ABSTRACT
Objective To investigate the anti-oxidant effect and the possible mechanisms ofpicrodide II in cerebral ischemia/reperfusion injuries in rats. Methods A total of 90 adult, healthy, mmale Wistar rats were used to established the middle cerebral artery occlusion reperfusion (MCAO/R) models by intraluminal monofilament suture on the left external-internal carotid artery. The treatment group and the positive control group were respectively injected with 1.0％ picroside II (10 mg/kg, 250 μl) and salvianic acid A sodium (10 mg/kg, 250 μl) via the tail vein, and the negative control group and sham-surgery group were injected with 0.1mol/L phosphate buffer saline (PBS) 250 μl. The neurological deficit scores were evaluated with Bederson's test. The cerebral infarction volume was observed with tetrazolium (TTC) staining. The apoptosis positive cells were counted by terminal deoxynucleotidyl transferase dUTP nick-end labeling and the expressions of inducible nitric oxide synthase (iNOS) and superoxide dismutase (SOD) were detected with immunohistochemical assay.The concentration of iNOS and SOD proteins in brain tissue was detected by enzyme linked immunosorbent assay.Results Neurological behavioral malfunction appeared in all the rats with MCAO/R. The infarction focuses emerged in the ischemic hemisphere following the MCAO/R injuries. The number of apoptotic cells and the expression of iNOS increased while the SOD reduced after MCAO/R. After the treatment of picrodide Ⅱ, the nervous behavioral function (1.28±0.38)improved, the infarction volume(68.73±4.46)％ reduced, the number of apoptosis positive cells(6.10± 1.26), the expressions and the concentrations in brain tissue of iNOS(4.67+0.51)decressed while those of SOD (0.53 ±0.14) increased significantly compared with the negative control groups(t=3.16、 2.51、 4.15、3.12、 3.25, P＜0.05). Conclusion PicrodideⅡ might play a neuroprotective effect by inhibiting the neuronal apoptosis and the expressions of iNOS and SOD after cerebral ischemia/reperfusion injuries.