Gadolinium chloride prevents mortality in hepatectomized rats given endotoxin

The purpose of this study was to determine if inhibition of Kupffer cells by gadolinium chloride (GdCl(3)) affects the arterial ketone body ratio (AKBR), liver injury, and mortality in hepatectomized rats administered lipopolysaccharide (LPS). Rats treated with or without GdCl(3) received a 70% hepatectomy. Either LPS (5 mg/kg) or vehicle (saline) was administered 48 h after hepatectomy. Further, hepatectomized rats were administered superoxide dismutase (CuZnSOD, 9 x 10(4) U/kg) before and every 3 h after LPS injection up to 9 h to assess involvement of superoxide in liver injury in this model. All hepatectomized rats with saline died within 24 h after LPS administration. In contrast, GdCl(3) prevented this mortality completely. Serum AST levels were about 160 IU/L in hepatectomized rats with vehicle; however, values were increased approximately 25-fold by LPS administration. In contrast, these increases were blunted significantly by about 90% by GdCl(3). Further, GdCl(3) also prevented decreases in AKBR caused by LPS. LPS caused severe liver injury, which was stopped almost completely by GdCl(3). LPS-induced increases in superoxide production by isolated Kupffer cells were stopped by about 90% by GdCl(3). Importantly, SOD administration prevented decreases in AKBR, liver injury, and mortality significantly as well as GdCl(3). These results indicated that GdCl(3) prevented liver injury and mortality caused by LPS most likely by inhibiting superoxide production by Kupffer cells. Thus, inhibition of activation of Kupffer cells could be useful for preventing liver dysfunction in postoperative endotoxemia.     

Role of Kupffer cells in lung injury in rats administered endotoxin 1

The purpose of this study was to investigate the regulation of lung macrophages (Muvarphis) by Kupffer cells (KCs) in lung injury caused by endotoxemia. Phenotypic differences in tissue Muvarphis were also investigated. Muvarphis were isolated from gadolinium chloride (GdCl(3))- or saline-treated rats 2 h after saline or lipopolysaccharide (LPS) administration. Furthermore, rats were given GdCl(3) 24 h prior to LPS administration, and survival rate was assessed for 24 h. Moreover, lung edema was assessed 9 h after LPS injection. Expression of inflammatory mediators was measured in the liver and lung. KCs were divided into three subpopulations based on size and phagocytosis. The expression of TNF-alpha and MIP-2 was greater in the small KCs and lung Muvarphis, while the expression of IL-6, IL-10, and MCP-1 was greater in the large and intermediate KCs. GdCl(3) eliminated ED2-positive large KCs and did not have any effect on the lung Muvarphis. The number of ED1-positive KCs increased significantly in both organs after LPS challenge and was reduced by GdCl(3). The population of ED2-positive KCs did not change following LPS administration. GdCl(3) completely prevented increases in lung microvascular permeability and mortality after LPS infusion. After LPS administration, expression of TNF-alpha and IL-6 increased rapidly and then decreased gradually in both organs. GdCl(3) inhibited these increases in the liver significantly and enhanced the expression of MCP-1 and IL-10 in the lung 9 h after LPS administration. Thus, the heterogeneous response of KCs to endotoxin leads to production of certain cytokines and chemokines that affect lung function.     

Endogenous gut-derived bacterial endotoxin tonically primes pancreatic secretion of insulin in normal rats

This laboratory has proposed that endogenous gut-derived bacterial endotoxin primes the pancreatic secretion of insulin in normal rats. Endogenous lipopolysaccharide (LPS) is continually absorbed from the gut into intestinal capillaries, and low-grade portal venous endotoxemia is the status quo. Under physiologic conditions, Kupffer cells of the liver totally phagocytize and degrade endotoxin from the portal circulation. Evidence from this and other laboratories indicates that administration of exogenous LPS to humans and rats enhances pancreatic secretion of both insulin and glucagon. Conversely, findings of the present study demonstrate that restriction of endogenous LPS in fasted rats depresses the basal and arginine-stimulated concentrations of plasma insulin. Techniques used to restrict gut-derived LPS availability included chronic daily gavage with neomycin and cefazolin for gut sterilization and with cholestyramine or lactulose to reduce endotoxin within the gut. In addition, induction of endotoxin tolerance was produced by progressively higher doses of LPS intraperitoneally (i.p.), and polymyxin B was administered subcutaneously (s.c.) daily to neutralize the lipid A portion of circulating LPS. Finally, isolator-reared, defined flora rats, which were gram-negative-bacteria-deficient, and, therefore, LPS-deficient, were compared with conventional counterparts. Basal plasma insulin but not glucagon levels were consistently and significantly reduced in endogenous LPS-restricted animals. Glucose-stimulated plasma insulin was decreased only after parenteral treatment by tolerance induction and polymyxin B administration. Both plasma insulin and glucagon were depressed in response to arginine challenge in most LPS-restricted rats.(ABSTRACT TRUNCATED AT 250 WORDS)     

In vivo expression of lipopolysaccharide binding protein and its gene induced by endotoxin

To investigate the expression of lipopolysaccharide binding protein (LBP) and its gene inrats with endotoxemia and explore the role of LBP in the response of host to endotoxin.     

Protection of sinusoidal endothelial cells against storage/reperfusion injury by prostaglandin E2 derived from Kupffer cells.

BACKGROUND: In clinical liver transplants, grafts are frequently exposed to endotoxin (lipopolysaccharide, LPS) before harvest and may be predisposed to dysfunction. Because graft failure is linked to sinusoidal endothelial cell injury after storage/reperfusion, we investigated the effect of donor exposure to LPS on graft survival in relation to sinusoidal endothelial cell injury after storage/reperfusion in rats. METHODS: Rats were injected with 0.5 mg/kg LPS. In some rats, 20 mg/kg GdCl3 or 5 mg/kg indomethacin was injected before LPS to ablate Kupffer cells and inhibit prostaglandin (PG) synthesis, respectively. Other rats were injected with 100 microg/kg dimethyl PGE2, a stable PGE2 analog. Rat livers were harvested, stored in cold UW solution and transplanted to non-treated rats for determination of survival and liver injury in recipients. Otherwise, after cold storage, the livers were reperfused briefly with physiological buffer containing trypan blue for determination of sinusoidal endothelial cell injury by counting trypan blue-positive nuclei in histological sections. RESULTS: Donor treatment with LPS increased hepatic PGE2 production before storage and decreased recipient survival, but paradoxically decreased killing of sinusoidal endothelial cells after storage and reperfusion. Pretreatment of donors with GdCl3 or indomethacin prevented the protective preconditioning of sinusoidal endothelial cells by LPS, whereas pretreatment with dimethyl PGE2 protected sinusoidal endothelial cells to the same extent as LPS. Unlike LPS, however, PGE2 attenuated graft injury after liver transplants. CONCLUSION: PGE2 derived from LPS-stimulated Kupffer cells protects sinusoidal endothelial cells against storage/reperfusion injury. Unlike LPS, PGE2 improves graft function after liver transplants. Thus, donor preconditioning with PGE2 may be beneficial in liver transplants.     

Autonomic Nervous System and Gut-derived Endotoxin: Involvement in Activation of Kupffer Cells after In Situ Organ Manipulation

Gentle in situ organ manipulation rapidly causes disturbances in the hepatic microcirculation, hypoxia, and activation of Kupffer cells. Because the mechanisms of Kupffer cell activation after organ manipulation remain unclear, the possible role of the autonomic nervous system and gut-derived endotoxin were assessed. To mimic what occurs with major abdominal surgery, livers from female Sprague-Dawley rats (200–230 g) underwent minimal dissection for 12 minutes and were manipulated gently or were left alone for 13 subsequent minutes. Kupffer cells were activated 2 hours after manipulation, reflected by a significant increase in intracellular calcium ([Ca²⁺]_i) from about 90 nM in unmanipulated controls to more than 180 nM in response to lipopolysaccharide (LPS 100 ng/ml). Furthermore, Kupffer cells from manipulated rats produced about threefold more tumor necrosis factor-α after LPS (100 ng/ml) than did the unmanipulated controls. Moreover, O₂ uptake of ex situ perfused liver was increased from about 110 μmol/g/hr in unmanipulated controls to more than 160 μmol/g/hr 2 hours after organ manipulation. Binding of pimonidazole (120 mg/kg IV), a 2-nitroimidazole hypoxia marker given 2 hours after manipulation, increased about 2.5-fold, and hepatic glycogen was depleted. Two hours after organ manipulation gut permeability to horseradish peroxidase was elevated and endotoxin in the portal venous blood was increased twofold. Microsurgical hepatic denervation, ganglionic blockade, adrenalectomy, and antibiotics to sterilize the gut before manipulation prevented activation of Kupffer cells by organ manipulation. Hexamethonium and adrenalectomy prevented increases in gut permeability caused by manipulation. Although antibiotics blunted the increase in portal venous endotoxin significantly, there was no effect on gut permeability. These data indicate for the first time that both the autonomic nervous system and gut-derived endotoxin are involved in activation of Kupffer cells after organ manipulation.     

烧伤并发内毒素血症早期肝损害与TNF—αmRNA表达的实验研究

目的 观察TNF－αmRNA及其蛋白的组织分布和细胞定位,探讨烧伤并发内毒素血症早期肝损害的发生机理。方法 选用20％Ⅲ度TBSA烧伤大鼠合并腹腔内毒素（LPS）注射造成烧伤复合内毒素血症肝损害模型,采用光镜,电镜及免疫组化原位杂交染色观察产肝脏的形态功能变化、血清TNF－α含量变化、肝组织TNF－α和TNF－α mRNA的细胞定位及其分布。结果 烧伤复合内毒素血症组,光镜下主要表现肝窦反应,枯否细胞（KCs)激活与增生以及肝细胞（HCs)变性坏死等;电镜下主要表现肝窦内血小板聚集、纤维素沉积与中性粒细胞（PMNs)扣押以及KCs、肝细胞退变溶解等。血清丙氨酸氨基转氨酶（ALT）显著升高（P＜0．01）和白蛋白（ALB）轻度下降。组织TNF－α主要定位于肝窦内皮细胞（SECs)、KCs。TNF－αmRNA主要定位于KCs、PMNs、巨噬细胞（MPs)。而在单因素组主要特点为病变程度轻,肝功能损害不明显,血清TNF－α峰值滞后以及组织TNF－α和TNF－αmRNA表达相对较弱等。结论 TNF－α是参与烧伤复合内毒素血症早期肝脏损害的重要细胞因子。     

The role of intestinal flora on the interactions between nonparenchymal cells and hepatocytes in coculture

Kupffer cells are exposed directly to a number of factors in the portal circulation that can modify or regulate their responses to septic stimuli. The gut represents a potential source of a number of these factors including endotoxin, lymphokines, and prostaglandins. We examined Kupffer cells from germfree rats and germfree rats exposed to endotoxin or bacteria via their GI tracts to determine the importance of the intestinal flora in maintaining or modulating Kupffer cell responses. Kupffer cells from germfree animals were reduced in numbers and failed to respond to LPS in Kupffer cell: hepatocyte coculture. When germfree rats were exposed to bacterial endotoxin or bacteria via the gastrointestinal tract their Kupffer cells increased in numbers to normal and the cells responded to LPS in culture. Intestinal overgrowth with Escherichia coli for 2 days activated the Kupffer cells and significantly increased Kupffer cell sensitivity to LPS. These data suggest that the environment of the gastrointestinal tract is important for normal Kupffer cell responses and that intestinal bacterial overgrowth can modify Kupffer cell responses to septic stimuli.     

Countervailing influence of tumor necrosis factor-alpha and nitric oxide in endotoxemia

Tumor necrosis factor-alpha (TNF-alpha), a crucial mediator in sepsis, elicits multiple biologic effects, including intravascular thrombosis and circulatory shock. TNF-alpha exerts its biologic effects through two distinct cell surface receptors, TNF-R1 and TNF-R2. The pathophysiologic interaction between TNF-alpha and nitric oxide (NO) in glomerular thrombosis caused by endotoxemia in rats and wild-type mice (C57BL6) as well as in knockout mice that are deficient in TNF-R1 (R1 -/-), TNF-R2 (R2 -/-), or both receptors (R1R2 -/-) was studied. Administration of lipopolysaccharide (LPS; Escherichia coli endotoxin) resulted in increased NO and TNF-alpha production but failed to induce glomerular thrombosis. Concomitant administration of LPS + NG-nitro-L-arginine methyl ester (L-NAME; an NO synthesis inhibitor) resulted in glomerular thrombosis in rats and in wild-type mice. Intraperitoneal administration of pentoxifylline before LPS inhibited TNF-alpha synthesis and prevented glomerular thrombosis in rats given LPS + L-NAME. In contrast to the results observed in rats and wild-type mice, administration of LPS + L-NAME did not result in glomerular thrombosis in knockout mice with either single or double TNF-alpha receptor deletion. Thus, during endotoxemia, (1) TNF-alpha fosters glomerular thrombosis if there is deficiency of NO synthesis and (2) both TNF-alpha receptors are necessary for TNF-alpha's prothrombogenic action. Clinically, these novel studies suggest that in gram-negative endotoxemia, inhibition of NO synthesis and selective blockade of TNF-alpha receptors may provide unique therapeutic approaches for mitigation of glomerular thrombosis and restitution of vascular tone.     

内毒素血症时肝组织中脂多糖受体CD14的表达及其意义

目的 观测内毒素血症时大鼠肝组织中脂多糖受体CD14 mRNA的表达及其在内毒素介导Kupffer细胞（KCs)激活中的作用。方法 经大鼠尾静脉注入内毒素（剂量按5mg/kg计算）建立内毒素血症动物模型，测定血浆中内毒素、脂多糖结合蛋白（LBP)、TNF－α及IL－6含量变化，同时观测不同时相点肝组织中CD14 mRNA的表达及肝组织形态学变化，并与生理盐水组大鼠相比较。结果 在内毒素血症组大鼠中，随着血浆LPS浓度升高和时间延长，肝组织中CD14 mRNA的表达明显增强；血浆中LBP、TNF－α和IL－6含量也明显增加，与对照组相比较有显著差异（P＜0．01）。伴随KCs激活和肝细胞损伤的形态学改变，表现为KCs数量增多、体积增大、噬功能增强，肝细胞出现变性、坏死等变化。结论 内毒素血症时，随着肝组织中CD14表达增强和血浆LBP增加，可介导KCs激活，产生和释放多种细胞因子，诱导或加重肝组织及其它器官的损害。     

Regulation of pro-inflammatory and anti-inflammatory cytokine responses by Kupffer cells in endotoxin-enhanced reperfusion injury after total hepatic ischemia

The effects of Kupffer cells on cytokine responses in endotoxin-enhanced reperfusion injury after total hepatic ischemia were investigated in this study. Male rats pretreated with either normal saline solution (NS group) or gadolinium chloride (GdCl(3)) to inhibit Kupffer cell function (GC group) were subjected to 60 min of hepatic ischemia. These animals received either normal saline solution or sublethal doses of endotoxin (1 mg/kg) at reperfusion. In the NS group, endotoxin administration induced an enhanced tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 production 1 h after reperfusion with a subsequent peak of macrophage inflammatory protein-2 (MIP-2) levels, which resulted in a 7-day survival rate of 30%. Despite endotoxin administration, GdCl(3) pretreatment significantly suppressed TNF-alpha and increased interleukin-10 production 1 h after reperfusion, which led to a decline in MIP-2 production and amelioration of functional and structural liver damage with a 7-day survival rate of 80%. Augmented pro-inflammatory and anti-inflammatory cytokine responses by Kupffer cells were associated with endotoxin-enhanced reperfusion injury after hepatic ischemia. Kupffer cell blockade has a potential to attenuate the insult via modulation of cytokine responses.     

Protective effect of the intravenous administration of ursodeoxycholic acid against endotoxemia in rats with obstructive jaundice

This study was undertaken to elucidate the effect of the intravenous administration of ursodeoxycholic acid (UDCA) on endotoxemia in rats with obstructive jaundice from the viewpoint of the biliary excretion of lipopolysaccharide (LPS) through hepatocytes. In rats with obstructive jaundice, fluorescein isothiocyanate-labeled LPS was administered via the portal vein and then its biliary excretion was examined. A significant increase in the LPS excretion was thus noticed in UDCA-treated rats at a dose of 0.1μmol/100g body wt. per min. In place of UDCA, sodium taurocholate at the same dose also enhanced the biliary excretion of LPS. Secondly, we also examined whether or not UDCA protects against endotoxemia. In this experiment, nonlabeled LPS was administered via the portal vein and its peripheral concentration was then measured. In UDCA-treated rats, the endotoxin concentration was significantly lower. Finally, to elucidate the effect of UDCA on Kupffer cells, serum tumor necrosis factor (TNF-α) was measured. But UDCA had no effect on the TNF-α level. These findings thus demonstrate that the intravenous administration of UDCA protects against endotoxemia by enhancing the transport of LPS across the hepatocytes from blood to bile without affecting Kupffer cells, and that this biliary excretion of LPS is dependent on bile acids.     

联合应用甘氨酸和甲强龙对失血性休克大鼠肝脏枯否细胞的影响

目的探讨失血性休克大鼠肝脏枯否细胞的功能变化以及联合应用甘氨酸和甲强龙对枯否细胞的影响。方法50只大鼠随机分成假休克组（仅进行手术操作但不放血诱导休克）、休克组、甘氨酸组、甲强龙组和联合治疗组（甘氨酸＋甲强龙）,每组10只。大鼠经动脉放血,造成失血性休克,随后用自体血和生理盐水回输进行复苏。复苏后2h,行肝脏枯否细胞的分离和培养,细胞培养24h后分别用1、10、100和1000ng/ml的脂多糖（LPS）刺激,测定细胞内Ca^2＋和肿瘤坏死因子α（TNF-α）水平。结果枯否细胞内Ca^2＋在20min左右开始大幅度增高,大约27min达到高峰,同时细胞内Ca^2＋浓度增加呈现LPS剂量依赖性。联合治疗组细胞内Ca^2＋浓度和TNF-a含量明显低于休克组以及低于甘氨酸、甲强龙治疗组,差异具有统计学意义（P〈0．005）。结论联合应用甘氨酸和甲强龙比单一制剂更有效抑制失血性休克后枯否细胞内Ca^2＋升高、抑制枯否细胞的激活,抑制TNF-α的过度产生和机体炎症反应。     

Nonspecific phosphodiesterase inhibition attenuates liver injury in acute endotoxemia

BACKGROUND: Endotoxemia is accompanied by pro-inflammatory cytokine production, generation of reactive oxygen species, and end-organ injury. Pentoxifylline (PTX), a methylxanthine derivative and phosphodiesterase inhibitor, is known for its anti-inflammatory properties, including down-regulation of interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha synthesis. Its effects on liver function and hepatic histology following acute endotoxemia have not been investigated fully. We hypothesized that PTX would preserve liver architecture and function after intravenous lipopolysaccharide (LPS) injection. METHODS: Anesthetized Sprague-Dawley rats received an i.v. bolus injection of LPS (5 mg/kg), LPS + PTX (25 mg/kg), or saline (sham). Plasma concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), TNF-alpha, IL-6, and nitrite were measured at different time points after LPS injection. Liver injury was graded according to a scoring system in a blinded fashion from 0 (normal) to 4 (severe) for hepatocellular necrosis, hemorrhage, and parenchymal and sinusoidal inflammatory infiltrates. Neutrophil infiltration was measured by counting myeloperoxidase (MPO)-positive stained cells. Nuclear factor (NF)-kappaB p-65 was measured by counting positive stained nuclei of hepatocytes and Kupffer cells (KC). Inducible nitric oxide synthase (iNOS) was evaluated by positively stained KC. Data are presented as mean +/- SEM. Analysis of variance with p < 0.05 was considered statistically significant. RESULTS: Animals treated with PTX showed a significant reduction in liver injury score and neutrophil infiltration. Treatment with PTX significantly decreased TNF-alpha, IL-6, and the concentrations of AST and ALT when compared to LPS alone. In addition, a significant decrease in NF-kappaB-positive staining in hepatocytes and KC, as well as in KC iNOS immunostaining was observed in PTX-treated animals compared to the LPS group. CONCLUSIONS: Pentoxifylline downregulates the inflammatory response significantly and decreases liver injury in acute endotoxemia.     

Functional heterogeneity of the kupffer cell population is involved in the mechanism of gadolinium chloride in rats administered endotoxin

BACKGROUND: The purpose of this study was to determine if evidence of functional heterogeneity between subtypes of the Kupffer cell (KC) may be involved in the mechanism of the protective effect of gadolinium chloride (GdCl3) in endotoxemia. METHODS: Rats pretreated with or without GdCl3 were administered lipopolysaccharide (LPS) or vehicle. Serum and liver tissues were collected after LPS administration for cytokine measurements and pathological and immunohistochemical evaluation. RESULTS: After LPS administration, increases in expression of TNF-alpha and IL-6 mRNA in the liver were blunted significantly by GdCl3. In control liver tissue, ED2-positive cells were a predominant fraction, with a few ED1-positive cells, and GdCl3 eliminated only ED2-positive cells. Further, ED2-positive cells were larger in size than ED1-positive ones. Importantly, the number of ED1-positive cells in the liver was increased about threefold in the control group but not in the GdCl3 group after LPS injection. Intermediate or large KCs isolated by counterflow centrifugal elutriation showed greater capacity for phagocytosis and production of superoxide and TNF-alpha than small ones. In contrast, IL-6 production was increased to a greater extent in small than in intermediate or large cells. GdCl3 eliminated the intermediate or large KC subpopulation predominantly. CONCLUSION: Collectively, functional heterogeneity of the KC population was involved in the mechanism of the protective effects of GdCl3 in endotoxemia. TNF-alpha derived from activated intermediate or large KCs may activate small KCs and the latter may be recruited to other organs, such as lungs and kidneys, and produce a large amount of IL-6, leading to multiple organ failure.     

Endotoxin-induced liver injury after extended hepatectomy and the role of kupffer cells in the rat

Liver injury by endotoxin given during regeneration following a 70% hepatectomy was examined in Wistar rats. The intravenous administration of endotoxin caused an elevation of the serum GPT level, and severe damage of the remnant liver showing centrilobular necrosis with microthrombi. The highest mortality was induced by the administration of endotoxin to rats 24h after hepatectomy. Kupffer cells in the regenerative phase of the liver showed an augmented in vitro production of both tumor necrosis factor (TNF) and interleukin-1 (IL-1). The simultaneous administration of heparin and prostagladin E₁ (PGE₁), which is known to suppress the production of TNF and IL-1, reduced the magnitude of liver injury and the mortality of these rats. The absence of any direct cytotoxic effect of TNF and IL-1 against liver cells suggested that the cytokines, produced by Kupffer cells, play an important but indirect role in the remnant liver injury induced by endotoxin after hepatectomy.     

Intestinal gram-negative bacterial overgrowth in vivo augments the in vitro response of Kupffer cells to endotoxin.

A number of disease states and therapeutic maneuvers common to surgical patients can result in changes in the intestinal flora, permitting bacterial overgrowth and translocation of bacteria to gut lymphoid tissue. It is possible that these changes in gut flora increase portal levels of several factors that are capable of altering macrophage activation state, including endotoxin, lymphokines, and eicosanoids. Since Kupffer cells are directly exposed to gut factors via the portal circulation, changes in intestinal flora may influence Kupffer cell responses. Using germfree rats, it has previously been shown that the presence of gut bacterial flora is important in inducing Kupffer cells to respond to endotoxin, and that an overgrowth of gram-negative bacteria can further augment Kupffer cell responses, supporting the above-mentioned hypothesis. The current set of experiments examines how intestinal gram-negative bacterial overgrowth in normal adult rats effects the response of Kupffer cells to septic stimuli. Kupffer cells were obtained from conventional rats with induced intestinal overgrowth with Escherichia coli C25 for 2 or 7 days. After 2 days of overgrowth, Kupffer cells were only slightly less responsive to lipopolysaccharide (LPS) than control Kupffer cells. However, after 7 days of overgrowth, when placed in coculture with normal hepatocytes, Kupffer cells were significantly more responsive to LPS (p less than 0.001), inducing a greater degree of suppression in hepatocyte protein synthesis at lower LPS concentrations. When cultured alone, Kupffer cells from these animals also produced more interleukin-1 (p less than 0.002) and prostaglandin E2 (PGE2) (p less than 0.009) in response to LPS. These results show that intestinal gram-negative bacterial overgrowth in conventional rats can have direct influences on the response of hepatic macrophages to septic stimuli, and provides further support to the hypothesis that imbalances in the intestinal flora can effect the responses of immune cells in other sites of the body.     

烫伤大鼠组织肿瘤坏死因子mRNA表达与内毒素血症的关系

目的 探讨烫伤后不同组织肿瘤坏死因子（ＴＮＦ－α）ｍＲＮＡ的动态表达及其与内毒素血症的关系。方法 采用大鼠３５％体表面积Ⅲ度烫伤模型,实验随机分为正常对照组、烫伤组、多粘菌素Ｂ治疗组。血浆内毒素水平采用改良过氯酸预处理血浆偶氮显色法鲎试验定量测定;组织ＴＮＦ－αｍＲＮＡ含量采用逆转录聚合酶链反应检测。结果 烫伤后门静脉及体循环内毒素水平均显著升高,８ｈ达高峰,２４ｈ则逐渐下降。给予低剂量多粘菌素Ｂ     

阻塞性黄疸患者肝脏巨噬细胞功能变化的临床研究

为探讨阻塞性黄疸患者围手术期感染发生率明显增高的原因，对３６例阻塞性黄疸患者围手术期肝脏Ｋｕｐｆｆｅｒ细胞吞噬功能和血浆内毒素水平变化进行了观察，并与２０例单纯性胆囊结石患者进行比较。结果显示：胆道梗阻后Ｋｕｐｆｅｒ细胞吞噬功能降低，与对照组比较有显著性差异（Ｐ＜０．０５）；血浆内毒素含量升高，与对照组比较有高度显著性差异（Ｐ＜０．０１）。经手术胆道引流后，血浆内毒素水平则逐渐降低。随着Ｋｕｐｆｅｒ细胞吞噬功能恢复，血浆内毒素进一步降低。由此表明，胆道梗阻后Ｋｕｐｆｅｒ细胞吞噬功能变化与血浆内毒素水平有显著的相关关系。     

An ultrastructural study of the changes of the liver and spleen induced by experimental E. coli endotoxin shock--with special reference to effects of the low-dose heparin therapy

Firstly, the author has investigated how low-dose heparin had influence on reticuloendothelial system of the normal Wistar rats. Secondly, the effect of the low-dose heparin therapy on E. coli endotoxin shock was investigated as to the ultrastructural changes of the liver and spleen of rats. Activation of the phagocytosis which was substantiated by increased uptake of the carbon was observed in heparin administered rats. In this group, abundant development of intra-cellular organellae was noted in the cytoplasm of the hepatic Kupffer cells, macrophages and reticulum cells of the spleen. The E.coli endotoxin administration resulted in formation of micro-thrombi in sinusoidal spaces of the liver at 4 hours after administration. The Kupffer cells also involved in striking disintegration and necrosis. Similarly the sinusoidal lining cells were denudated with disintegration and necrosis. The above-mentioned changes persisted for long term, while the changes less in heparin administered group. The active phagocytic process was discernible in the latter group. Cellular preservation was also excellent in the spleen. The mortality was lower in initial heparin-treated group in comparison with that of untreated control group.