Fig 1: PPO improves cell morphology, reduces ROS levels and attenuates the expression of NSE and NF-?B in a cardiopulmonary resuscitation rat model. (A) Hematoxylin and eosin staining of brain tissue from rats in the (A-a) sham, (A-b) NS, (A-c) Gly, (A-d) PPO-L, (A-e) PPO-M and (A-f) PPO-H groups. A large number of cerebral cortex cells with normal morphology were observed in the sham group (indicated by black arrows). However, numerous abnormal cerebral cortex cells exhibiting nuclear pyknosis, intense staining, vacuolation, swelling and necrosis (indicated by red triangles) were visible in the NS and Gly groups. Cell morphology was ameliorated in the PPO groups. Magnification, x400. (B) Antioxidant activity of PPO determined by an ROS assay. Representative western blots of NSE (C) and (D) quantified results. (E) Representative western blots of NF-?B and (F-I) quantified results. Band intensities were quantified using densitometric software. The band intensities of (F) NF-?Bp105, (G) NF-?Bp50 and (H) NF-?Bp-p105 were normalized to that of GAPDH, and (I) the NF-?Bp-p105/NF-?Bp105 ratio was calculated. Data are presented as the mean ± SEM of two independent experiments (n=3). *P<0.05, **P<0.01 and ***P<0.001 vs. the sham group; #P<0.05 and ##P<0.01 vs. the NS group; &P<0.05 and &&P<0.01 vs. the Gly group; @@P<0.01 vs. the PPO-L group (n=5). PPO, pomelo peel oil; ROS, reactive oxygen species; NSE, neuroenolase; NS, physiological saline; Gly, glycerin; PPO-L, 10 mg/kg PPO; PPO-M, 20 mg/kg PPO; PPO-H, 40 mg/kg PPO; NF-?Bp-p105, phosphorylated NF-?Bp105.