| Part 1. HBO on brain edema induced by experimental intracerebral hemorrhagePurpose:To investigate the effect of HBO treatment on brain edema induced by experimental intracerebral hemorrhage and intracaudate infusion of thrombin and iron.Methods:Totally 60 male SD rats (weight:300-350g) spplied by the animal experimental center of Fudan University were adopted in our experiment. HBO treated animals were pressurized over 15 minutes to a plateau of 3 ATA with 100% O2 supplied continuously and maintained for 60 minutes. Decompression was then carried over 25～30 mintutes. Control animals were also transferred into the HBO chamber but received normbaric room air for the the same time as HBO treated rats.This study had three groups.Group 1:12 rats received an infusion of 100μl autologous blood into the caudate,1 h after infusion, rats underwent HBO treatment or sham treatment once, and were sacrificed 24 h later for brain edema measurements. (6 rats in the HBO group and control group, respectively). Another 12 rats received an infusion of 100 u 1 autologous blood into the caudate,1h after infusion, rats underwent HBO treatment or sham treatment once,24 h and 48 h later rat underwent HBO treatment or sham treatment once respectively, rats were sacrificed 72 h later for brain edema measurements. (6 rats in the HBO group and control group, respectively)Group 2:12 rats received an infusion of rat thrombin (5U/50ul saline) into the caudate,1 h after infusion, rats underwent HBO treatment or sham treatment once, and were sacrificed 24 h later for brain edema measurements. (6 rats in the HBO group and control group, respectively) Another 12 rats received an infusion of Fecl2 (1 mM,50ul) into the caudate,1 h after infusion, rats underwent HBO treatment or sham treatment once, and were sacrificed 24 h later for brain edema measurements. (6 rats in the HBO group and control group, respectively)Group 3:6 rats received an infusion of 100μl autologous blood into the caudate,1 h after infusion, rats underwent HBO treatment or sham treatment once, and were sacrificed 24 h later for Western blot analysis of HO-1. (6 rats in the HBO group and control group, respectively). Another 6 rats received an infusion of 100μl autologous blood into the caudate,1 h after infusion, rats underwent HBO treatment or sham treatment once, and were sacrificed 24 h later for immunohistochemical analysis of HO-1.Brain water content and relative density of band data were analyzed using Stata7.0 software, and statistical analysis was carried out by two-tailed student t test.Results:1. Relative to control group, sigle HBO treatment significantly attenuated brain edema after ICH (80.1±1.3% vs 81.4±1.1%, P<0.05)2. Relative to control group, single HBO treatment neighter significantly attenuated nor significantly aggravated brain edema after intracaudate infusion of thrombin (81.8±0.7% vs 82.6±0.8%, P>0.05).3. Relative to control group, sigle HBO treatment significantly aggravated ipisilateral cortex and basal ganglion tissue edema after intracaudate infusion of iron (84.9±0.9% and 82.8±1.0% vs 82.1±1.9% and 81.2±0.7%, P<0.05)。4. Western blot analysis and immunohistochemical analysis show less HO-1 immunoactivity in HBO group.5. Repeated HBO treatments after ICH neigher significantly aggravated nor significantly attenuated brain edema 72 h after ICH. (81.8±0.7% vs 2.6±0.8% P>0.05). Conclusions:1. Single HBO trearment after ICH significantly attenuates brain edema 24 h later after ICH. It has no effect on brain edema induced by thrombin; however, it significantly aggravates the brain edema inducd by the iron, and down regulates the HO-1 level in basal ganglion tissue.2. Repeated HBO treatment after ICH has no effect on brain edema induced by ICH. Acute intracerebral hemorrhage is not appropriate for HBO therapy.Part 2. HBOP on brain edema induced by experimental intracerebral hemorrhagePurpose:To investigate the effect of HBOP on brain edema induced by experimental intracerebral hemorrhage.Methods:Totally 78 male SD rats (weight:300-350g) spplied by the animal experimental center of Fudan University were adopted in our experiment. HBO treated animals were pressurized oer 1v5 minutes to a plateau of 3 ATA with 100% O2 supplied continuously and maintained for 60 minutes. Decompression was then carried over 25～30 mintutes. Control animals were also transferred into the HBO chamber but received normbaric room air for the the same time as HBO treated rats. This study had four groups.Group 1:36 rats received 2 or 3 or 5 consecutive sessions of HBOP or sham preconditioning,24 h after the final preconditioning, rats received an infusion of 100μl autologous blood into the caudate. Rats were sacrificed 24 h after infusion for brain edema measurements (36rats; 6 rats in the HBOP2d,HBOP3d,HBOP5d groups and control2d,control3d and control5d groups, respectively). Another 12 rat underwent 5 consecutive sessions of HBOP or sham preconditioning; 24 h after the final preconditioning, rats received an infusion of 100 u 1 autologous blood into the caudate. Rats were sacrificed 72 h after infusion for brain edema measurements (6 rats in HBOP group and control group respectively).Group 2:6 rats received 5 consecutive sessions of HBOP or sham preconditioning,24 h after the final preconditioning, rats were sacrificed for Western blot analysis of P44/42 MAPK,p70 S6K,HO-1 (3 rats in HBOP group and control group respectively).Another 6 rats received 5 consecutive sessions of HBOP or sham preconditioning,24 h after the final preconditioning, rats were sacrificed for immunohistochemical analysis of P44/42 MAPK,p70 S6K,HO-1(3 rats in HBOP group and control group respectively).Group 3:12 rats received intracaudate injection of 5 nmol PD098059(an inhibitor of P44/42 MAPK) or 50μl 4%DMSO(an vehicle of PD098059 solution) before the first of five sessions of HBOP,24 h after the final preconditioning, rats received an infusion of 100μl autologous blood into the caudate. Rats were sacrificed 24 h after ICH for brain edema measurements (6 rats in PD098059 group and control group respectively).Group 4:6 rats received 5 consecutive sessions of HBOP or sham preconditioning,24 h after the final preconditioning, rats received an infusion of 100 u l autologous blood into the caudate. Rats were sacrificed 72 hours after infusion. The histopathological appearance around the hematoma was observed microscopically and neuronal cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) (6rats; 3 in the HBOP group and control group, respectively).Results:1. Two and three sessions consecutive sessions of HBOP did not significantly attenuate brain edema after ICH (81.0±1.2% and 80.6±1.2% vs 81.3±1.1% and 81.2±0.2%,P>0.05) 2. Five sessions consecutive sessions of HBOP significantly attenuated brain edema 24 h and 72 h later after ICH (79.5±0.9% and 81.6±0.7% vs 81.2±1.2% and 82.8±0.9%, P<0.05)3. Western blot analysis and immunohistochemical analysis show strong P44/42 MAPK,p70 S6K,HO-1 immunoactivity in HBO group.4. Intracaudate infusion of PD098059 abolished HBOP induced protection against ICH induced brain edema formation(80.8±1.1% vs 79.6±0.5%, P<0.05)5. Relative to the control group, Inflammatory cell infiltration and neuronal cell apoptosis were also significantly decreased in the HBOP group.Conclusions:1. Preconditioning with HBO protects against brain edema formation following ICH. Activation of the P44/42 MAPK pathway contribute to that protection.2. Activation of p70 S6 K may have a role in heat shock protein synthesis after HBOP and may contribute to HBOP-induced brain protection.3. HBOP inhibits the inflammatory reaction and neuronal cell apoptosis following experimental intracerebral hemorrhage in rats, which may also contribute to HBOP-induced brain protection.
|
PDF Full Text Request