AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated withendothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO).METHODS: Wistar rats were randomi...AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated withendothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO).METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-α levels, liver tissuemalondialdehyde (MDA) content, and severity of hepatic I/R injury.RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7±11.0 μmol/L vs 45.3±10.1μmol/L, P<0.01). Although serum NO levels decreased significantly after hepatic I/R (P<0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8±8.6 μmol/L vs 23.8±4.7 μmol/L, P<0.01). Serum ALT and TNF-α levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5±46.4 U/L, 0.99±0.11 μg/L and 0.57±0.10 μmol/g vs668.7±78.7 U/L, 1.71±0.18 μg/Land 0.86±0.11 μmol/g, respectively, P<0.01). I/R induced significant injury to the liver both in M and F groups (P<0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P<0.05 and P<0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P<0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-β- estradiol (E2) (M+E2 group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-α levels, and liver tissue MDA content after I/R (P<0.01).The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E2 group than in M group (P<0.01 and P<0.05). TheNOS inhibitor Nw-nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats. CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOSderived NO.展开更多
AIM: To evaluate immunological protection of nitric ox- ide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation, METHODS: Sixty-six healthy m...AIM: To evaluate immunological protection of nitric ox- ide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation, METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipi-ent pairs). In group 11, organ preservation solution was lactated Ringer's solution with heparin 10 000/μL at 4℃. In groups I and 111, the pLeservation solution added, respectively, L-arginine or Ng-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group 11, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipi- ents. Five rats were used for observation of postopera- tive survival in each group. The other six rats in each group were used to obtain tissue samples, and execut- ed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-a and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by tri- phosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining. RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week sur- viral rate of grafted liver recipients in group I was significantly increased (28.8 4±36.6 d ys 4 4±1.7 d, P 〈 0.01) as compared with groups 11 and Ill. Serum levels of ALT in group ] were 2-7 times less than those in groups 11 and 11I (P 〈 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group 11 after 3 h and 24 h reperfusion, while in group ]]], they were significantly reduced as compared with those in group ]1 (P 〈 0.01). The levels of TNF-(z in group I were significantly lower than in group Ⅱ after 3 h and 24 h reperfusion (P 〈 0.01), while being sig- nificantly higher in group Ⅲ than group Ⅱ (P 〈 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe in- flammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient's lung tissues was signifi-cantly reduced in group I after 3 h and 24 h reperfu- sion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group Ⅱ but expres- sion of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group Ⅱ at 3 h after reperfusion. CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treat- ing hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation.展开更多
Objective: To investigate the effect of ischemic postconditioning (1PO) on acute lung ischemia-reperfusion (I/R) injury and the protein expression of haeme oxygenase-1 (HO-1), a cytoprotective defense against o...Objective: To investigate the effect of ischemic postconditioning (1PO) on acute lung ischemia-reperfusion (I/R) injury and the protein expression of haeme oxygenase-1 (HO-1), a cytoprotective defense against oxidative injury. Methods: After being anesthetized with chloralhydrate, forty-eight healthy SD rats were randomly divided into 6 groups (8 in each): sham operation group (S group); I/R group: left lung hilum was clamped for 40 minutes followed by 105 minutes of reperfusion; IPO group: left lung hilum was clamped for40 minutes and postconditioned by 3 cycles of 30 seconds of reperfusion and 30 seconds of reocclusion; Heroin (HM)+ I/R group: heroin, an inducer of HO-1 was injected intraperitoneally at 40 μmol·kg^-1·day^-1 for two consecutive days prior to 40 minutes clamping of left lung hilum; ZnPPIX+IPO group: zinc protoporphyrin IX, an inhibitor of HO-1 was injected intraperitoneally at 20 mg·kg^-1 24 hours prior to 40 minutes clamping of left lung hilum; and HM+S group: HM was administered as in the HM+I/R group without inducing lung I/R. Arterial partial pressure of oxygen (PaO2) and malondialdehyde (MDA) content in serum were assessed. The left lung was removed for determination of wet/dry lung weight ratio and expression of HO-1 protein by immuno-histochemical technique and for light microscopic examination. Results: The PaO2 was significantly lower in all the experimental groups compared with sham group (90 roan Hg ±11 mmHg). However, the values of PaO2in IPO (81 mm Hg±7 mm Hg) and HM+I/R (80 mm Hg±9 mm Hg) were higher than that in I/R (63 mm Hg±9 mm Hg) and ZnPPIX+IPO (65 mm Hg±8 mm Hg) groups (P〈0.01). The protein expression of HO- 1 in lung tissue was significantly increased in I/R group compared with S group (P〈0.01). While the HO-1 protein expression was higher in IPO and HM+I/R groups as compared with I/R group (P〈0.05, P〈0.01 ). The lung wet/ dry (W/D) weight ratio and MDA content in serum were significantly increased in I/R group as compared with S or HM+S groups (P〈0.01), accompanied by severe lung tissue histological damage, which was attenuated either by IPO or by HM pretreatment (P〈0.01, IPO or HM+I/R vs. I/R). The protective effect of IPO was abolished by ZnPPIX. Conclusion: Ischemic postconditioning can attenuate the lung ischemia-reperfusion injury through upregulating the protein expression of HO-I that leads to reduced postischemic oxidative damage.展开更多
文摘AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated withendothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO).METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-α levels, liver tissuemalondialdehyde (MDA) content, and severity of hepatic I/R injury.RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7±11.0 μmol/L vs 45.3±10.1μmol/L, P<0.01). Although serum NO levels decreased significantly after hepatic I/R (P<0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8±8.6 μmol/L vs 23.8±4.7 μmol/L, P<0.01). Serum ALT and TNF-α levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5±46.4 U/L, 0.99±0.11 μg/L and 0.57±0.10 μmol/g vs668.7±78.7 U/L, 1.71±0.18 μg/Land 0.86±0.11 μmol/g, respectively, P<0.01). I/R induced significant injury to the liver both in M and F groups (P<0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P<0.05 and P<0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P<0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-β- estradiol (E2) (M+E2 group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-α levels, and liver tissue MDA content after I/R (P<0.01).The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E2 group than in M group (P<0.01 and P<0.05). TheNOS inhibitor Nw-nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats. CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOSderived NO.
文摘AIM: To evaluate immunological protection of nitric ox- ide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation, METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipi-ent pairs). In group 11, organ preservation solution was lactated Ringer's solution with heparin 10 000/μL at 4℃. In groups I and 111, the pLeservation solution added, respectively, L-arginine or Ng-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group 11, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipi- ents. Five rats were used for observation of postopera- tive survival in each group. The other six rats in each group were used to obtain tissue samples, and execut- ed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-a and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by tri- phosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining. RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week sur- viral rate of grafted liver recipients in group I was significantly increased (28.8 4±36.6 d ys 4 4±1.7 d, P 〈 0.01) as compared with groups 11 and Ill. Serum levels of ALT in group ] were 2-7 times less than those in groups 11 and 11I (P 〈 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group 11 after 3 h and 24 h reperfusion, while in group ]]], they were significantly reduced as compared with those in group ]1 (P 〈 0.01). The levels of TNF-(z in group I were significantly lower than in group Ⅱ after 3 h and 24 h reperfusion (P 〈 0.01), while being sig- nificantly higher in group Ⅲ than group Ⅱ (P 〈 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe in- flammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient's lung tissues was signifi-cantly reduced in group I after 3 h and 24 h reperfu- sion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group Ⅱ but expres- sion of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group Ⅱ at 3 h after reperfusion. CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treat- ing hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation.
基金This project was supported by the National Natural Science Foundation of China (No.30672033).
文摘Objective: To investigate the effect of ischemic postconditioning (1PO) on acute lung ischemia-reperfusion (I/R) injury and the protein expression of haeme oxygenase-1 (HO-1), a cytoprotective defense against oxidative injury. Methods: After being anesthetized with chloralhydrate, forty-eight healthy SD rats were randomly divided into 6 groups (8 in each): sham operation group (S group); I/R group: left lung hilum was clamped for 40 minutes followed by 105 minutes of reperfusion; IPO group: left lung hilum was clamped for40 minutes and postconditioned by 3 cycles of 30 seconds of reperfusion and 30 seconds of reocclusion; Heroin (HM)+ I/R group: heroin, an inducer of HO-1 was injected intraperitoneally at 40 μmol·kg^-1·day^-1 for two consecutive days prior to 40 minutes clamping of left lung hilum; ZnPPIX+IPO group: zinc protoporphyrin IX, an inhibitor of HO-1 was injected intraperitoneally at 20 mg·kg^-1 24 hours prior to 40 minutes clamping of left lung hilum; and HM+S group: HM was administered as in the HM+I/R group without inducing lung I/R. Arterial partial pressure of oxygen (PaO2) and malondialdehyde (MDA) content in serum were assessed. The left lung was removed for determination of wet/dry lung weight ratio and expression of HO-1 protein by immuno-histochemical technique and for light microscopic examination. Results: The PaO2 was significantly lower in all the experimental groups compared with sham group (90 roan Hg ±11 mmHg). However, the values of PaO2in IPO (81 mm Hg±7 mm Hg) and HM+I/R (80 mm Hg±9 mm Hg) were higher than that in I/R (63 mm Hg±9 mm Hg) and ZnPPIX+IPO (65 mm Hg±8 mm Hg) groups (P〈0.01). The protein expression of HO- 1 in lung tissue was significantly increased in I/R group compared with S group (P〈0.01). While the HO-1 protein expression was higher in IPO and HM+I/R groups as compared with I/R group (P〈0.05, P〈0.01 ). The lung wet/ dry (W/D) weight ratio and MDA content in serum were significantly increased in I/R group as compared with S or HM+S groups (P〈0.01), accompanied by severe lung tissue histological damage, which was attenuated either by IPO or by HM pretreatment (P〈0.01, IPO or HM+I/R vs. I/R). The protective effect of IPO was abolished by ZnPPIX. Conclusion: Ischemic postconditioning can attenuate the lung ischemia-reperfusion injury through upregulating the protein expression of HO-I that leads to reduced postischemic oxidative damage.