爱大霉素和庆大霉素对胞浆Ca^(2+)影响的初步机制

Preliminary Study on the Mechanism of the Effects of Etimicin and Gentamicin on Cellular Calcium

目的 :探讨爱大霉素 (EM )和庆大霉素 (GM )对胞浆Ca2 +影响的初步机制。方法 :以Fura -2/AM为探针测定EM和GM在不同浓度时对LLC -PK1肾上皮细胞胞浆Ca2 +的影响 ,同位素示踪法测定EM和GM对线粒体Ca2 +摄取和内质网Ca2 +摄取的影响。结果 :EM和GM在1mmol/L时对胞浆Ca2 +浓度无显著影响 (P>0 05) ;在10mmol/L时可使胞浆Ca2 +显著上升 (P<0 01)。EM和GM在1mmol/L时显著促进线粒体Ca2 +摄取 (P<0 05) ;在10mmol/L时 ,二者显著抑制线粒体Ca2 +摄取。EM和GM在>3 4×10-1mmol/L时显著抑制内质网Ca2 +摄取 (P<0 05或P<0 01)。结论 :低浓度EM和GM未能引起胞浆Ca2 +升高 ,可能与其促进线粒体Ca2 +摄取与抑制内质网Ca2 +摄取相互平衡有关 ;高浓度EM和GM引起胞浆Ca2 +升高 ,可能与其均抑制线粒体和内质网Ca2

OBJECTIVE:To tentatively study the mechanism of the effects of etimicin(EM)and gentamicin(GM)on celˉlular calcium([Ca 2+ ]i).METHODS:The effects of GM and EM on cellular calcium of LLC-PK1were determined by a fluoˉrescent probe of Fura-2/AM.The effects of EM and GM on mitochondria and endoplasmic Ca 2+ -uptake were detected by isotope indicator.RESULTS:EM and GM at the concentration of1mmol/L had no significant effect on[Ca 2+ ]i,P>0.05.They at10mmol/L significantly increased [Ca 2+ ]i,P<0.01.EM and GM1mmol/L caused mitochondria Ca 2+ -uptake to ascend dramatically,P<0.05.They at10mmol/L caused mitochondria Ca 2+ -uptake to descend significantly.EM and GM>3.4×10 -1 mmol/L significantly inhibited endoplasmic Ca 2+ -uptake,P<0.05or0.01.CONCLUSION:That EM and GM at lower conˉcentrations cause no[Ca 2+ ]i elevation may correlate with the equilibrium of their promotion of mitochondria Ca 2+ -uptake and their inhibition of endoplasmic Ca 2+ -uptake.That EM and GM at higher concentration cause [Ca 2+ ]i elevation may correlate with their inhibition of mitochondria Ca 2+ -uptake and endoplasmic Ca 2+ -uptake.