BACKGROUND： Energy depletion, induced by ischemia or hypoxia, is one of the first events in neuronal injury. OBJECTIVE： To investigate the dynamic changes of Na^＋-K^＋-ATPase and Ca^2＋-ATPase activity in the rat b...BACKGROUND： Energy depletion, induced by ischemia or hypoxia, is one of the first events in neuronal injury. OBJECTIVE： To investigate the dynamic changes of Na^＋-K^＋-ATPase and Ca^2＋-ATPase activity in the rat brain following transient global cerebral ischemia-reperfusion （IR）, as well as the effects of hyperbaric oxygen （HBO） treatment. DESIGN, TIME AND SETTING： A randomized and controlled animal study was performed in the Department of Biochemistry and Molecular Biology, Capital Medical University between February and December 2006. MATERIALS： Clean-grade, female, Sprague Dawley rats were provided by the Animal Research Department of Capital Medical University （License number： SYXK11-00-0047）. Na^＋-K^＋-ATPase and Ca^2＋-ATPase kits were provided by Nanjing Jiancheng Bioengineering Institute （Nanjing, China）. A hyperbaric oxygen chamber （DWC150-300） was supplied by Shanghai 701 Medical Oxygen Chamber Factory （Shanghai, China）. METHODS： Sixty-three rats were randomly divided into nine groups： sham operated group （sham-O） as control, groups of IR, and groups treated with hyperbaric oxygen （HBO） after IR. Animal from the IR and HBO groups were sacrificed after four different survival intervals of 6, 24, 48 and 96 hours, respectively. Each group consisted of seven rats. The rats of HBO groups were placed into the hyperbaric chamber. The HBO chamber was flushed with pure oxygen for 5 minutes, followed by a gradual rise in pressure over 5 minutes and stabilization at 0.2 MPa. Then, pure oxygen was supplied for 45 minutes in stabilized pressure, followed by gradually reduced pressure over 15 minutes. The rats of the 6-h HBO group were placed into the HBO chamber following reperfusion for 3 hours on the first day, which was repeated on three consecutive days, always at the same time. Rats in the sham-O group and IR group remained under normal atmospheric pressure. MAIN OUTCOME MEASURES： The Na^＋-K^＋-ATPase and Ca^2＋-ATPase activity in rat brain homogenate was detected by the ammonium molybdate assay method. RESULTS： All 63 rats were included in the final analysis. Alter 6 hours, Na^＋-K^＋-ATPase activity was significantly greater in HBO animals, compared with IR animals （P 〈 0.05） and sham-O controls （P〈 0.01）. In both, the HBO group and IR group, Na^＋-K^＋-ATPase activity returned to normal levels after 24 hours （P 〉 0.05）. At 48 and 96 hours, Na^＋-K^＋-ATPase activity was significantly greater in HBO and IR animals, compared with sham-O animals （P 〈 0.05）. Ca^2＋-ATPase activity was significantly greater in the HBO group after 6 hours, compared with the sham-O group （P 〈 0.01 ）, and returned to normal levels at 24 and 96 hours （P 〉 0.05）. In the IR group, Ca^2＋-ATPase activity was significantly higher after 6 hours than in the sharn-O group （P〈 0.01）, and returned to normal levels after 24 hours （P 〉 0.05）. CONCLUSION： The Na^＋-K^＋-ATPase and Ca^2＋-ATPase activity in IR groups increased during the acute and the delayed phase following transient global cerebral IR. HBO treatment not only increased Na^＋-K^＋-ATPase activity at the acute stage, but also induced a faster recovery of Ca^2＋-ATPase activity.展开更多
This study was designed to determine if repeated hyperbaric oxygen (HBO) exposure induces ischemic tolerance in focal cerebral ischemia Methods Sixty male SD rats were used in this study Thirty animals underw...This study was designed to determine if repeated hyperbaric oxygen (HBO) exposure induces ischemic tolerance in focal cerebral ischemia Methods Sixty male SD rats were used in this study Thirty animals underwent transient middle cerebral artery occlusion (MCAO) and the other thirty permanent MCAO model The rats were randomly allocated to 3 sub-groups: control group (n=10), HBO-3 group (n=10), and HBO-5 group (n=10) The animals in HBO-3 and HBO-5 groups received 1*!hour hyperbaric oxygenation at 2 5 atmosphere absolute (ATA) in 100% oxygen every day for 3 and 5 days, respectively The animals in the control group received sham treatments 24*!hours after the last HBO, transient MCAO (120 min) and permanent MCAO were induced by introducing a 3-0 nylon monofilament suture through internal carotid artery based on the Koizumi technique The neurological outcome was evaluated until 24*!hours after reperfusion in transient MCAO rats and ischemia in permanent MCAO rats The infarct volume was then assessed by TTC staining Results In transient MCAO rats, the neurological outcome in both the HBO-3 and HBO-5 groups was better than that of the control group ( P <0 05 and 0 001) The infarct volume decreased from 171 5±113*!mm 3 to 40 6±49 9*!mm 3 ( P <0 05) in the HBO-3 group and 16 2±28 8*!mm 3 ( P <0 01) in the HBO-5 group There were no significant differences in neurological outcome and infarct volume among the three groups in permanent MCAO rats Conclusions The present study demonstrated that HBO preconditioning can induce ischemic tolerance in transient not permanent MCAO rats in a “dose-dependent' manner展开更多
基金Science and Technology Development Program of Beijing Education Committee, No.KM200510025004
文摘BACKGROUND： Energy depletion, induced by ischemia or hypoxia, is one of the first events in neuronal injury. OBJECTIVE： To investigate the dynamic changes of Na^＋-K^＋-ATPase and Ca^2＋-ATPase activity in the rat brain following transient global cerebral ischemia-reperfusion （IR）, as well as the effects of hyperbaric oxygen （HBO） treatment. DESIGN, TIME AND SETTING： A randomized and controlled animal study was performed in the Department of Biochemistry and Molecular Biology, Capital Medical University between February and December 2006. MATERIALS： Clean-grade, female, Sprague Dawley rats were provided by the Animal Research Department of Capital Medical University （License number： SYXK11-00-0047）. Na^＋-K^＋-ATPase and Ca^2＋-ATPase kits were provided by Nanjing Jiancheng Bioengineering Institute （Nanjing, China）. A hyperbaric oxygen chamber （DWC150-300） was supplied by Shanghai 701 Medical Oxygen Chamber Factory （Shanghai, China）. METHODS： Sixty-three rats were randomly divided into nine groups： sham operated group （sham-O） as control, groups of IR, and groups treated with hyperbaric oxygen （HBO） after IR. Animal from the IR and HBO groups were sacrificed after four different survival intervals of 6, 24, 48 and 96 hours, respectively. Each group consisted of seven rats. The rats of HBO groups were placed into the hyperbaric chamber. The HBO chamber was flushed with pure oxygen for 5 minutes, followed by a gradual rise in pressure over 5 minutes and stabilization at 0.2 MPa. Then, pure oxygen was supplied for 45 minutes in stabilized pressure, followed by gradually reduced pressure over 15 minutes. The rats of the 6-h HBO group were placed into the HBO chamber following reperfusion for 3 hours on the first day, which was repeated on three consecutive days, always at the same time. Rats in the sham-O group and IR group remained under normal atmospheric pressure. MAIN OUTCOME MEASURES： The Na^＋-K^＋-ATPase and Ca^2＋-ATPase activity in rat brain homogenate was detected by the ammonium molybdate assay method. RESULTS： All 63 rats were included in the final analysis. Alter 6 hours, Na^＋-K^＋-ATPase activity was significantly greater in HBO animals, compared with IR animals （P 〈 0.05） and sham-O controls （P〈 0.01）. In both, the HBO group and IR group, Na^＋-K^＋-ATPase activity returned to normal levels after 24 hours （P 〉 0.05）. At 48 and 96 hours, Na^＋-K^＋-ATPase activity was significantly greater in HBO and IR animals, compared with sham-O animals （P 〈 0.05）. Ca^2＋-ATPase activity was significantly greater in the HBO group after 6 hours, compared with the sham-O group （P 〈 0.01 ）, and returned to normal levels at 24 and 96 hours （P 〉 0.05）. In the IR group, Ca^2＋-ATPase activity was significantly higher after 6 hours than in the sharn-O group （P〈 0.01）, and returned to normal levels after 24 hours （P 〉 0.05）. CONCLUSION： The Na^＋-K^＋-ATPase and Ca^2＋-ATPase activity in IR groups increased during the acute and the delayed phase following transient global cerebral IR. HBO treatment not only increased Na^＋-K^＋-ATPase activity at the acute stage, but also induced a faster recovery of Ca^2＋-ATPase activity.
基金ThisstudywassupportedinpartbyagrantfromtheNationalNaturalScienceFoundationofChina (No 396 70 6 99)
文摘This study was designed to determine if repeated hyperbaric oxygen (HBO) exposure induces ischemic tolerance in focal cerebral ischemia Methods Sixty male SD rats were used in this study Thirty animals underwent transient middle cerebral artery occlusion (MCAO) and the other thirty permanent MCAO model The rats were randomly allocated to 3 sub-groups: control group (n=10), HBO-3 group (n=10), and HBO-5 group (n=10) The animals in HBO-3 and HBO-5 groups received 1*!hour hyperbaric oxygenation at 2 5 atmosphere absolute (ATA) in 100% oxygen every day for 3 and 5 days, respectively The animals in the control group received sham treatments 24*!hours after the last HBO, transient MCAO (120 min) and permanent MCAO were induced by introducing a 3-0 nylon monofilament suture through internal carotid artery based on the Koizumi technique The neurological outcome was evaluated until 24*!hours after reperfusion in transient MCAO rats and ischemia in permanent MCAO rats The infarct volume was then assessed by TTC staining Results In transient MCAO rats, the neurological outcome in both the HBO-3 and HBO-5 groups was better than that of the control group ( P <0 05 and 0 001) The infarct volume decreased from 171 5±113*!mm 3 to 40 6±49 9*!mm 3 ( P <0 05) in the HBO-3 group and 16 2±28 8*!mm 3 ( P <0 01) in the HBO-5 group There were no significant differences in neurological outcome and infarct volume among the three groups in permanent MCAO rats Conclusions The present study demonstrated that HBO preconditioning can induce ischemic tolerance in transient not permanent MCAO rats in a “dose-dependent' manner
