AIM: To investigate whether pretreatment with 3-n-butylphthalide (NBP) ameliorates blood brain barrier (BBB) dysfunction in a rat model of focal cerebral ischemia-reperfusion injury (CIRI). METHODS: Male SD rats (n=120, 24 rats in each group) were randomly divided into sham operation group (sham group), model group (IR group), low dose group of NBP pretreatment (NBP I group), medium dose group of NBP pretreatment (NBP II group) and high dose group of NBP pretreatment (NBP III group). The model of CIRI was established by a suture method. After ischemia for 2 h and reperfusion for 24 h, the contents of water and Evans blue (EB) were detected. The pathological changes of the BBB ultrastructure were observed under transmission electron microscope. The protein level of matrix metalloproteinases 9 (MMP-9) was measured by immunohistochemical technique. The mRNA expression of MMP-9 was determined by real-time PCR. RESULTS: After CIRI, the content of water and EB was progressively increased, the BBB was damaged seriously, and the expression of MMP-9 was significantly up-regulated compared with sham group (all P<0.01). Pretreatment with NBP significantly decreased the contents of water and EB, relieved morphological damage of the BBB, and reduced the expression of MMP-9 obviously (all P<0.01). Compared with NBP I group, the changes in NBP II and III group were remarkable (P<0.05), but the difference between NBP II group and NBP III group was not obvious (P>0.05). CONCLUSION: Pretreatment of 3-n-butylphthalide has preventive effect against cerebral ischemia reperfusion injury in the rats, which may be related to decrease the expression of MMP-9 and reduce the permeability of blood brain barrier. 相似文献
BackgroundThe blood‐brain barrier (BBB), which separates the intravascular and neuropil compartments, characterizes the vascular bed of the brain and is essential for its proper function. Recent advances in imaging techniques have driven the development of methods for quantitative assessment of BBB permeability.Hypothesis/ObjectivesPermeability of the BBB can be assessed quantitatively in dogs with meningoencephalitis of unknown origin (MUO) and its status is associated with the occurrence of seizures.AnimalsForty dogs with MUO and 12 dogs without MUO.MethodsRetrospective, prospective cohort study. Both dynamic contrast enhancement (DCE) and subtraction enhancement analysis (SEA) methods were used to evaluate of BBB permeability in affected (DCE, n = 8; SEA, n = 32) and control dogs (DCE, n = 6; SEA, n = 6). Association between BBB dysfunction (BBBD) score and clinical characteristics was examined. In brain regions where BBBD was identified by DCE or SEA magnetic resonance imaging (MRI) analysis, immunofluorescent staining for albumin, glial fibrillary acidic protein, ionized calcium binding adaptor molecule, and phosphorylated mothers against decapentaplegic homolog 2 were performed to detect albumin extravasation, reactive astrocytes, activated microglia, and transforming growth factor beta signaling, respectively.ResultsDogs with BBBD had significantly higher seizure prevalence (72% vs 19%; P = .01) when compared to MUO dogs with no BBBD. The addition of SEA to routine MRI evaluation increased the identification rate of brain pathology in dogs with MUO from 50% to 72%.Conclusions and Clinical ImportanceImaging‐based assessment of BBB integrity has the potential to predict risk of seizures in dogs with MUO. 相似文献
AIM: To study the effect of moderate hypothermia on immature rats with hypoxic-ischimic brain damage (HIBD). METHODS: The rats with HIBD were divided into normothermic recovered group (IN) and moderate-hypothermic recovered group (IH). Sham-operated rat pups were normothermic control group (NC) and moderate-hypothermic control group (HC). 0, 2, 6, 24, 48, 72 h after the end of hypoxic-ischemic (HI) insult, the brain was homogenized for measuring glucose and ATP, brain mitochondria was extracted for SDH activity, complex II activity and the capacity of ATP synthesization. RESULTS: In IN group, the brain glucose was significantly lower at 0 h, and recovered as normal at 2 h. The brain ATP and brain-mitochondrial SDH activities were firstly decreased at 2 h, 6 h and then recovered gradually, it was at it's peak value at 72 h. Brain-mitochondrial complex II activity and the capacity of ATP synthesis were recovered at 2 h, but they decreased again at 6 h and came to normal level at 72 h. In moderate-hypothermic group, all the indexes were significantly higher at all the time point than that in IN groups. CONCLUSION: Moderate hypothermia inhibits the decrease in the mitochondrial SDH activity, mitochondrial complex II activity and the capacity of ATP synthesis, increases the brain ATP concentration, improves the energy metabolism, and then protects the brain tissue. 相似文献
1. Acrylamide (ACR) is a potent neurotoxicant, although information on its toxic influence on the developing neural system is still limited. The effects of in-ovo-injected ACR on the antioxidant system activity in the brain of newly hatched chickens was examined. This model eliminated the mother’s contribution to embryonic development. It was also recognised as an adequate model for animal embryonic development.
2. ACR was injected on d 4 of embryogenesis – in doses of 1.25 and 2.50 mg/egg (n = 40 eggs/group/120 eggs). The doses corresponded well with ACR doses used in other animal studies and their concentrations in certain animal feeds.
3. Mortality and incidences of malformations were not found to increase significantly. Significant depletion of glutathione was detected in the cerebellum, cerebrum and medulla oblongata of specimens exposed to the highest doses of ACR. Enzymatic activity was affected by the highest ACR doses. Glutathione peroxidase (GPx) activity increased significantly in the cerebrum, medulla oblongata and the hypothalamus. Superoxide dismutase (SOD) activity increased significantly in hypothalamus and decreased in cerebellum and cerebrum. A significant depletion of catalase (CAT) activity was detected in cerebellum. In the hypothalamus, the increased SOD/GPx and SOD/CAT ratios suggest the risk of H2O2.
4. It was concluded that ACR significantly influences the antioxidative defence in the chicken brain at doses of 1.25 and 2.50 mg/egg. 相似文献