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Objective To investigate the effect of recombinant human erythropoietin(rh‐EPO ) on acute cerebral injury and expression of GLT‐1 and GLAST in rat .Methods Sixty SD rats were randomly divided into three groups by weight :control group (n=18) ,acute cerebral injury group(n=22) and rh‐EPO conditioning group(n=20) .Acute cerebral injury models were made by modified Feeney′s method .rh‐EPO was injected in abdominal cavity 15 min after acute cerebral injury in rh‐EPO conditioning group .Rats′brain were removed 48 h after experiments .Rat GLT‐1 and GLAST mRNA expression were determined by RT‐PCR , GLT‐1 and GLAST protein expression were determined by Western blot .Results GLT‐1/GLAST mRNA and protein expression decreased significantly after acute cerebral injury(all P<0 .01) ,but increased significantly in rh‐EPO preconditioning group com‐pared with acute cerebral injury group(all P<0 .01) .Conclusion rh‐EPO preconditioning may protect against acute cerebral injury by up regulating the expression of GLT‐1/GLAST .
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AIM: To observe the effects of hypoxia on the levels of nitric oxide (NO), endothelin (ET-1) and the expression of inducible nitric oxide synthase (iNOS) mRNA in human umbilical vein endothelial cells (HUVECs), and further investigate the mechanism of hypoxic pulmonary hypertension. METHODS: On the basis of the HUVECs culture model, the methods of nitrate reductase and radioimmunoassay were used to determine the changes of NO and ET-1 in the medium secreted by HUVECs, and the expression of iNOS mRNA was analyzed by semi quantitative RT-PCR after exposure to hypoxia (3% O_2) for 6, 12 or 24 h. RESULTS: The contents of NO_2-/NO_3-and ET-1 in hypoxia group in the medium was significantly higher than that in control group at different time points (P
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0 05) 97% Spectral edge frequency (SEF) and median power frequency(MPF) decreased after intravenous clonidine(P0 05) Conclusions The contents of NE and E in cortex can indicate the inhabitive degree of isoflurane on consciousness, and the change of MAC of isoflurane is independent of the changes of NE and E contents in cortex,suggesting that the region where to determine the MAC of isoflurane is not at cortex
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Objective To investigate the effects of inhalation of different concentrations of isoflurane on global and regional cerebral glucose metabolic rate (CMRglu) in healthy volunteers using positron emission tomography (PET) scan.Methods The study was approved by the ethic committee of the hospital. After obtaining written informed consent we studied eight right-handed healthy volunteers (3 male, 5 female), aged 21-28 yrs. Each volunteer underwent 3 PET scans.They were fasted for 8 h prior to study. The PET scan was performed when conscious, at 0.5 and 1.0 MAC isoflurane anesthesia. The interval between two PET scans was 1 week. Scans were obtained with a MASEP CPET Plus scanner (2.0 mm resolution-FWHM) using the 18 fluorodeoxyglucose technique. Results The whole brain CMRglu averaged 30.0?1.1 ?mol?100 mg-1?min-1 when the volunteer was awake. Isoflurane anesthesia significantly reduced whole-brain CMRglu by 24% to 23.3?1.4 ?mol?100 mg-1?min-1 at 0.5 MAC and by 41% to 18.4?0.9 ?mol?100mg-1?min-1 at 1.0 MAC (P
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Objective To study the changes in cerebral cortex glutamate (G) content induced by isoflurane inhalation alone or combined with 2-amino-5-phosphonovalerate (AP5),a NMDA receptor competitive antagonist.Methods Six adult male SD rats were anesthetized with isoflurane. Dialysis probe (internal diameter=0.05mm) which was connected to a micro-infusion pump filled with artifical cerebrospinal fluid(ACSF) was inserted into cerebral cortex. The dialysate was collected for determination of G concentration. After the baseline MAC for isoflurane was measured, the study was carried out in 4 groups based on the concentration of isoflurane inhalation: group Ⅰ:1%; group Ⅱ:1MAC; group Ⅲ:2% and group Ⅳ: the effect of AP5 on isoflurane MAC value. In group Ⅳ AP5 was continuously infused at a rate of 100 ?g?kg -1?h -1 via the vein in the tail and the MAC for isoflurane was measured again. G concentration of dialysate was measured and EEG and SEP were monitored in every group.Results G concentration of cerebral cortex dialysate was decreasing with increasing concentration of isoflurane from group Ⅰ to group Ⅲ. Concentration of isoflurane was negatively correlated with cerebral G content (r=-0.839,P