of endoplasmicreticulum Ca^(2+) -uptake. The elevation of [Ca^(2+) ]_i caused by EM and GM at higherconcentrations might correlate with their inhibition of mitochondrion Ca^(2+) -uptake andendoplasmic reticulum Ca^(2+) -uptake.展开更多
Objective: To study the effects of etimicin (EM) and gentamicin (GM) on renal endoplasmic reticulum 45 Ca 2+ uptake and Ca 2+ Mg 2+ ATPase activity. Methods: Using 45 Ca 2+ inc...Objective: To study the effects of etimicin (EM) and gentamicin (GM) on renal endoplasmic reticulum 45 Ca 2+ uptake and Ca 2+ Mg 2+ ATPase activity. Methods: Using 45 Ca 2+ incorporation technique and peacock blue spectrophotometry respectively. Results: EM and GM (≥3.4×10 4 mol·L 1 ) inhibited endoplasmic reticulum 45 Ca 2+ uptake (the rate of inhibition: ≥17.4% and ≥25.5%, respectively); EM and GM (3.4×10 2 mol·L 1 ) inhibited Ca 2+ Mg 2+ ATPase activity (the rate of inhibition: 24.2% and 29.2%, respectively). Conclusion: At high concentration, EM and GM elevated intracellular calcium which may be related to their nephrotoxicity.展开更多
文摘Aim Intracellular calcium ([Ca^(2+) ]_i) is mainly regulated by mitochondriaand endo-plasmic reticula. This study was carried out to ascertain whether the elementary mechanismof the effects of etimicin (EM) and gentamicin (GM) on [Ca^(2+) ]_i is related to their effects onmitochondrion Ca^(2+) -uptake and endoplasmic reticulum Ca^(2+) -uptake. Methods The effects of GMand EM on [Ca^(2+) ]_i in LLC-PK1 were determined with a fluorescent probe of Fura-2/AM. The effectsof EM and GM on mitochondrion Ca^(2+) -uptake and endoplasmic reticulum Ca^(2+) -uptake weredetermined by isotope indicator (^(45)Ca^(2+) ) . Results EM and GM at the concentration of 1mmol·L^(-1) had no significant effect on [Ca^(2+) ]_i(P. > 0.05) and at 10 mmol·L^(-1)significantly caused [Ca^(2+) ]_i to increase (P < 0.01). EM and GM at 1 mmol·L^(-1) causedmitochondrion Ca^(2+)-uptake to ascend dramatically (P < 0.05) and at 10 mmol·L^(-1) causedmitochondrion Ca^(2+) -uptake to descend significantly. EM and GM at more than 0.34 mrnol·L^(-1)significantly inhibited endoplasmic reticulum Ca^(2+) -uptake (P < 0.05 or 0.01). Conclusion Novariation of [Ca^(2+) ]_i caused by EM and GM at lower concentrations might relate to theequilibrium of their promotion of mitochondrion Ca^(2+) -uptake with their inhibition of endoplasmicreticulum Ca^(2+) -uptake. The elevation of [Ca^(2+) ]_i caused by EM and GM at higherconcentrations might correlate with their inhibition of mitochondrion Ca^(2+) -uptake andendoplasmic reticulum Ca^(2+) -uptake.
文摘Objective: To study the effects of etimicin (EM) and gentamicin (GM) on renal endoplasmic reticulum 45 Ca 2+ uptake and Ca 2+ Mg 2+ ATPase activity. Methods: Using 45 Ca 2+ incorporation technique and peacock blue spectrophotometry respectively. Results: EM and GM (≥3.4×10 4 mol·L 1 ) inhibited endoplasmic reticulum 45 Ca 2+ uptake (the rate of inhibition: ≥17.4% and ≥25.5%, respectively); EM and GM (3.4×10 2 mol·L 1 ) inhibited Ca 2+ Mg 2+ ATPase activity (the rate of inhibition: 24.2% and 29.2%, respectively). Conclusion: At high concentration, EM and GM elevated intracellular calcium which may be related to their nephrotoxicity.
