Nonischemic Lobes Research Articles

Pathophysiological appraisal of an extracorporeal portosystemic shunt in total hepatic ischemia model in rats

Introduction: Animal models of total hepatic ischemia are restricted by concomitant splanchnic congestion from portal triad occlusion. This study was performed to clarify a pathophysiological advantages of an extracorporeal portosystemic shunt (PSS) in total hepatic ischemia model in rats. Methods- Using a polyethylene tube with 0.86 or 1 mm inner diameter, PSS was produced between the mesenteric vein and the jugular vein. A total hepatic ischemia model with PSS was compared with a partial ischemic model with hepatectomy of non-ischemic lobes as well as a total ischemic model without PSS. The well-tolerated ischemic period for the liver, portal pressure at 10 minutes after hepatic ischemia, portal endotoxin levels at 1 hour after reperfusion, and histological evaluation of the small bowel just before reperfusion and oxygen saturation index (ISO2) of the small intestinal blood through the experiment were assessed among the models. Results: Animals without PSS poorly tolerated 30 minutes of total hepatic ischemia with 88% mortality during 24 hours after reperfusion. Animals subjected to total hepatic ischemia with PSS or partial hepatic ischemia could tolerate a longer period of ischemia (60 minutes) with significantly higher ISO2 of the small intestine and lower portal pressure during ischemia, portal endotoxin levels 1 hour after reperfusion (p < 0.01), and less histological damage of the small bowel, when compared to those of the non-shunted total ischemia group. The groups of total hepatic ischemia with a shunt tube of 1 mm inner diameter and partial hepatic ischemia significantly prevented the elevation of portal endotoxin level, unlike that with a shunt tube of 0.86 mm inner diameter. Conclusions: Model of total hepatic ischemia with PSS of 1 mm inner diameter was strikingly similar to that of partial hepatic ischemia in pathophysiology during hepatic ischemia. Application of PSS tube of 1 mm or more inner diameter offers a pathophysiological advantage in the experiments of total hepatic ischemia and reperfusion.

Chemokine involvement in hepatic ischemia/reperfusion injury in mice: roles for macrophage inflammatory protein-2 and Kupffer cells.

Hepatic injury induced by ischemia and reperfusion is an important clinical problem after liver resection or transplantation. Neutrophils are known to mediate the organ injury, but the precise mechanisms leading to hepatic neutrophil recruitment are undefined. Two CXC chemokines, macrophage inflammatory protein-2 (MIP-2) and KC, are potently chemotactic for neutrophils in vitro and have been reported to be involved in neutrophil-dependent inflammatory tissue injury. The objective of the present study was to determine the roles of MIP-2 and KC in the induction of hepatic ischemia/reperfusion injury. C57BL/6 mice were subjected to 90 minutes of partial hepatic ischemia followed by reperfusion. Hepatic injury was associated with neutrophil sequestration, edema, and elevated serum levels of hepatic transaminases. The expression of MIP-2 messenger RNA (mRNA) was induced within 3 hours after reperfusion, before any detectable increase in neutrophil accumulation, and was also increased to a greater extent in the ischemic lobe after 9 hours of reperfusion. These data suggest that MIP-2 may be involved in the initial recruitment of neutrophils to the ischemic lobe. In contrast, KC mRNA expression was not increased after 3 hours of reperfusion but after 9 hours increased equivalently in both ischemic and nonischemic lobes, suggesting a more generalized role in neutrophil recruitment. Neutralization of MIP-2 or KC resulted in significant decreases in hepatic neutrophil accumulation, edema, and hepatocellular injury. These data suggest that the local expression of MIP-2 and KC are important mediators involved in neutrophil-dependent hepatic injury induced by ischemia and reperfusion in mice.

ICAM-1 upregulation in distant tissues after hepatic ischemia/reperfusion: A clue to the mechanism of multiple organ failure

Background/Purpose: Endothelial cell adhesion molecules (ECAMs) are felt to play an important role in ischemia/ reperfusion (I/R) injury by causing adhesion of leukocytes to endothelial cells. It is possible that ECAMs play a role in multiple organ system failure. ICAM-1 is one of the adhesion molecules that has been shown to be upregulated in response to cytokines. This upregulation leads to leukocyte endothelial cell interaction (adhesion) and to neutrophil infiltration of the affected tissue. The purpose of our study was to measure ICAM-1 expression in the liver and other organs after hepatic ischemia/reperfusion (I/R). Methods: A laparotomy was performed on 14 Sprague-Dawley rats; 45 minutes of occlusive ischemia to the left lateral lobe was followed by 5 hours of reperfusion. The rat was injected with I 125-labeled ICAM-1 MAb and I 131-labeled nonbinding MAb (to control for nonspecific accumulation of ICAM-1 MAb). Entire organs were harvested and accumulated activity was measured in each organ. ICAM-1 levels were expressed as percent injected dose per gram of tissue. Control animals underwent sham laparotomy. Results: ICAM-1 was upregulated in the ischemic lobe of the liver, nonischemic lobe of the liver, heart, kidney, intestine, and pancreas. Up-regulation in the lung was not significant. Both the lung and liver had high constitutive levels of ICAM-1. Conclusions: These data show that (1) significant hepatic upregulation of ICAM-1 after hepatic ischemia/reperfusion and (2) significant ICAM-1 upregulation in other tissues (heart, kidney, and intestine) after hepatic ischemia/reperfusion. The ICAM-1 upregulation in distant organs is likely mediated by cytokines such as tumor necrosis factor (TNF). These data show that leukocyte endothelial cell interactions in distant organs may be mediated by hepatic ischemia/ reperfusion. This is a possible explanation for how failure of one organ can lead to failure of others in multiple organ system failure.

Vascular occlusion in hepatic resections in cirrhotic rat livers: An experimental study in rats

The aim of this study was to evaluate the tolerance of normothermic liver ischemia with different degrees of hepatic function in cirrhotic rats. Liver cirrhosis was induced by administering carbon tetrachloride (CCl4) in water solution to male Wistar rats. Hepatic function was graded using the plasma levels of antithrombin III, albumin, and bilirubin and the presence of ascites. Rats were distributed in four groups: noncirrhotic (control group), compensated cirrhosis (group A), decompensated cirrhosis (group B), and decompensated cirrhosis with ascites (group C). Groups A, B, and C were significantly different in all four parameters studied (P < .003). Subtotal liver ischemia was performed for periods of 0, 30, 45, 60, and 75 minutes. At the end of the procedure, the nonischemic lobes were resected. Postoperative evolution of alanine aminotransferase, aspartate aminotransferase, and bilirubin levels was also recorded. Survival rates after the same periods of ischemia were statistically different (P < .05): control group, 7 of 7 after 45 minutes (100%), 7 of 7 after 60 minutes (100%), and 4 of 9 after 75 minutes (44%); group A, 7 of 7 after 45 minutes (100%) and 1 of 7 after 60 minutes (14%); group B, 7 of 7 after 0 minutes (100%), 5 of 7 after 30 minutes (71%), and 1 of 7 after 45 minutes (14%); and group C, 0 of 5 after 0 minutes (0%) and 1 of 7 after 30 minutes (14%). No differences were found in the postoperative course of transaminases. However, bilirubin levels found 24 hours and 7 days after ischemia were significantly greater in cirrhotic rats, and this was directly related to the degree of hepatic insufficiency (P < .001). Histological examination of the livers exposed to CCl4 showed features of liver cirrhosis with ductal proliferation. The ischemia time tolerated by cirrhotic rat livers is shorter than the time tolerated by normal rats. Tolerance to hilar vascular occlusion depends on the degree of hepatic insufficiency. Rats with decompensated cirrhosis and ascites do not tolerate any surgical procedure. (Liver Transpl Surg 1997 Nov;3(6):617-23)

Vascular occlusion in hepatic resections in cirrhotic rat livers: an experimental study in rats.

The aim of this study was to evaluate the tolerance of normothermic liver ischemia with different degrees of hepatic function in cirrhotic rats. Liver cirrhosis was induced by administering carbon tetrachloride (CCl4) in water solution to male Wistar rats. Hepatic function was graded using the plasma levels of antithrombin III, albumin, and bilirubin and the presence of ascites. Rats were distributed in four groups: noncirrhotic (control group), compensated cirrhosis (group A), decompensated cirrhosis (group B), and decompensated cirrhosis with ascites (group C). Groups A, B, and C were significantly different in all four parameters studied (P < .003). Subtotal liver ischemia was performed for periods of 0, 30, 45, 60, and 75 minutes. At the end of the procedure, the nonischemic lobes were resected. Postoperative evolution of alanine aminotransferase, aspartate aminotransferase, and bilirubin levels was also recorded. Survival rates after the same periods of ischemia were statistically different (P < .05): control group, 7 of 7 after 45 minutes (100%), 7 of 7 after 60 minutes (100%), and 4 of 9 after 75 minutes (44%); group A, 7 of 7 after 45 minutes (100%) and 1 of 7 after 60 minutes (14%); group B, 7 of 7 after 0 minutes (100%), 5 of 7 after 30 minutes (71%), and 1 of 7 after 45 minutes (14%); and group C, 0 of 5 after 0 minutes (0%) and 1 of 7 after 30 minutes (14%). No differences were found in the postoperative course of transaminases. However, bilirubin levels found 24 hours and 7 days after ischemia were significantly greater in cirrhotic rats, and this was directly related to the degree of hepatic insufficiency (P < .001). Histological examination of the livers exposed to CCl4 showed features of liver cirrhosis with ductal proliferation. The ischemia time tolerated by cirrhotic rat livers is shorter than the time tolerated by normal rats. Tolerance to hilar vascular occlusion depends on the degree of hepatic insufficiency. Rats with decompensated cirrhosis and ascites do not tolerate any surgical procedure.

Ischemia-reperfusion activates the nuclear transcription factor NF-κB and upregulates messenger RNA synthesis of adhesion molecules in the liver in vivo

Hepatic ischemia-reperfusion induces a neutrophil-induced injury, which is dependent on adhesion molecules. The transcription factor NF-κB plays a key role in the activation of adhesion molecule gene expression in vitro. To investigate activation of NF-κB and initiation of adhesion molecule gene transcription in the liver in vivo, Fischer rats were subjected to 30 min of hepatic ischemia and up to 24 h of reperfusion. A moderate baseline activation of NF-κB was found in the liver in sham-operated controls and during ischemia, however, at 1 h and 5 h reperfusion, nuclear NF-κB DNA-binding activity increased by 270–300% as determined by densitometric analysis of electrophoretic mobility shift assays. At 24 h, NF-κB was still activated by 140% above sham control levels. NF-κB complexes consisted of subunits p50 and p65 (RelA). In addition, nuclear translocation of the transcription factor C/EBPβ was increased during reperfusion. Northern blot analysis of RNA isolated from the intact liver showed minor intercellular adhesion molecule-1 (ICAM-1) mRNA expression in sham controls, a moderate but significant increase during ischemia and a further significant increase during reperfusion. Isolation of hepatic endothelial cells demonstrated transiently increased gene transcription for ICAM-1, vascular adhesion molecule-1 (VCAM-1), E-and P-selectin at 1 h reperfusion. In the nonischemic lobes a similar time course of NF-κB activation and ICAM-1 mRNA formation was observed during reperfusion suggesting the involvement of circulating mediators. The data support the conclusion that hepatic ischemia-reperfusion induces NF-κB and C/EBPβ activation and enhances transcription of cellular adhesion molecule genes in the liver.

Expression of c-fos and c-jun during hepatocellular remodeling following ischemia/reperfusion in mouse liver.

The expression of the immediate early genes (IEGs) c-fos and e-jun have been hypothesized to potentially play key roles in mediating cellular responses following injury to the liver. In this study, we sought to evaluate the potential involvement of c-jun and c-fos as determinants either of cellular regeneration or programmed cell death following ischemia/reperfusion (I/R) in mouse liver. To this end, we have analyzed the in situ messenger RNA (mRNA) expression patterns of c-jun and c-fos following lobar I/R in mouse liver. The expression patterns of c-jun and c-fos were correlated with four criteria for tissue repair and injury, including: 1) morphological determinations of regeneration using immunocytochemical detection of proliferating cell nuclear antigen (PCNA), 2) programmed cell death (apoptosis) using the in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method, 3) histopathologic assessment of hepatocellular necrosis, and 4) serum glutamic pyruvic transaminase (GPT) levels. Increasing lengths of lobar ischemia for 3, 60, and 90 minutes followed by reperfusion directly correlated with the extent of liver injury as determined by serum transaminases and hepatocellular necrosis. PCNA expression in the liver was elevated at 1 to 6 hours following liver reperfusion and returned to baseline levels by 20 hours in both ischemic and nonischemic lobes. In contrast, apoptotic responses peaked only in ischemic lobes at 6 hours' postreperfusion and remained elevated out to 20 hours. Two distinct patterns of c-jun and c-fos expression were observed during the acute (1-3 hours) and subacute (6-20 hours) phases of liver responses to I/R including: 1) coexpression of c-jun and c-fos mRNA within damaged regions of the liver at 1 to 3 hours' postreperfusion, and 2) a decline in c-fos expression with sustained high levels of c-jun expression within a subset of cells bordering necrotic/apoptotic regions of the liver at 6 to 20 hours' postreperfusion. These findings suggest that coexpression of both c-jun and c-fos may be involved in mediating early tissue repair processes in liver remodeling following I/R. In contrast, the onset of hepatocellular apoptosis correlated with sustained c-jun expression, in the absence of c-fos, and suggests that these changes in the molecular profile of immediate early gene expression may regulate cellular responses that signal hepatocytes for programmed cell death.

Expression of c-fos and c-jun during hepatocellular remodeling following ischemia/reperfusion in mouse liver

The expression of the immediate early genes (IEGs) c-fos and e-jun have been hypothesized to potentially play key roles in mediating cellular responses following injury to the liver. In this study, we sought to evaluate the potential involvement of c-jun and c-fos as determinants either of cellular regeneration or programmed cell death following ischemia/reperfusion (I/R) in mouse liver. To this end, we have analyzed the in situ messenger RNA (mRNA) expression patterns of c-jun and c-fos following lobar I/R in mouse liver. The expression patterns of c-jun and c-fos were correlated with four criteria for tissue repair and injury, including: 1) morphological determinations of regeneration using immunocytochemical detection of proliferating cell nuclear antigen (PCNA), 2) programmed cell death (apoptosis) using the in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method, 3) histopathologic assessment of hepatocellular necrosis, and 4) serum glutamic pyruvic transaminase (GPT) levels. Increasing lengths of lobar ischemia for 3, 60, and 90 minutes followed by reperfusion directly correlated with the extent of liver injury as determined by serum transaminases and hepatocellular necrosis. PCNA expression in the liver was elevated at 1 to 6 hours following liver reperfusion and returned to baseline levels by 20 hours in both ischemic and nonischemic lobes. In contrast, apoptotic responses peaked only in ischemic lobes at 6 hours' postreperfusion and remained elevated out to 20 hours. Two distinct patterns of c-jun and c-fos expression were observed during the acute (1-3 hours) and subacute (6-20 hours) phases of liver responses to I/R including: 1) coexpression of c-jun and c-fos mRNA within damaged regions of the liver at 1 to 3 hours' postreperfusion, and 2) a decline in c-fos expression with sustained high levels of c-jun expression within a subset of cells bordering necrotic/apoptotic regions of the liver at 6 to 20 hours' postreperfusion. These findings suggest that coexpression of both c-jun and c-fos may be involved in mediating early tissue repair processes in liver remodeling following I/R. In contrast, the onset of hepatocellular apoptosis correlated with sustained c-jun expression, in the absence of c-fos, and suggests that these changes in the molecular profile of immediate early gene expression may regulate cellular responses that signal hepatocytes for programmed cell death. (Hepatology 1996 Jun;23(6):1546-55)

Protective Effects of .ALPHA.-Tocopherol against Glucose Intolerance and Mitochondrial Damage in Reperfused Rat Liver.

We examined the protective effects of α-tocopherol against glucose intolerance and mitochondrial damage in rat liver after partial in vivo ischemia and reperfusion, while glucose was intravascularly supplemented. Rats were given α-tocopherol or vehicle for three consecutive days before the experiment. Left and median lobes of the liver received 90-min ischemia and 60-min reperfusion. Besides plasma levels of glucose, insulin, and lipid peroxide, we also measured oxidative phosphorylation, cytochrome c oxidase (CCO) activity, and lipid peroxide levels in mitochondria in both ischemic and non-ischemic lobes of the liver in control and α-tocopherol groups before and at the end of ischemia and after reperfusion. Both plasma glucose and insulin levels after reperfusion were lower in the α-tocopherol-treated group than in the control group. Ischemia markedly suppressed both mitochondrial respiration supported by succinate and CCO activity in the ischemic lobes in both groups. Reperfusion recovered mitochondrial function and CCO activity better in the α-tocopherol-treated group than in the control group, whereas the lipid peroxide levels in both plasma and mitochondria were significantly lower in the α-tocopherol-treated group. In non-ischemic lobes, ischemia-reperfusion slightly accelerated both the oxidative phosphorylation rate (OPR) and CCO activity, whereas lipid peroxide levels were unaffected. The results suggest that glucose intolerance during the early phase of reperfusion was not due to lowered plasma insulin level, but might be related to liver damage, as assessed in terms of mitochondrial functions, in the ischemic lobes. α-Tocopherol could protect against mitochondrial damage and glucose intolerance. Oxidative phosphorylation in non-ischemic lobes likely compensated for the decreased mitochondrial activity in the ischemic lobes during ischemia and reperfusion.

Intercellular adhesion molecule 1 (ICAM-1) expression and its role in neutrophil-induced ischemia-reperfusion injury in rat liver

The potential role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of reperfusion injury was investigated in male Fischer rats subjected to 45 min of hepatic ischemia and 24 h of reperfusion. ICAM-1 mRNA levels increased during ischemia in the ischemic liver lobes; however, during reperfusion mRNA levels increased in both the ischemic and nonischemic lobes. Immunohistochemical evaluation indicated ICAM-1 expression only on sinusoidal lining cells in controls; ischemia-reperfusion enhanced ICAM-1 expression in the sinusoids and induced some expression on hepatocytes. The monoclonal anti-ICAM-1 antibody 1A29, but not an immunoglobulin G control antibody, administered at 1 h and 8 h of reperfusion (2 mg/kg) significantly attenuated liver injury as indicated by 51% lower plasma alanine aminotransferase activities and 32-36% less hepatic necrosis at 24 h without affecting reactive oxygen formation by Kupffer cells and hepatic neutrophils. Although 1A29 reduced neutrophil extravasation in a glycogen peritonitis by 60%, the antibody had no significant effect on hepatic neutrophil infiltration during reperfusion. These data suggest that ICAM-1 plays a significant role during the neutrophil-dependent injury phase after hepatic ischemia and reperfusion and therefore blocking this adhesion molecule may have therapeutic potential against postischemic acute liver failure.

Hepatic ischemia/reperfusion injury: importance of oxidant/tumor necrosis factor interactions.

Previous studies have demonstrated a role for both tumor necrosis factor (TNF) and reactive oxygen intermediates (ROI) in hepatic ischemia/reperfusion (I/R) injury. Biologically active TNF was present in liver homogenates in ischemic and nonischemic lobes after 2 h of ischemia but without reperfusion. Using an in situ liver perfusion model, we measured ROI, TNF, and hepatic enzymes in the effluent after 2 h of ischemia. Increased reduction of ferricytochrome C was observed in the hepatic effluent, indicative of the formation of ROI. Treatment of animals with TNF neutralizing antisera significantly reduced both ROI and aspartate aminotransferase (AST). Animals treated with superoxide dismutase (SOD), or SOD + catalase (CAT) had greater TNF in the hepatic effluent compared with I/R alone; however, SOD or SOD + CAT did not cause additional release of AST.SOD + CAT plus anti-TNF serum resulted in significant protection compared with SOD + CAT plus control serum. Reperfusion of ischemic liver with 4 mM H2O2 increased both TNF and AST. Optimal protection of hepatocellular injury from reperfusion injury is achieved with a combination of antioxidants and inhibition of TNF.

Modulation of ischemia-reperfusion-induced hepatic injury by Kupffer cells.

To elucidate the role of Kupffer cells in ischemia-reperfusion-induced hepatic injury, hepatic injury induced by ischemia-reperfusion was analyzed after modulation of Kupffer cell function. Ischemia of the liver was performed by occlusion of both the portal vein and hepatic artery, which enter into the left lateral and median lobes of the liver. Blood flow in the ischemic lobe was reduced, in contrast to an increased blood flow in the nonischemic lobe during occlusion of the veins. Although hepatocyte damage was not demonstrated by ischemia for < 60 min, hepatic injury was found after reperfusion of the liver, and activation of Kupffer cells was morphologically demonstrated by electron microscopies. Suppression of Kupffer cells, induced by previous administration of gadolinium chloride or latex particles, reduced the grade of hepatic injury induced by ischemia-reperfusion. On the other hand, stimulation of Kupffer cell phagocytosis, induced by administration of latex particles at the time of reperfusion, aggravated the ischemia-reperfusion-induced hepatotoxicity, which was then reduced by simultaneous administration of superoxide dismutase. Kupffer cells, isolated from the rats treated with the ischemia-reperfusion procedure, have been found to release increased amounts of oxygen radical intermediates. These results suggest that hepatic injury induced by ischemia-reperfusion is modulated by the function of Kupffer cells and that superoxide anion released from Kupffer cells could play an important role in ischemia-reperfusion hepatic injury.

Filtration coefficient in isolated preserved and reperfused canine lung

The filtration coefficient ( K f) in Starling's equation for fluid exchange was estimated in isolated reperfused canine lobes to evaluate the effect of ischemia-reperfusion injury on alveolar-capillary permeability quantitatively and to determine the inhibitory effects of a high dose of methylprednisolone (MPS) or dimethylthiourea (DMTU), a potent hydroxyl radical scavenger, on this injury. We reperfused isolated canine left lower lobes (LLLs) with blood at a constant flow after 3 hr of warm (38°C) or cold (4°C) ischemia and measured K f after 1 hr of reperfusion. The mean value of K f (±1 SD) in the cold ischemic lobes (COLD, n = 7), 0.13 ± 0.04 g·min −1·cmH 2O −1·100 g −1, was not different from that in the control nonischemic lobes (CONT, n = 6), 0.10 ± 0.04 g·min −1·cmH 2O −1·100 g −1. In contrast, the mean value of the K f in the warm ischemic lobes (WARM, n = 7), 0.38 ± 0.17 g·min −1·cmH 2O −1·100 g −1, was significantly ( P < 0.001) higher than in CONT. MPS (30 mg/Kg) or DMTU (0.75 g/kg) administered before isolation of LLL and before reperfusion reduced the increase in K f in warm ischemic lobes to 0.19 ± 0.09 and 0.19 ± 0.05 g·min −1·cmH 2O −1·100 g −1, respectively ( P < 0.005 WARM vs MPS, and P < 0.01 WARM vs DMTU). MPS and DMTU also attenuated the impairment of gas exchange. We conclude that (1) reperfusion after 3 hr of warm ischemia increases K f but after cold ischemia does not, and (2) MPS and DMTU prevent the increase in K f. Our data suggest that the ischemic-reperfusion lung injury may be due in part to the hydroxyl radical and some pharmacological agents can prevent the injury by attenuating increase in pulmonary microvascular permeability.

Effects of partial ischemia and reflow on mitochondrial metabolism in rat liver.

To clarify the effects of partial ischemia and reflow on the mitochondrial metabolism of the rat liver, the afferent vessels supplying the left lateral and left half of medial lobes were occluded and then reperfused after given time periods of ischemia (30, 60, 90 and 120 min, groups A, B, C and D, respectively). Samplings were taken at 0, 10 and 60 min after reperfusion. The energy charge levels of ischemic lobes decreased rapidly from 0.85 +/- 0.01 in the sham group to 0.38 +/- 0.11, 0.35 +/- 0.07 and 0.34 +/- 0.06 in groups B, C and D, respectively. The phosphorylative activities of mitochondria isolated from ischemic lobes decreased gradually along with the time of ischemia. The reversal of mitochondrial function and energy charge levels following reperfusion was noted in groups A and B. In nonischemic lobes, the phosphorylation rate (nmol ATP/mg/min) increased from 90 +/- 6 in sham group to 125 +/- 12 and 130 +/- 9; 131 +/- 5 and 130 +/- 6; 123 +/- 6 and 122 +/- 17, and 138 +/- 6 and 138 +/- 13 at 10 and 60 min after reflow in groups A, B, C and D, respectively (p less than 0.05). The energy charge level of nonischemic lobes decreased from 0.85 +/- 0.01 of sham group to 0.80 +/- 0.03 in group D (p less than 0.05). From these results, it is concluded that the transitional zone for the reversal of mitochondria function and energy metabolism following prolonged liver ischemia appears at around 60 min.(ABSTRACT TRUNCATED AT 250 WORDS)