RESUMO
Objective To investigate effects of ischemic postconditioning on the nitric oxide ( NO) and nitric oxide synthase ( NOS) in diabetic rat brain tissues .Methods Thirty Wistar rats were diabetic models induced by intraperitoneal injuction of stepto-zotocin (STZ), and randomly divided into three groups: Control group (normal, diabetic), cerebral ischemia group, and ischemic postconditioning ( I-POST) group.The rats of cerebral ischemia group and ischemic postconditioning group were made model of cere -bral ischemia by ligation carotid artery .Hematoxylin-eosin ( HE) was used to observe their pathological changes in control and diabetic groups.Enzyme-linked immunosorbent assay ( ELISA) method was used to detect the expression and changes of NO and NOS in the sera in each group .Western Blot method was used to investigate the expression and changes of NOS in the retinal tissues in each group .Results For I-POST group , brain tissue defects were decreased , neuronal cells were increased , serum inducible NOS ( iNOS) content was significantly lower than endothelial NOS (eNOS) and neuronal NOS (nNOS) ( P 0.05 ) .Conclusions Is-chemic postconditioning can protect the brain tissue of diabetic rats by inhibiting NOS activity especially iNOS .