Reverse mode of Na+/Ca2+ exchange inhibitor, KB-r7943 attenuates tubular epithelial cell apoptosis inducde by contrast media

Objective To investigate the renoprotective effects of KB-R7943 on renal injury induced bycontrast media. Method Tubular epithelial cells were trested with varions cencentration of KB-B7943 (10-5,10-6 mol/L) for 12 hours before contrast media was used. After cells we, re incubated with contrast media (CM)(110 mgI/L) for 1 hour, cells injury was assessed by using LDH, and cell morphologic changes and cells apopto-sis were evaluated with inverted microscope and flow cytometry, respoelively. Intracellular Ca2+ and reactive oxy-gen species (ROS) were analyzed by using confocal microscope. The expression of Na+/Ca2+exchanger mRNAwas evaluated by RT-PCR. Mannitol with same osmolarity (20% mannitol, 770 mOsm/L) of CM was used as con-trol. One-way analysis of variance and q-test were used for comparison between groups. The simple linear correla-tion was employed to analyze the correlation. P < 0.05 was considered significant. Results Contrast media sig-nificantly induced tubular cells damage significantly and apoptosis at 1 hour after incubation, meanwhile, intracel-lular Ca2+ and ROS were inoreased progressively in CM group. KB-R7943 significantly attenuated cells damage andapoptosis in dose-dependent in association with decreased intracellular Ca2+ and ROS. Expression of Na+/Ca2+exchanger mRNA was not changed. Conclusions KB-R7943 has renoprotective effects on the contrast-media-in-duced renal tubular cyotoxicity Key words: Contrast Media;  Cell Apoptosis;  Na+/Ca2+ exchanger inhibitor