ABSTRACT
Objective To investigate the protection of agmatine on blood brain barrier (BBB) permeability and the effect on the expression of aquaporin 4 (AQP4) and matrix metalloproteinase 9 (MMP9) in ischemic reperfusion injury rats.Methods Sixty healthy male Sprague-Dawley rats were randomly divided into normal control group (NC),model group and agmatine group,and there were 20 rats in each group.Normal control group was treated with intraperitoneal injection of saline in 2 hours after incision and suture of skin.Model group was treated with intraperitoneal injection of saline in 2 hours after the establishment of middle cerebral artery occulation (MCAO) model.Agmatine group was treated with intraperitoneal injection of agmatine (AGM) in 2 hours after the establishment of MCAO model.The damage of blood brain barrier was detected by measuring the permeability of blood brain barrier.The infarct size of brain was observed with TTC staining.The morphological changes of neurons were observed with electron microscope.The expressions of AQP4 and MMP9 were detected using immunohistochemical method.Results The permeability of BBB of agmatine treatment group (0.31±0.10) decreased significantly compared with the model group (0.46±0.09) (P＜0.05),but was still significantly higher than the normal control group (0.24±0.12) (P＜0.05).There was no infarction area in normal control group and the infarction areas of agmatine group decreased obviously compared with the model group.Compared with model group,the number of neurons with morphological changes reduced significantly and the degree of pathological changes of neurons was obviously improved in agmatine group.Compared with normal control group,the expression of AQP4 and MMP9 in ischemic penumbra of left cerebral hemisphere parietal cortex in the rats of model group and agmatine group increased significantly(P＜0.05).And the expression of AQP4 and MMP9 in model group was significantly higher than that of agmatine group(P＜0.05).Conclusion Agmatine has a protective effect on BBB with ischemia-reperfusion injury due to its down-regulation the expression of AQP-4 and MMP-9.
ABSTRACT
Objective To investigate the effect of taurine on iron bioavailability in rats and its possible mechanism. Method SD rats were randomly divided into three groups:normal group (NG),taurine treated group (TG),experimental control group (EG). TG and EG were induced to be anemic experimentally for 4w before the study. Then the rats were fed iron supplements for 25 d,meanwhile TG was treated with taurine following hemoglobin(Hb) repletion bioassay. Regression analysis of TG and AG were measured following Hb repletion bioassay using iron supplements. And the relative biological value of TG following Hb repletion were calculated. The serum iron,unsaturated iron-binding capacity(UIBC),total iron-binding capacity(TIBC),transferin saturation(TS)and the expression of hepcidin were detected. Results The iron bioavailability of TG was higher than EG,and the RBV of TG was 126%. Other hematological variables of TG were close to NG,and better than EG. The expression of hepcidin was increased compared with NG,but decreased compared with EG. Conclusion Taurine can improve iron bioavailability in rats via suppressing hepcidin expression in rats.