Influence of IFNα-2b and BCG on the release of TNF and IL-1 by Kupffer cells in rats with hepatoma

Graft Expression of p38 and Tumor Necrosis Factor-α in Heart Transplantation in Rats

Objectives

To investigate the expression of p38 mitogen-activated protein kinase and its relationship with myocardial apoptosis and tumor necrosis factor-α during acute cardiac allograft rejection and to study the effects of tacrolimus on the expression of the kinase.

Methods

Rats were divided into 3 groups: isograft (Lewis heart to Lewis rat; control group), allograft (Brown Norway heart to Lewis rat), and tacrolimus-treated allograft (Brown Norway heart to tacrolimus-treated Lewis rat). Grafts were collected 1, 3, 5, and 7 days after transplantation for determination of histopathological features, apoptosis of cardiac cells (by terminal deoxynucleotidyl transferase–mediated dUTP-biotin nick labeling), number of cells positive for both p38 and CD8 (by laser scanning confocal imaging), and expression of the kinase (by Western immunoblotting) and tumor necrosis factor-α (by reverse-transcriptase polymerase chain reaction).

Results

Compared with isografts from the control group, grafts from the untreated allograft group had significantly more apoptotic cells, greater expression of tumor necrosis factor-α and p38 mitogen-activated protein kinase, and more CD8-p38 double-positive cells at 5 and 7 days ( P<.05). The increases were prevented by treatment with tacrolimus.

Conclusions

The findings that the number of apoptotic cells, the number of CD8-p38 double-positive cells, the expression of tumor necrosis factor-α and p38 mitogen-activated protein kinase all increased during the same period in the allografts in nonimmunosuppressed recipients suggests that intragraft expression of p38 would be associated with the rejection in acute cardiac allograft rejection. Tacrolimus may alleviate rejection partly by inhibiting p38 mitogen-activated protein kinase.

Role of paroxetine in interferon-alpha-induced immune and behavioural changes in male Wistar rats

Treatment with pro-inflammatory cytokine, IFNalpha was documented to result in neuropsychiatric complications including depression and treatment with antidepressant, paroxetine could improve the depressive symptoms. Therefore, the effects of IFNalpha on behaviour and cytokine changes in the whole blood culture and in the prefrontal cortex, hypothalamus and hippocampus areas of the brain in wistar rats were investigated with emphasis on the role of paroxetine in the prevention of depressive behaviour induced by pro-inflammatory cytokines. The group of rats treated with IFNalpha (s.c. 50,000 IU/kg for 3 days/week for 5 weeks) was compared with three other groups; 1) saline control group (s.c. normal saline 0.2 ml/kg/day for 7 weeks), 2) paroxetine control group (paroxetine suspension orally 10 mg/kg/day for 7 weeks) and 3) group treated with paroxetine for 2 weeks followed by IFNalpha for 5 weeks. In open filed, the IFNalpha treated rats showed anxiety behaviour compared to the rats from the other groups. There was no significant difference in home cage emergence test, Morris water maze and object recognition test. There is no significant difference in plasma corticosterone between groups. The pro-inflammatory cytokines (TNFalpha, IL1beta and IFNgamma), were significantly higher whereas the anti-inflammatory cytokine, IL10 was lower in the stimulated whole blood culture of IFNalpha treated rats. In the brain, both pro-inflammatory cytokine IL1beta and anti-inflammatory cytokine IL10 were higher in hypothalamus of the IFNalpha treated rats; by contrast the concentration of IL10 was lowest in hippocampus region of this group compared to the other groups. The paroxetine pretreated rats did not show these cytokine changes following IFNalpha treatment. Thus it appears that paroxetine pretreatment prevents the pro-inflammatory changes in blood and brain following IFNalpha treatment in turn prevents the anxiety behaviour.

Interferon alpha induction of metallothionein in rat liver is not linked to interleukin-1, interleukin-6, or tumor necrosis factor alpha

Synthesis of metallothionein (MT) is induced by interferon-alpha (IFN-alpha) in vitro and in vivo. In addition, IFN-alpha promotes redistribution of zinc (Zn) from the plasma to the liver in mice. However, it is not clear if IFN-alpha induces hepatic MT synthesis directly or indirectly via liberation of other cytokines. In order to address this issue, we determined hepatic MT levels, Zn concentration in plasma, liver, and urine, and plasma levels interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNFalpha) in rats following intramuscular injection of human IFN-alpha (1.5 x 10(6) UI/m(2)). Animals were housed in metabolic cages and sacrificed at various times after IFN-alpha administration. Zn concentrations in serum, urine, and hepatic tissue were determined by atomic absorption spectrophotometry. MT protein was measured using the MT silver saturation method and expression of MT-1 and MT-2 mRNA was measured by RT-PCR. Plasma levels of rat IL-1, IL-6, and TNFalpha were determined using an ELISA method. Hepatic MT levels began to increase at 2 h following IFN-alpha administration and reached maximum levels at 12 h post-treatment. Induction of MT gene expression was confirmed by increases in MT-1 and MT-2 mRNA levels 6, 12, and 18 h after IFN-alpha administration. IFN-alpha treatment also resulted in biphasic increases in hepatic Zn, with levels peaking at 2 h, the time-point when MT levels are first increased, and again at 18 h. Concurrently, there were decreases in serum Zn levels at these time points, suggesting IFN-alpha induced movement of Zn from the blood to hepatic tissue. The decrease in serum Zn was not due to increased excretion since urinary Zn levels were unaffected following IFN-alpha treatment. IFN-alpha administration had no effect on plasma IL-1, IL-6, and TNFalpha levels. These results show that IFN-alpha promotes the increase of hepatic MT levels and plasma/liver redistribution directly, without IL-1, IL-6, or TNFalpha participation.

Synthesis of endotoxin receptor CD14 protein in Kupffer cells and its role in alcohol-induced liver disease

AIM: To observe the synthesis of endotoxin receptor CD14 protein and its mRNA expression in Kupffer cells (KCs), and evaluate the role of CD14 in the pathogenesis of liver injury in rats with alcohol-induced liver disease (ALD).

METHODS: Twenty-eight Wistar rats were divided into two groups: ethanol-fed group and control group. Ethanol-fed group was fed ethanol (dose of 5-12g·kg·d^-1) and control group received dextrose instead of ethanol. Two groups were sacrificed at 4 wk and 8 wk, respectively. KCs were isolated and the synthesis of CD14 protein and its mRNA expression in KCs were determined by flow cytometric analysis (FCM) or the reverse transcription polymerase chain reaction (RT-PCR) analysis. The levels of plasma endotoxin and alanine transaminase (ALT) were measured by Limulus Amebocyte Lysate assay and standard enzymatic procedures respectively, and the levels of plasma tumor necosis factor (TNF)-α and interleukin (IL)-6 were both determined by ELISA. The liver pathology change was observed under light and electric microscopy.

RESULTS: In ethanol-fed group, the percentages of FITC-CD14 positive cells were 76.23% and 89.42% at 4 wk and 8 wk, respectively. Compared with control group (4.45% and 5.38%), the difference was significant (P < 0.05). The expressions of CD14 mRNA were 7.56 ± 1.02 and 8.74 ± 1.37 at 4 wk and 8 wk, respectively, which were significantly higher compared with the control group (1.77 ± 0.21 and 1.98 ± 0.23) (P < 0.05). Plasma endotoxin levels at 4 wk and 8 wk increased significantly in ethanol-fed group (129 ± 21 ng·L^-1 and 187 ± 35 ng·L^-1) than those in control rats (48 ± 9 ng·L^-1 and 53 ± 11 ng·L^-1)(P < 0.05). Mean values of plasma ALT levels increased dramatically in ethanol-fed rats (112 ± 15 IU/L and 147 ± 22 IU/L) than those in the control animals (31 ± 12 IU/L and 33 ± 9 IU/L) (P < 0.05). In ethanol-fed rats, the levels of TNF-α were 326 ± 42 ng·L^-1 and 402 ± 51 ng·l^-1 at 4 wk and 8 wk, respectively which were significantly higher than those in control group (86 ± 12 ng·L^-1 and 97 ± 13 ng·L^-1) (P < 0.05). The levels of IL-6 were 387 ± 46 ng·L^{- 1} and 413 ± 51 ng·L^-1, which were also higher than control group (78 ± 11 ng·L^-1 and 73 ± 10 ng·L^-1) (P < 0.05). In liver section from ethanol-fed rats, there were marked pathological changes including steatosis, cell infiltration and necrosis. No marked pathological changes were seen in control group.

CONCLUSION: Ethanol administration led to a significant synthesis of endotoxin receptor CD14 protein and its gene expression in KCs, which maybe result in the pathological changes of liver tissue and hepatic functional damages.

Role of NF-κB in multiple organ dysfunction during acute obstructive cholangitis

AIM: To elucidate the role of NF-κB activation in the development of multiple organ dysfunction (MOD) during acute obstructive cholangitis (AOC) in rats.

METHODS: Forty-two Wistar rats were divided into three groups: the AOC group, the group of bile duct ligation (BDL group), and the sham operation group (SO group). All the animals in the three groups were killed in the 6th and 48th hour after operation. Morphological changes of vital organs were observed under light and electron microscopy. NF-κB activation was determined with Electrophoretic Mobility Shift Assay (EMSA). Arterial blood gas analyses and the serum levels of lactate dehydrogenase (LDH), alanine aminotransferase (ALT), blood urea nitrogen (BUN) and creatinine were performed. The concentrations of TNF-α and IL-6 in plasma were also measured.

RESULTS: The significant changes of histology and ultrastructure of vital organs were observed in AOC group. By contrast, in BDL group, all the features of organs damage were greatly reduced. Expression of NF-κB activation in various tissues increased in AOC group when compared to other two groups. At 6 h, the arterial pH in three groups was 7.52 ± 0.01, 7.46 ± 0.02, and 7.45 ± 0.02, and the blood pCO₂ was 33.9 ± 0.95 mmHg, 38.1 ± 0.89 mmHg, 38.9 ± 0.94 mmHg, there was difference in three groups (P < 0.05). At 48 h, the blood pHvalues in three groups was 7.33 ± 0.07, 7.67 ± 0.04, and 7.46 ± 0.03, and blood HCO₃^- was 20.1 ± 1.29 mmol·L^-1, 26.7 ± 1.45 mmol·L^-1 and 27.4 ± 0.35 mmol·L^-1, there was also difference in three groups (P < 0.05). In AOC group, Levels of LDH, ALT, BUN and creatinine were 16359.9 ± 2278.8 nkat·L^-1, 5796.2 ± 941.9 nkat·L^-1, 55.7 ± 15.3 mg/dl, and 0.72 ± 0.06 mg/dl, which were higher than in SO group (3739.1 ± 570.1 nkat·L^-1, 288.4 ± 71.7 nkat·L^-1, 12.5 ± 2.14 mg/dl, and 0.47 ± 0.03 mg/dl) (P < 0.05). Levels of plasma TNF-α and IL-6 in AOC at 48 h were 429 ± 56.62 ng·L^-1 and 562 ± 57 ng·L^-1, which increased greatly when compared to BDL group (139 ± 16 ng·L^-1, 227 ± 43 ng·L^-1) and SO group (74 ± 10 ng·L^-1, 113 ± 19 ng·L^-1) (P < 0.05).

CONCLUSION: The pathological damages and the NF-κB activation of many vital organs exised during AOC. These findings have an important implication for the role of NF-κB activation in MOD during AOC.

Graft expression of p38 and tumor necrosis factor-alpha in heart transplantation in rats

OBJECTIVES

To investigate the expression of p38 mitogen-activated protein kinase and its relationship with myocardial apoptosis and tumor necrosis factor-alpha during acute cardiac allograft rejection and to study the effects of tacrolimus on the expression of the kinase.

METHODS

Rats were divided into 3 groups: isograft (Lewis heart to Lewis rat; control group), allograft (Brown Norway heart to Lewis rat), and tacrolimus-treated allograft (Brown Norway heart to tacrolimus-treated Lewis rat). Grafts were collected 1, 3, 5, and 7 days after transplantation for determination of histopathological features, apoptosis of cardiac cells (by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick labeling), number of cells positive for both p38 and CD8 (by laser scanning confocal imaging), and expression of the kinase (by Western immunoblotting) and tumor necrosis factor-alpha (by reverse-transcriptase polymerase chain reaction).

RESULTS

Compared with isografts from the control group, grafts from the untreated allograft group had significantly more apoptotic cells, greater expression of tumor necrosis factor-alpha and p38 mitogen-activated protein kinase, and more CD8-p38 double-positive cells at 5 and 7 days (P < .05). The increases were prevented by treatment with tacrolimus.

CONCLUSIONS

The findings that the number of apoptotic cells, the number of CD8-p38 double-positive cells, the expression of tumor necrosis factor-alpha and p38 mitogen-activated protein kinase all increased during the same period in the allografts in nonimmunosuppressed recipients suggests that intragraft expression of p38 would be associated with the rejection in acute cardiac allograft rejection. Tacrolimus may alleviate rejection partly by inhibiting p38 mitogen-activated protein kinase.

Intestinal damage mediated by Kupffer cells in rats with endotoxemia

AIM: To determine the in vivo effects of phagocytic blockade of Kupffer cell (KC) on the release of proinflammatory cytokines in small intestinal lesion and on the integrity of intestinal tract by using gadolinium chloride (GdCl₃) during early endotoxemia.

METHODS: Wistar rats were divided into three groups: Group A, rats were injected with endotoxin (E. coli O111:B4, a dose of 12 mg•kg⁻¹) only; Group B, rats were pretreated intravenously with 25 mg of GdCl₃ per kg 24 h are given endotoxin; and Group C, sham operation only. All animals were sacrificed 4 h after endotoxin injection. In portion of the rats of three groups, bile duct was cannulated, which the bile was collected externally. Morphological changes of ileum were observed under light microscopy and electronic microscopy. The KC were isolated from rats by collagenase perfusion and in KC, expression of TNF-α and IL-6 mRNA were determined by RT-PCR analysis. Plasma and bile TNF-α and IL-6 Levels were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS: In group A, there were neutrophil infiltration and superficial epithelial necrosis of the ileal villi, sloughing of mucosal epithelium, and disappearance of some villi. In group B, the ileal mucosal damage was much reduced. Which in group C, no significant morphological changes were seen. GdCl₃ pretreatment decreased significantly the expression of TNF-α and IL-6 mRNA in group B (4.32 ± 0.47 and 4.05 ± 0.43) when compared to group A (9.46 ± 1.21 and 9.04 ± 1.09) (P < 0.05). There was no significant expression of TNF-α and IL-6 mRNA in group C (1.03 ± 0.14 and 10.4 ± 0.13). In rats of group A, the levels of TNF-α and IL-6 in bile and plasma were 207 ± 29 ng·L^-1, 1032 ± 107 ng·L^-1, 213 ± 33 ng·L^-1, and 1185 ± 127 ng·L^-1, respectively. In group B, they were 113 ± 18 ng·L^-1, 521 ± 76 ng·L^-1, 147 ± 22 ng·L^-1, and 572 ± 54 ng·L^-1, respectively. In group C, they were 67 ± 10 ng·L^-1, 72 ± 13 ng·L^-1, 109 ± 18 ng·L^-1, and 118 ± 22 ng·L^-1 respectively. There were significant difference between the three group (P < 0.05).

CONCLUSION: KC release cytokines TNF-α and IL-6 causing damage to the integrity of intestinal epithelium and play a crucial role in the initiation and progression of intestinal mucosal damage during early endotoxemia.

Hepatoprotective role of ganoderma lucidum polysaccharide against BCG-induced immune liver injury in mice

AIM: To examine the effect of ganoderma lucidum polysaccharide (GLP) on the immune liver injury induced by BCG infection, and investigate the relationship between degrees of hepatic damage and NO production in mice.

METHODS: Immune hepatic injury was markedly induced by BCG-pretreatment (125 mg·kg^-1, 2-week, iv) or by BCG-pretreatment plus lipopolysaccharide (LPS, 125 μg·kg^-1, 12-hour, iv) in mice in vivo. Hepatocellular damage induced by BCG-pretreated plus inflammatory cytokines mixture (CM), which was included TNF-α, IL-1β, IFN-γ and LPS in culture medium in vitro. Administration of GLP was performed by oral or incubating with culture medium at immune stimuli simultaneity. Liver damage was determined by activity of alanine aminotransferase (ALT) in serum and in hepatocytes cultured supernatant, by liver weight changes and histopathological examination. NO production in the cultured supernatant was determined by the Griess reaction. Moreover, inducible nitric oxide synthase (iNOS) protein expression was also examinated by immunohistochemical method.

RESULTS: Immune hepatic injury was markedly induced by BCG or BCG plus inflammatory cytokines in BALB/c mice in vivo and in vitro. Under BCG-stimulated condition, augment of the liver weight and increase of the serum/supernatant ALT level were observed, as well as granuloma forming and inflammatory cells soakage were observed by microscopic analysis within liver tissues. Moreover, NO production was also increased by BCG or/and CM stimuli in the culture supernatant, and a lot of iNOS positive staining was observed in BCG-prestimulated hepatic sections. Application of GLP significantly mitigated hepatic tumefaction, decreased ALT enzyme release and NO production in serum/supernatant, improved the pathological changes of chronic and acute inflammation induced by BCG-stimuli in mice. Moreover, the immunohistochemical result showed that GLP inhibited iNOS protein expression in BCG-immune hepatic damage model.

CONCLUSION: The present study indicates that NO participates in immune liver injury induced by Mycobacterium bovis BCG infection. The mechanisms of protective roles by GLP for BCG-induced immune liver injury may be due to influence NO production in mice.

Nuclear factor κB activity in patients with acute severe cholangitis

AIM: To determine the NF-κB activity in peripheral blood mononuclear cells (PBMC) in patients with acute cholangitis of severe type (ACST) and correlate the degree of NF-κB activation with severity of biliary tract infection and clinical outcome.

METHODS: Twenty patients with ACST were divided into survivor group (13 cases) and nonsurvivor group (7 cases). Other ten patients undergoing elective gastrectomy or inguinal hernia repair were selected as control group. Peripheral blood samples were taken 24 h postoperatively. PBMC were separated by density gradient centrifugation, then nuclear proteins were isolated from PBMC, and Electrophoretic Mobility Shift Assay (EMSA) used determined. The results were quantified by scanning densitometer of a Bio-Image Analysis System and expressed as relative optical density (ROD). The levels of TNF-α, IL-6, and IL-10 in the plasma of patients with ACST and healthy control subjects were determined by using an enzyme-linked immunoassay (ELISA).

RESULTS: The NF-κB activity was 5.02 ± 1.03 in nonsurvivor group, 2.98 ± 0.51 in survivor group and 1.06 ± 0.34 in control group. There were statistical differences in three groups (P < 0.05). The levels of TNF-α and IL-6 in plasma were (498 ± 53) ng·L^-1 and (587 ± 64) ng·L^-1 in nonsurvivor group, (284 ± 32) ng·L^-1 and (318 ± 49) ng·L^-1 in survivor group and (89 ± 11) ng·L^-1 and (102 ± 13) ng·L^-1 in control group. All patients with ACST had increased levels of TNF-α and IL-6, which were manyfold greater than those of control group, and there was an evidence of significantly higher levels in those of nonsurvivor group than that in survivor group (P < 0.05). The levels of IL-10 in plasma were (378 ± 32) ng·L^-1, (384 ± 37) ng·L^-1 and (68 ± 11) ng·L^-1 in three groups, respectively. All patients had also increased levels of IL-10 when compared with control group (P < 0.05), but the IL-10 levels were not significantly higher in nonsurvivors than in survivors (P > 0.05).

CONCLUSION: NF-κB activity in PBMC in patients with ACST increases markedly and the degree of NF-κB activation is correlated with severity of biliary tract infection and clinical outcome.

Liver sinusoidal endothelial cell injury by neutrophils in rats with acute obstructive cholangitis

AIM: The objective of this study is to elucidate the potential role of poly-morphonuclear neutrophils (PMN) in the development of such a sinusoidal endothelial cell (SEC) injury during early acute obstructive cholangitis (AOC) in rats.

METHODS: Twenty one Wistar rats were divided into three groups: the AOC group, the bile duct ligated group (BDL group), and the sham operation group (SO group). The common bile duct (CBD) of rats in AOC group was dually ligated and 0.2 mL of the E. coli O₁₁₁ B₄ (5 × 10⁹ cfu/mL) suspension was injected into the upper segment, in BDL group, only the CBD was ligated and in SO group, neither injection of E. coli suspension nor CBD ligation was done, but the same operative procedure. Such group consisted of seven rats, all animals were killed 6 h after the operation. Morphological changes of the liver were observed under light and electron microscope. Expression of intercellular adhesion molecule-1 (ICAM-1) mRNA in hepatic tissue was determined with reverse transcription polymerase chain reaction (RT-PCR). The serum levels of alanine aminotransferase (ALT) were determined with anutoanalyger and cytokine-induced neutrophil chemoattractant (CINC) was determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS: Neutrophils was accumulated in the hepatic sinusoids and sinusoidal endothelial cell injury existed in AOC group. In contrast, in rats of BDL group, all the features of SEC damage were greatly reduced. Expression of ICAM-1 mRNA in hepatic tissue in three groups were 7.54 ± 0.82, 2.87 ± 0.34, and 1.01 ± 0.12, respectively. There were significant differences among three groups (P < 0.05). The serum CINC levels in the three groups were 188 ± 21 ng•L⁻¹, 94 ± 11 ng•L⁻¹, and 57 ± 8 ng•L⁻¹, respectively. There were also significant differences among the three groups (P < 0.05). Activity of the serum ALT was 917 ± 167 nkat•L⁻¹, 901 ± 171 nkat•L⁻¹, and 908 ± 164 nkat•L⁻¹, respectively, (P > 0.05).

CONCLUSION: Hepatic SEC injury occurs earlier than hepatic parenchymal cells during AOC. Recruitments of circulating neutrophils in the hepatic sinusoidal space might mediate the SEC injury, and ICAM-1 in the liver may modulate the PMN of accumulation.

CCK8 inhibits expression of TNF-α in the spleen of endotoxic shock rats and signal transduction mechanism of p38 MAPK

AIM: To study the effect of sulfated cholecystokinin-octapeptide (CCK-8) on systemic hypotension, gene and protein expression of TNF-α in spleen of lipopolysaccharide (LPS) nduced endotoxic shock (ES) rats, and further investigate the signal transduction mechanism of p38 mitogen-activated protein kinase (MAPK).

METHODS: The changes of blood pressure were observed using physiological record instrument in four groups of rats: LPS (8 mg·kg^{- 1}, iv), CCK-8 (40 μg·kg^-1, iv) pretreatment 10 min before LPS (8 mg·kg^-1), CCK-8 (40 μg·kg^-1, iv) or normal saline (control) group. The content of TNF-α in the spleen was assayed 2 h after LPS administration using ELISA kit and the expression of TNF-α mRNA was examined 30 min, 2 h and 6 h after LPS administration by reverse transcribed polymerase chain reaction (RT-PCR). Activation of p38 MAPK was detected with Western blot 30 min after LPS administration.

RESULTS: CCK-8 reversed LPS-induced decrease of mean arterial pressure ( MAP ) in rats. The content of TNF-α in the spleen was (282 ± 30) ng·L^-1 in control group, while it increased to (941 ± 149) ng·L^-1 in LPS group, P < 0.01. CCK-8 significantly inhibited the LPS-induced increase of TNF-α content in spleen. It decreased to (462 ± 87) ng·L^-1 in CCK-8 + LPS group, P < 0.01. The expression of TNF-α mRNA 30 min and 2 h after treatment was stronger in LPS group, while it was lowered after CCK-8 pretreatment.The p38 MAPK expression increased significantly in LPS group (5.84 times of control) and CCK-8 increased the activation of p38 MAPK in ES rats (10.74 times of control).

CONCLUSION: CCK-8 reverses the decrease of MAP in ES rats and has inhibitory effect on the gene and protein expression of TNF-α in spleen, and p38 MAPK may be involved in its signal transduction mechanisms.

Effect of cholecystokinin on cytokines during endotoxic shock in rats

AIM: To study the effect of cholecystokinin-octapeptide (CCK-8) on systemic hypotension and cytokine production in lipopolysaccharide (LPS)-induced endotoxic shock (ES) rats.

METHODS: The changes of blood pressure were observed using physiological record instrument in four groups of rats: LPS (8 mg•kg¯¹, iv) induced ES; CCK-8 (40 μg•kg¯¹, iv) pretreatment 10 min before LPS (8 mg•kg¯¹); CCK-8 (40 μg•kg¯¹, iv) or normal saline (control) groups. Differences in tissue and circulating specificity of the proinflammatory cytokines (TNF-α, IL-1β and IL-6) were assayed with ELISA kits.

RESULTS: CCK-8 reversed LPS-induced decrease of mean artery blood pressure (MABP) in rats. Compared with control, LPS elevated the serum level of IL-6 significantly (3567 ± 687) ng•L¯¹vs 128 ± 22 ng•L¯¹, P < 0.01), while contents of TNF-αβ elevated significantly (277 ± 86 ng•L¯¹vs not detectable and 43 ± 9 ng•L¯¹vs not detectable, P < 0.01) but less extent than IL-6. CCK-8 significantly inhibited the LPS-induced increase in serum TNF-α, IL-1β and IL-6. LPS elevated spleen and lung content of IL-1β significantly (5184 ± 85 ng•L¯¹vs 1047 ± 21 ng•L¯¹ and 4050 ± 614 ng•L¯¹vs not detectable, P < 0.01), while levels of TNF-α and IL-6 also rose significantly but in less extent than IL-1β. CCK-8 inhibited the LPS-induced increase of the cytokines in spleen and lung. In the heart, CCK-8 significantly inhibited LPS-induced increase of TNF-α (864 ± 123 ng•L¯¹ in CCK-8 + LPS group vs 1599 ± 227 ng•L¯¹ in LPS group, P < 0.01), and IL-1β (282 ± 93 ng•L¯¹ in CCK-8+LPS group vs 621 ± 145 ng•L¯¹ in LPS group, P < 0.01).

CONCLUSION: CCK-8 reverses ES, which may be related to its inhibitory effect on the overproduction of cytokines.