Effect of 1,5-isoquinolinediol on retinal poly(ADP-ribose) polymerase (PARP) expression in diabetes. (a) Cryosections from normal (N) and diabetic (D) retina were subjected to immunostaining using anti-PARP antibodies (green) and DAPI (blue) was used to stain the nuclei. The sections were imaged at 20x magnification using Olympus BX-UCB fluorescent microscope. RGC: retinal ganglion cell; IPL: inner plexiform layer; INL: inner nuclear layer; ONL: outer nuclear layer. (b) Representative Western blot analyses of retinal poly(ADP-ribosyl)ated proteins in control and diabetic rats maintained with and without PARP inhibitor treatment. (c) PARP activation was measured by western blot technique, and the ratio of active PARP-2 (85 KDa) and pro-PARP-1 (120 kDa) was calculated in control and diabetic rats maintained with and without PARP inhibitor treatment. Measurements were made in duplicate in six to eight rats in each group. Western blots are representative of three different experiments. Results are expressed as mean ± SD. Values obtained from nondiabetic rats are considered as 100%. N: nondiabetic rat; D: diabetic rat; D + IQ: diabetic rat treated with 1,5-isoquinolinediol. compared with nondiabetic rat. compared with diabetic rat.
