Effects of NOS on the action of CHR21. (A) Endothelial nitrioxide synthase (eNOS) mediates the action of CHR21 on MTT activity in RGC-5 cells. Cells pre-exposed to 7-nitroindazole (7-NI, 50 μM, 30 min), an specific inhibitor for neuronal nitric oxide synthase (nNOS), N(5)-(-iminoethyl)-l-ornithine (l-NIO, 100 μM, 30 min), an inhibitor of endothelial NOS (eNOS), and compound 1400-W (20 μM, 30 min), a potent inhibitor of inducible NOS (iNOS), respectively, were treated with CHR20/CHR21. The MTT activity of cells determined by MTT assay. Only l-NIO attenuated the protective effects of CHR20/21 on RGC-5 cells with statistically significant; while 7-NIO and 1400 W had no statistically significant effect. &&
p < 0.01 vs. control; ##
p < 0.01 vs. SNP group; *
p < 0.05 vs.
CHR20 + SNP or CHR21 + SNP (n = 3); (B) Effects of 7-NI, l-NIO and 1400 W on the NOS activities in RGC-5 cells. RGC-5 cells were treated with 7-NI, l-NIO and 1400 W, respectively. By applying Typed NOS Detection Kit, determination of the activities of nNOS, eNOS (endothelial NOS) and iNOS was carried out. One nmol of NO formed per mL cell lysate in one minute was defined as U/mL. With *
p < 0.05 vs. control group, the difference is considered statistically significant. All values are expressed as mean ± SD (n = 3).