[Influence of oxidative stress on apoptosis and expression of bax and bcl-2 of enterocytes in burn rats with delayed resuscitation on the plateau].

OBJECTIVE: To explore influence of oxidative stress reaction on apoptosis rate and expression of apoptosis-related genes bax and bcl-2 of enterocytes in severely burned rats with delayed resuscitation on the plateau. METHODS: One hundred and twenty rats subjected to 30% TBSA full-thickness scald on the back were devided into plateau experimental group (PE, altitude 3840 m) and Lanzhou experimental group (LE, altitude 1517 m). Then LE and PE groups were subdivided into Lanzhou immediate fluid resuscitation group (LIFR, with immediate intraperitoneal injection of isotonic saline after scald, 40 mL/kg), Lanzhou delayed fluid resuscitation group [LDFR, with intraperitoneal injection of isotonic saline at 6 post scald hour (PSH), 40 mL/kg], and plateau immediate fluid resuscitation group (PIFR, with immediate intraperitoneal injection of isotonic saline after scald, 40 mL/kg), plateau delayed fluid resuscitation group (PDFR, with intraperitoneal injection of isotonic saline at 6 PSH, 40 mL/kg). Another 12 rats were divided into Lanzhou sham scald group (LS) and plateau sham scald group (PS), with 6 rats in each group. Rats in LS and PS groups were sham scalded in a water bath for 15 s without fluid infusion. Rats were sacrificed at 6, 12, 24, 48, 72 PSH for collection of small intestine samples to determine the contents of malonaldehyde (MDA) and total hydrosulfide (TSH). The apoptosis of enterocytes was determined by TUNEL, and the expression of bax and bcl-2 in epithelial cells were observed by immunohistochemical method. Intestinal sample of LS and PS groups were collected to determine the contents of MDA and TSH. RESULTS: After being scalded, content of MDA in intestinal tissue of rats in LDFR group and PDFR group was respectively greater than that in LIFR group and PIFR group (P < 0.05 or P < 0.01). Intestinal tissue content of MDA of rats in LDFR group (9.8 +/- 4.0 nmol/mg) and PDFR group (10.2 +/- 1.3 nmol/mg) was respectively greater than that in LIFR group (9.5 +/- 2.7 nmol/mg) and PIFR group (9.6 +/- 1.1 nmol/mg) (P < 0.05) at 24 PSH. After being scalded, intestinal content of TSH of rats in PE group and PDFR group was respectively smaller than that in LE group and LIFR group (P < 0.05). A multitude of brown positive apoptotic cells were observed in PDFR at 6 and 12 PSH. Absorbance values in LDFR group, PIFR group, and PDFR group were higher than that in LIFR group at each time point (P < 0.05 or P < 0.01). A multitude of bax positive cells were observed in intestinal mucous membrane in PDFR at 6 and 12 PSH. Expression of bal-2 was negative in PE group, and LIFR and LDFR groups at 6, 12 PSH, and it was weakly positive in LIFR and LDFR groups at 24, 48, 72 PSH. CONCLUSIONS: Enhancement of bax expression and weakening of bcl-2 expression in enterocytes are induced by the severe oxidative stress reaction in intestinal mucous membrane after burn with delayed resuscitation on the plateau, which may be one of the important reasons in inducing an increase in apoptosis of enterocytes.

[The influence of hypoxia inducible factor-1 alpha expression on apoptosis and proliferation of T lymphocyte in the Peyer's patches after burn with delayed fluid resuscitation in rats at high altitude].

OBJECTIVE: To explore the influence of hypoxia inducible factor-1 alpha (HIF-1 alpha) expression on the apoptosis and proliferation of T lymphocyte after severe burn with delayed fluid resuscitation at different altitude in rats. METHODS: One hundred and thirty-two Wistar rats were subjected to burn injury [30% total body surface area (TBSA), III degree], at 1,517 metres and 3,848 metres above sea level, and they were randomly divided into three groups: delayed fluid resuscitation group (DFR, n=30 at each altitude), immediate fluid resuscitation group (IFR, n=30 at each altitude), and sham group (SG, n=6). The Peyer's patches were harvested from the ileum of rats at 6, 12, 24, 48 and 72 hours after burn respectively. The levels of HIF-1 alpha, CD3(+) and the rate of apoptosis in Peyer's patches were detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), tissue microarray technology and immunohistochemistry. RESULTS: The apoptosis rate in Peyer's patches was higher in DFR group than that in IFR group. The increase in HIF-1 alpha expression was observed mainly on cell nucleus in T lymphocytes. The expression levels of HIF-1 alpha in Peyer's patches were much higher in DFR group and IFR group than those in SG, and they were higher at 3 848 metres than those at 1 517 metres, and also higher in DFR group compared with IFR group (all P<0.05). The decrease in CD3(+) expression was observed mainly on cell membrane in T lymphocytes. The expression levels of CD3(+) in Peyer's patches were much higher in DFR group and IFR group than those in SG group, and the trough value appeared at 12 hours after burn (all P<0.05). CONCLUSION: High expression of HIF-1 alpha may be responsible for the high apoptosis rate and decrease of T lymphocyte number in Peyer's patches after severe burn with delayed fluid resuscitation in rats at high altitude.

[Cell apoptosis and expression of hypoxia-inducible transcription factor-1 alpha in kidney tissue after severe burn with delayed fluid resuscitation in rats in areas of different altitude].

OBJECTIVE: To explore the relationship of cell apoptosis and expression regularity of hypoxia-inducible transcription factor (HIF)-1 alpha after severe burn with delayed fluid resuscitation in areas of different altitude. METHODS: A total of 240 male Wistar rats, which were raised in areas of different altitude (1,517 and 3,840 meters), were employed as the experimental models [They received a 30% total body surface area (TBSA)III degree scald injury], and then they were randomly divided into 3 groups: delayed fluid resuscitation group (DFR, n=50), immediate fluid resuscitation group (IFR, n=60) and control group (CG, n=10). Renal tissue samples were harvested at 1, 6, 12, 24, 72 and 168 hours after burn, respectively. Cell apoptosis was detected by tissue chip technology and terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling (TUNEL). The expression of HIF-1 alpha was assessed by immunohistochemistry and image analysis. RESULTS: With increase in altitude, cellular edema, degeneration, necrosis and disintegration of renal tissue were gradually worsening, the capillaries of renal glomeruli became dilated and engorged, with degeneration and necrosis of endothelial cells, engorgement and edema of renal interstitium, and infiltration of inflammatory cells. Pathological changes in DFR group were more serious than that of IFR group. Cell apoptosis and the expression of HIF-1 alpha were both enhanced, the latter mainly appeared in nuclei of renal cells, and they were more marked at 3,840 meters compared with those at 1,517 meters. They were more marked in experimental groups than in control group, especially so in DFR group (P<0.01). Cell apoptosis was positively correlated with the expression of HIF-1 alpha (r= -0.651, P<0.01). CONCLUSION: Severe burn at high attitude plateau results in high expression of HIF-1 alpha and an increase in apoptosis of renal cells. HIF-1 alpha plays a role in kidney cell apoptosis.

[The clinical significance of leucocytosis and increase in interleukin content in acute mountain sickness complicated with multiple organ dysfunction syndrome].

OBJECTIVE: To study the role of white blood cell (WBC) and interleukins (ILs) in acute mountain sickness (AMS) complicated with multiple organ dysfunction syndrome (MODS). METHODS: Three thousand one hundred and eighty-four patients suffering from severe AMC in the past 50 years were surveyed with questionnaire. Correlation analysis was done to explore the relationship between differential count of WBC and elevation of ILs contents and MODS. RESULTS: There was no difference in differential count of WBC between essential high altitude pulmonary edema (HAPE) and secondary HAPE. No difference was also found between simple HAPE and high altitude cerebral edema (HACE). However, obvious difference in WBC was found between HACE accompanied by HAPE and simple HAPE or simple HACE in the differential counts of WBC, counts of WBC and neutrophil were significantly elevated, while lymphocyte was significantly declined (all P < 0.05). The count of WBC in people suffering from AMS accompanied by MODS was higher than patients only suffering from AMS, lymphocyte was significantly decreased, the difference was obviously (both P < 0.01). The content of tumor necrosis factor-alpha (TNF-alpha), IL-1, IL-2, IL-6 and IL-8 of severe AMS patients were obviously higher than that of normal people, therefore the content of IL-4 in severe AMS patients was obviously lower than that normal people the difference were obvious (all P < 0.01). CONCLUSION: People suffering from AMS also exist systemic inflammatory response syndrome (SIRS). SIRS play an important part in MODS which is a major cause of AMS, and it's a critical factor of high altitude MODS.

[Analysis of 3,184 cases with acute mountain sickness complicated by multiple organ dysfunction syndrome].

OBJECTIVE: To investigate and analyze the probability of acute mountain sickness (AMS) [including high-altitude cerebral edema (HACE) and high-altitude pulmonary edema (HAPE)] complicated by multiple organ dysfunction syndrome (MODS) and its pathogenetic mechanisms. METHODS: Questionnaire survey was made to retrospectively study the hospitalization cases in the past 50 years, and the incidence of high-altitude MODS (H-MODS) were statistically analyzed to determine the main causes and pathogenic mechanism of MODS. RESULTS: Among 3 184 cases with severe AMS, 83 cases conformed to the diagnostic criteria of diagnosis of H-MODS, and the incidence was 2.6%. The pathogenesis of acute H-MODS might be related to the activation of inflammation pathways, activation of blood clotting pathways and the damage to gastrointestinal mucosa barrier. Therefore, improving the diagnosis and the treatment effects of H-MODS is an important measure to increase cure rate of AMS and to decrease its death rate. CONCLUSION: AMS complicated by multiple organ damage (MOD) is the main factor that influences the therapeutic efficacy. Prompt effective remedy on the spot is a significant measure to reduce incidence of MOD.

[Acute high altitude reaction syndrome and systemic inflammatory response syndrome].

Critical care medicine (CCM) is one of the challenging issue in clinical practice. The key issues of CCM include acute lung injury, acute respiratory distress syndrome, and multiple organ dysfunction syndrome (MODS), generally termed as systemic inflammatory response syndrome (SIRS). When SIRS occurs at high altitude areas (H-SIRS), it will need be distinguished with an idiopathic acute high altitude sickness (generally termed as acute high altitude reaction syndrome), that make the differential diagnosis and treatment of H-SIRS even more difficult. It has became a high priority to properly address the relevant issues in this field: construction of disciplines; identification of speciality scopes; standardization of the diagnosis and treatment of CCM; and decreasing of the mortality of MODS at high altitude.

Rosiglitazone, a peroxisome proliferator-activated receptor-gamma agonist, reduces acute lung injury in endotoxemic rats.

OBJECTIVE: Rosiglitazone, a potent agonist of peroxisome proliferator-activated receptor (PPAR)-gamma, exerts anti-inflammatory effects in vitro and in vivo. This study was designated to determine the effects of rosiglitazone on endotoxin-induced acute lung injury in rats. DESIGN: Prospective, experimental study. SETTING: University research laboratory. SUBJECTS: Thirty-six male Wistar rats. INTERVENTIONS: All the animals were randomly assigned to one of six groups (n = 6 per group) and were given either lipopolysaccharide (6 mg/kg intravenously) or saline, pretreated with rosiglitazone (0.3 mg/kg intravenously) or vehicle (10% dimethyl sulphoxide) 30 mins before lipopolysaccharide. The selective PPAR-gamma antagonist GW9662 (0.3 mg/kg intravenously) or its vehicle (10% dimethyl sulphoxide) was given 20 mins before rosiglitazone. MEASUREMENTS AND MAIN RESULTS: Endotoxemia for 4 hrs induced evident lung histologic injury and edema, both of which were significantly attenuated by rosiglitazone pretreatment. The protective effects of rosiglitazone were correlated with the reduction by 71% of the increase of myeloperoxidase activity and the reduction by 84% of the increase of malondialdehyde in the lung tissue. The pulmonary hyperproduction of nitric oxide was reduced by 82% of the increase related to lipopolysaccharide challenge. Pretreatment with rosiglitazone also markedly suppressed lipopolysaccharide-induced expression of inducible nitric oxide synthase messenger RNA and protein in the lung, as demonstrated by reverse transcription-polymerase chain reaction or Western blot analysis. Immunohistochemical analysis revealed that rosiglitazone inhibited the formation of nitrotyrosine, a marker for peroxynitrite reactivity, in the lung tissue. In addition, the specific PPAR-gamma antagonist GW9662 antagonized the effects of rosiglitazone. CONCLUSIONS: This study provides evidence, for the first time, that the PPAR-gamma agonist rosiglitazone significantly reduces endotoxin-induced acute lung injury in rats.

[Multiple organ dysfunction scoring system: comparison and evaluation of correlation and accuracy of the three scoring systems in predicting the outcome of multiple organ dysfunction syndrome on highland].

OBJECTIVE: To study the characteristics of the diagnostic parameters of acute respiratory distress syndrome/multiple organ dysfunction syndrome on plateau (H-ARDS/MODS) and compare the accuracy of the three MODS scoring criteria in predicting the outcome of syndrome. METHODS: Five hundred and forty cases fulfilling the criteria of MODS were divided into four groups according to the altitude of their inhabitation area: control group (on plain, CG, n=113, altitude: <430 m), moderate high altitude group 1 (H1G, n=314, altitude: 1,517 m), moderate high altitude group 2 (H2G, n=78, altitude: 2,261 m to 2,400 m) and high altitude group (HG, n=35, altitude: 2 808 m to 3 400 m). According to the diagnostic criteria of Lushan conference and Marshall (1995) commonly used on plain, and Lanzhou criteria drafted by the authors, three data analyzing models were set up to draw the receiver operating characteristic (ROC) curves, the Yordon Index and the optimum cutoff points of the parameters were calculated and the accuracy of the three respective diagnostic criteria was evaluated in predicting the outcome of ARDS/MODS. Multiple factors affecting the outcome of MODS were analyzed using the method of stepwise forward regress model. RESULTS: Following the increase in altitude, Lanzhou criteria was clearly superior to the other two criteria in the area of ROC, the sensitivity, the specificity, and also for the optimum cutoff points of MODS. Multi-variable regression analysis showed that the impacting factor of Lanzhou criteria was the highest (P<0.05). CONCLUSION: (1)Some parameters of the current diagnostic criteria of ARDS/MODS are not suitable in moderately high or high altitude areas. It is necessary to set up the diagnostic criteria of H-ARDS/MODS. (2)Some clinical characteristics might change in areas 1,500 m altitude or higher. The pathophysiological mechanism might be attributable to peculiar biologic reactions due to hypoxia stress reaction, and it is worth further study.

[Criteria suitable for diagnosis of acute respiratory distress syndrome/multiple organ dysfunction syndrome at moderately high altitude area].

OBJECTIVE: To compare the diagnostic parameters of acute respiratory distress syndrome/multiple organ dysfunction syndrome (ARDS/MODS) at high altitude (H-ARDS/MODS) with that on plain, and to establish a more practical diagnostic criterion of H-ARDS/MODS. METHODS: Five hundred and five cases fulfilled the criteria for the diagnosis of ARDS/MODS were divided into three groups according to the altitude of their habitation: control group including inhabitants (<430 m) on plain (CG, n=113), moderate high altitude group 1 inhabitants at the altitude of 1,517 m (H1G, n=314), moderate high altitude group 2 inhabitants at the altitude of 2,261 m to 2,400 m (H2G, n=78). The ARDS/MODS scores of the three groups were made according to the diagnostic criteria of Lushan conference, Marshall(1995) and Lanzhou criteria drafted by the authors respectively to set up three data analyzing models, followed by plotting of receiver operating characteristic curves (ROC curve) and calculation of the Yordon Index and the optimum cutoff points of the parameters,in order to study the accuracy of the three diagnostic criteria in predicting the outcome of the patients suffering from ARDS/MODS. RESULTS: In CG group, the differences were not significant in area of ROC, the maximal Yordon Index, the optimum cutoff points and the sensitivity and the specificity for three criteria; but the differences were significant for the three criteria in H1G group. Further investigation in comparing the ROC values of lung, brain, heart and kidney, the Lanzhou criteria were more advantageous in the high altitude than the other criteria. CONCLUSION: (1)The current diagnostic criteria of ARDS/MODS are not suitable for the diagnosis of these syndromes in moderately high or high altitude areas. It is necessary to revise the diagnostic criteria of H-ARDS/MODS. (2)One thousand five hundred and seventeen meters in altitude might be considered to be an important borderline, above with the diagnostic criteria of ARDS/MODS for patients inhabiting on plain could not be suitably applied to those living above this level.

[Changes in endothelin-1 and calcitonin gene-related peptide in myocardium after severe burn and delayed fluid resuscitation in rats at different altitudes on plateau].

OBJECTIVE: To explore changes in endothelin-1 (ET-1) and calcitonin gene-related peptide (CGRP) in the myocardium after severe burn and delayed fluid resuscitation in rats at different altitudes. METHODS: Two hundred and forty male Wistar rats were employed as the experimental models with full-thickness burn of 30% total body surface area (TBSA), and they were randomly divided into three groups: delayed fluid resuscitation group (DFR), immediate fluid resuscitation group (IFR) and control group (CG). Samples of myocardial tissue were harvested at 1 hour, 6 hours, 12 hours, 24 hours, 72 hours, 168 hours postburn respectively. The changes in ET-1 and CGRP contents were determined by means of radio immunological assay. RESULTS: (1)The contents of ET-1 and CGRP in DFR group tended to increase at 6 hours after burn, ET-1 was higher 2.8, 3.6 fold, while CGRP higher by 2.2, 1.5 fold (P<0.01), compared with that of CG respectively at 1517 m and 3840 m. The tendency of rise of ET-1 and CGRP was significantly less conspicuous in IFR group than that in DFR group. (2)The contents of ET-1 in DFR group tended to increase at 6 hours and reached the peak at 24 hours after burn at 1517 m, while the levels reached the peak at 72 hours after burn at 3840 m, and the change lasted for 168 hours in DFR group. The contents of CGRP increased significantly at 6 hours and reached the peak at 12 hours at 1517 m, while they reached the peak at 72 hours after burn at 3840 m. CONCLUSION: The myocardial contents of ET-1 tend to increase significantly with the elevation of altitude after severe burn in rats, but the contents of CGRP increased lagged behind. The result show that the higher the altitude is, the more the exhaustion of protective agents of the myocardium, thus resulting in changes in ET-1/CGRP.

[Preventive and treatment effect of composite Rhodiolae on acute lung injury in patients with severe pulmonary hypertension during extracorporeal circulation].

OBJECTIVE: To investigate the possibility of early prevention and treatment of acute lung injury by using composite Rhodiolae (CR) in patients with severe pulmonary hypertension during extracorporeal circulation. METHODS: Seventy-six patients with severe pulmonary hypertension screened out by color 2D-Doppler ultrasonography were randomly divided into the treated group (n = 40) and the control group (n = 36). The general treatment for the two groups, including preoperational preparation, operational procedure and conventional drug therapy, was the same. To the treated group, CR was administered 4 g every day (half the dose in children) at 7-10 day before and 5-7 day after the operation. The life signs, pulmonary ventilation parameters, arterial blood gas analysis were monitored and blood levels of TXB2, 6-keto-PGF1 alpha in both groups were determined in the fixed time points. RESULTS: The various parameters in the treated group were all better than those in the control group (P < 0.05 or P < 0.01), the occurrence rate of acute lung injury and its mortality in the treated group were 7.5% (3/40) and 0% (0/3) respectively, while in the control group were 19.4% (7/36) and 43% (3/7) respectively. CONCLUSION: CR has good preventive and treatment effect in treating complicated acute lung injury during extracorporeal circulation (cardiopulmonary bypass) in patients with pulmonary hypertension.

[Translocation of intestinal endotoxin and bacteria induced by the apoptosis of enterocytes in scald rats after delayed resuscitation].

OBJECTIVE: To investigate the role of enterocyte apoptosis in translocation of intestinal endotoxin and bacteria after delayed resuscitation in scalded rats. METHODS: One hundred and ten male Wistar rats were divided randomly into two groups: group A, early resuscitation, n=60; group B, delayed resuscitation, n=50. All animals were subjected to 30% total body surface area (TBSA) full-thickness scald. In group A, saline resuscitation was begun immediately after the injury. Saline resuscitation later than 6 hours after scalding was referred as delayed resuscitation. Apoptosis of enterocytes was identified by DNA fragmentation (ap%), DNA agarose gel electrophoresis, TdT-mediated dUTP nick end labeling (TUNEL) method and electron microscope (EM). The levels of endotoxin in portal vein and systemic circulation were determined by limulus amebocyte lysate technique. The amount of bacteria in mesenteric lymph nodes (MLN) was detected by a quantitative bacteria culture of biopsy. RESULTS: The ap% of enterocytes was increased significantly in groups A and B, peaking at 12 hours postburn. The increased ap% in the group B occurred much earlier and higher than in group A from 3 hours to 48 hours postburn (P<0.05 or P<0.01). This was corroborated by the results observed in electrophoresis, TUNEL method and EM. The portal endotoxin was much higher in group B than in group A at the same postburn timepoints. So were the endotoxin levels in systemic circulation. A significant positive relationship existed between the portal endotoxin levels and the ap% of intestinal epithelial cells in groups A and B (group A: r=0.936, P<0.01; group B: r=0.899, P<0.05). The frequency of bacteria translocation of MLN in group B was higher than that in group A. CONCLUSION: Significant pathologic apoptosis of enterocytes is induced by delayed resuscitation after thermal injury in rats. This may lead to a compromise of intestinal barrier. It may be one of the major causes of translocation of endotoxin and bacteria postburn.

[Study of diagnostic criteria of acute respiratory distress syndrome and multiple organ dysfunction syndrome at high altitude: revised draft of the diagnostic criteria of high acute respiratory distress syndrome drawn in Lanzhou conference].

OBJECTIVE: To compare the difference of the diagnostic parameters of acute respiratory distress syndrome/multiple organ dysfunction syndrome (ARDS/MODS) at high altitude (H-ARDS/MODS) with that on plains and reevaluate the practicality and feasibility of the diagnostic criteria of H-ARDS (Lanzhou conference, 1999). METHODS: Three hundred and sixty cases with relatively complete data were divided into three groups according to their originating altitude: control group on plains (CG, n=93), high altitude group 1 at the altitude of 1,517 m (H1G, n=223), high altitude group 2 at the altitude of 2,261-2,400 m (H2G, n=44). The ARDS/MODS scorings of the three groups were carried out according to the diagnostic criteria of Lushan Conference, Marshall (1995) and Lanzhou criteria drafted by the authors and the receiver operating characteristic curves (ROC curve) were made to predict the outcome of MODS. RESULTS: In CG group, the area of ROC, the susceptibility and specificity were 0.823, 0.833, 0.731, respectively according to Lushan criteria, which were better than those (0.815, 0.767, 0.763) according to Marshall criteria. Then in group H2G, the area of ROC, the susceptibility and specificity according to Lushan criteria were lower than those according to Marshall criteria: 0.855, 0.583, 0.969 vs 0.914, 1.000, 0.657. The optimum cutoff points of partial pressure of oxygen in artery (PaO(2))/fractional concentration of inspired oxygen (FiO(2)) were 198.32 mmHg, 131.50 mmHg and 97.58 mmHg in group CG, H1G and H2G. CONCLUSION: (1) There are significant differences between the diagnostic criteria of ARDS at high altitude and that on plains. The altitude of 1 517 m would be an important border line in diagnosing H-ARDS. (2) The drafted diagnostic criteria of ARDS at high altitude are feasible and practical in this region, but the range of the parameters is still wide, which need to be properly amended. (3) The changing tendency of the parameters of MODS at high altitude is different from that on plains, but the amount of sample needs to be accumulated further and the Lanzhou criteria needs to be perfected.

[Change in apoptosis rate and expression of apoptosis-related gene of lamina propria lymphocyte and intra-epithelial lymphocyte after burn and delayed resuscitation].

OBJECTIVE: To study the effects of delayed resuscitation on the apoptosis rate (ap%) and expression of apoptosis-related genes of lamina propria lymphocytes (LPL), intra-epithelial lymphocyte(IEL) after burn in rats. METHODS: Thirty Wistar rats were randomly divided into early resuscitation (ER) and delayed resuscitation (DR) groups, 24 rats of them were subjected to 30% total body surface area (TBSA) III degree scald burn on back, among which 12 received fluid resuscitation immediately, and 12 with delayed fluid resuscitation. Six rats were subjected to sham burn served as control. DNA fragmentation, DNA agarose gel electrophoresis were used to observe the apoptosis of LPL and IEL. Reverse transcription-polymerase chain reaction (RT-PCR) was employed to detect the expression of interleukin-1beta-converting enzyme (ICE) and B cell lymphoma-2 (bcl-2). RESULTS: The ap% of LPL and IEL increased significantly after burn (all P<0.01). The ap% in DR group was higher than in ER group at 12 hours postburn. Distinct DNA "ladders" were visualized in agarose gel electrophoresis 6 hours postburn for both LPL and IEL. The expression of ICE gene increased dramatically after burn, and it expressed higher in DR group than that in ER group postburn (P<0.05 or P<0.01). A strong expression of bcl-2 in LPL and IEL were detected before burn, but the expressions decreased significantly after burn and delayed resuscitation (P<0.05 or P<0.01). CONCLUSION: The apoptosis of LPL and IEL increased significantly after burn and delayed resuscitation. The unbalanced expression of apoptosis-enhanced gene ICE and apoptosis-inhibited gene bcl-2 may be responsible for the dramatically increased apoptosis of LPL and IEL postburn.