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  • 作者:

    Objective: To investigate the expression levels of total and phosphorylation p38 , JNK and ERK1/2 protein during diethylnitrosamine ( DEN)-induced rat hepatocellular carcinoma occurrence and develop-ment. Methods: To induce hepatocellular carcinoma, we performed intermittently administrated DEN to rats. Using light microscopy and electron microscopy technique to discover that liver tissue morphological changes in the process. And then the expression of p38, JNK, ERK1/2 mRNA and protein was performed by RT-PCR and west-ern blot analysis, in order to furthermore explore the association of them. Results:In rat hepatoma model develop-ment, protein of p-p38、p-ERKl/2、p-JNK and its mRNA expression were significantly increased with increasing treatment time, but,no significant changes of p38, ERK, of JNK protein and its mRNA expression. Conclusions:During DEN-induced rat hepatocellular carcinoma, p-p38 and p-ERK proteins expressed lower and p-JNK pro-tein expressed high, and its expression was positively correlated with the development of hepatocellular carcinoma.

  • 作者:

    AIM The hepatic content of collagens (type I, Ⅲ and Ⅶ) and laminin (LN) in rat model of experimentalliver fibrosis was observed to find out their roles in the pathogenesis of liver fibrosis.METHODS The experimental rat model was established by immunological injury induced by injectinghuman albumin. Histopathological and immunohistochemical methods were used to measure the hepaticcontent of collagens and laminin in the fibrotic rat livers.RESULTS The hepatic contents of collagens (type I, Ⅲ, Ⅶ) and LN in the fibrotic rat livers weresignificantly increased as compared with those in the control group, and they were found to be mainlylocalized in the portal space, central veins and fibrous septa. Electron microscopic study showed that pro-collagens were present around the “activated” hepatic stellate cells (HSC) and the hepatocytes atrophied.CONCLUSION Pathological deposition of collagens (type Ⅰ, Ⅲ and Ⅶ ) and laminin was the fundamentallesion of liver fibrosis. HSC may be the major cellular source of collagens (type Ⅰ, Ⅲ and Ⅶ) and laminin inthe liver tissue.

  • 作者:

    AIM To observe the regulating effect of decoction shugan bushen (SGBS) on testosterone (Te) andadrenocortiotropin (ACTH).METHODS Fifty wistar male rats divided into four groups randomly, that is, normal group, hepaticfibrosis group, and two Chinese herb medicine treatment groups. The model of toxic hepatic fibrosis wasinduced by 0.5% dimethylnitrosamine (DMN). The decoction SGBS is composed of such herbs as bupleurumRoot. Dodder Seed, curcuma rood indianmulberry etc. According to the different doses of the drugs, ratsare divided into two groups in the treatment groups. The Chinese herb medicine treatment begins in a weekafter the second celiac injection of DMN, lastiong 8 weeks. The rats of normal group and hepatic fibrosisgroup are fed with distilled water once a day. After 11 weeks of Chinese herb medicine treatment, the Teand ACTH were tested insera of rats, and the livers were dissected for the pathology examination.RESULTS The results of pathology examination in rat livers of each group show that the hepatocytes of thenormal group have normal array, no degeneration and fibrosis. Those in the pathology group have obviousdegenerative necrosis and hepatic fibrosis, and in some cases show the evidence of cirrosis. The results intreatment groups are essentially similar to those of normal group. Variance analysis of least significantdifference (LSD) method is employed to compare the hormone level between groups. The serum levels of Teand ACTH in the normal group are 75.30±45.25 ng/dl and 141.02±68.70 ng/L. The levels in hepaticfibrosis group are obviously lower than those of normal group, as 19.77±16.92 ng/dl and 92.85±27.24ng/L, respectivite and with statistically different (P < 0.01 ). But that levels in the two treatment groups arerespectively 63.29±26.09 ng/dl 135.48±36.89 ng/L and 59.77±4.64 ng/dl, 130.8±17.35 ng/L, whichare obviously higher than those of pathology group and approximale to those of normal group (P>0.05).Two different doses make no obvious difference between the treatment groups (P>0.05).CONCLUSION SGBS can correct the hormone disturbance and shows the effect of anti-hepatic fibrosis.

  • 作者:

    AIM To study the liver-protecting and fibrosis-resisting effect of Ganxianning (GXN) and its mechanism.METHODS Model of carbon tetrachloride hepatic injury fibrosis rats was reproduced. In the experimentthere were six groups, the treatment groups with GXN's large, moderate and small dose (GXNb, GXNm andGXNs), the treatment group with colchicine, the blank model group and normal control group. The course of treatment was 30 days, then the rats were killed with their blood and liver tested.RESULTS In treatment groups, alanine aminotransferase (ALT) was lower than that in the model group(P<0.01), and albumin (Alb) higher than that in the model (P<0.01). Hydroxylproline (Hyp) and redcell membrane C3B receptor garland in GXNb's and GXNm's groups were lower and circulation complex(CIC) was slightly higher. Fibrinogen (Fb) in both colchicine and model groups was higher than that innormal group and the difference was significant (P<0.05, P<0.01). Compared with model group, acid-α-naphthyl acetate esterase (ANAE) increased in GXNb's and GXNm's groups (P<0.05, P<0.01). Underlight and electron microscopes, level of hepatic fibrosis of GXN groups was much lower than that of themodel group, P<0.01, and their difference was very significant. In GXNms group, liver cell was normal onthe whole and its chromatin was more than the model group and its nucleolus was evident.CONCLUSION GXN has rather good functions of protecting liver and resisting fibrosis, and thesefunctions are related to the increase of ANAE and C3b, decrease of CIC and Fb. and improvement of bodyimmunity function.

  • 作者:

    AIM To observe the effect of herbs-partition moxibustion on IL-1β and TNF-c in UC rats.METHODS The animal models were created by immunological method. They were divided into 5 groups atrandom, after treated by different methods, IL-1β and TNF-α in colon tissue of UC rats were detected withimmunologic technique.RESULTS In control group, there was a little or no IL-1β positive cell in colon mucosa. Compared withthat in rats of control group, the number of IL-1 positive cell in model group was much larger, and IL-1βcells with brown granules were mainly expressed in cytoplasm of macrophage in lamina propria of colon.Compared with model group, IL-1β positive cells in mild moxibustion group markedly decreased (P < 0.05),and those in electro-acupuncture group and herbs-partition moxibustion group decreased even more markedly(P < 0.01). The difference between the last two groups is evident (P < 0.05). TNF-α positive cells are not or seldomly found in UC rats, but in model group, these cells increasedevidently, which were mainly the macrophages in lamina propria of colon. Compared with those in modelgroup, the positive cells decreased markedly in electro-acupuncture group (P<0.05), and decreased moremarkedly in mild moxibustion group and in herbs-partition moxibustion group (P<0.01). There werestatistically significant differences between herbs-partition moxibustion group and electro-acupuncture group(P<0.05).CONCLUSION The mechanism of acupuncture and moxibustion may be that inhibited macrophageactivation, reduced expression of IL-1β and TNF-a and thereby blocking their further activation and thencontrolled, the initiated inflammation and its immunity cascade reaction and resulted in restoring the normalimmunity function and benefited in healing of ulcer.

  • 作者:

    AIM To investigate the effect of cold preservation on rat livers by modified storage method with self-madeHYD solution.METHODS The modified method was that the vascular bed of rat livers was expended with an additional20 mL, 30 mL and 40 mL self-made HYD solution / 100 g liver. After resection of the liver, the extra HYDsolution expressed as % liver weight was entrapped via portal infusion by tying off the supra- and infrahepatic inferior vena cava. According to the amount of extra HYD solution, 40 rats were randomly dividedinto four groups: control group with conventional storage method, 20% group, 30% group and 40% group.The preservation effect of modified storage method was compared with that of conventional storage methodusing isolated perfused rat liver model.RESULTS Bile production and all the indices of hepatic microcirculation including portal perfused pressure, endothelin in the effluent, Trypan blue distribution time and histology in modified method groupswere significantly superior to those in control group (P< 0.05). The liver enzymes in 30% group weremarkedly lower than those in control group (P<0.05). The preservative efficiency of rat liver in 30% groupwas the best among the modified method groups.CONCLUSION The cold preservative efficiency with modified storage method is obviously superior to thatwith conventional storage method. It is suggested that the modified cold storage method is effective and mayhave potential for liver preservation

  • 作者:

    AIM To determine the effect of glutathione (GSH) on stress gastric mucosal lesion.METHODS The stress gastric mucosal lesion as produced by restraint water-immersion in rats and gastricmucosal lesion, gastric mucosal GSH content, gastric acid secretion and gastric barrier mucus secretion wereexamined. We also observed the effect of GSH on gastric mucosal lesion and the effect of N-ethylmaleimine(NEM) and indomethacin on GSH protection. Comparisons between two groups were made using the Students t test.RESULTS GSH (100 and 200 mg/kg) intraperitoneally protected against stress gastric mucosal lesion(P<0.001 and P<0.001). Restraint water-immersion stress significantly reduced gastric mucosal GSHcontent (P < 0.001), but pretreatment with GSH (100 mg/kg) had no effect on gastric mucosal GSH content(P>0.05). The preinjection of NEM (10 mg/kg, sc.), a sulfhydryl-blocking reagent, or indomethacin(5 mg/kg, im.), a cyclooxygenase inhibitor, had no effect on protection of GSH (P>0.05). GSH(100mg/kg) significantly increased secretion of gastric barrier mucus (P<0.05), but had no effect onsecretion of gastric acid in restraint water-immersed rats (P >0.05).CONCLUSION GSH can inhibit the formation of gastric mucosal lesions induced by restraint water-immersion. The protective effect of GSH was due, in part, to promoting the secretion of gastric barriermucus, but not to suppress the gastric acid secretion. The protection effect of GSH has no relation withgastric mucosal GSH and PGs.

  • 作者:

    AIM To investigate the expression of endothelial NO synthase (eNOS), inducible NO synthase (iNOS)protein and eNOS mRNA gene in the splanchnic organs of liver cirrhosis and portal hypertensive rats.METHODS In control and CCl4-induced liver cirrhotic rats, the expression of eNOS and iNOS proteins wasdetected by immunohistochemical method, and eNOS mRNA was detected by in situ hybridization.RESULTS The expression of eNOS protein and eNOS mRNA increased in most organs of the cirrhotic rats,including bronchial and alveolar epithelial cells, renal tubular epithelial cells and mesenchyma, endothelialand adventitial cells of aorta and superior mesenteric artery, whereas no significant increase of iNOS proteinwas found. In the hepatic tissue, NOS protein and eNOS mRNA were present in mesenchymal cells and vesseladventitial cells, no difference was observed in the expression between control and cirrhotic rats.CONCLUSION The expression of NOS varied in region. In splanchnic organs and vasculars there was anincreased expression of eNOS which induced aplanchnic vasodilation and increased the inflow of portal vein,while in the liver tissue and blood vessel showed no increased expression, which may be associated withincreased intrahepatic vascular resistance.

  • 作者:

    AIM To study the protective effects of Weitongling decoction (WTL) on gastric mucosa.METHODS Rats with gastric lesion induced by dehydrated alcohol were used to observe the gastric mucosalblood flow (GMBF), rats with spleen deficiency syndrome induced by reserpine were applied to investigatethe D-xylose absorption rate, the Alcian blue binding properties of gastric wall, the gastric acid secretion andthe activity of pepsin.RESULTS Remarkable increases in GMBF (19.5±3.5 mL/min, 20.4±3.3 mL/min respectively in largedose group and small dose group, P<0.01), in Alcian blue binding properties of gastric wall (2.497 mg±0.138 mg, 2.223 ug±0.186 mg respectively in large dose group and small dose group, P<0.05) and in D-xylose absorption rate (1.287±0.043, 1.294±0.019 respectively in large dose group and small dose group,P<0.05) were found after administrations of WTL, while no significant alteration in gastric secretion wasshown and in vitro WTL did not neutralize gastric acid.CONCLUSION WTL can improve the Spleen deficiency syndrome, strengthen the gastric mucosal barrier,and thus protect gastric mucosa against injury agents.

  • 作者:

    AIM To observe the effect of acupuncture and moxibustion on the expression of IL-1β and iNOSmRNA inrats, with ulcerative colitis.METHODS Surgical samples of fresh human colonic mucosa was homogenized by adding appropriateamount of normal saline and centrifuged at 3000 r/min. Protein content of the supernatant was measuredand then mixed with Freund adjuvant, and injected into the plantae of the rats models, then into theplantae, dorsa, inguen and abdominal cavities (no Freund adjuvant for the last injection) on the 10th, 17th,24th and 31st day respectively. When serum titer of anti-colonic antibody has reached to a certain level,20 mL/L formalin and antigen fluid (no Freund adjuvant) were administered by enema to set up ulcerativecolitis rat mode. The animals were randomly divided into four groups: model control group (MC = 8),electroacupuncture group (EP=8), herbs partition moxibustion group (HPM= 8) and normal control group(NC=8). HPM: Mosa cones made of refined mugwort floss were placed on the medicinal pads (medicinalpad dispensing: Radix Aconiti Praeparata, cortex Cinnamomi, etc. ) for qihai (RN6) and tianshu (ST25,bilateral) and ignited. Two moxa cones were used for each acupuncture once a day and 14 times in all. EP:tisnshu (bilateral) and qihai were stimulated by the intermittent pulse with 2Hz frequency, 4mA intensity for20 minutes once a day and 14 times in all. After treatment, all rats were killed simultaneously. The spleenwas separated and distal colon was dissected. Total tissue RNA was isolated by the guanidinium thiocyanate-phenol-chloroform extraction method. RT-PCR technique was used to observe the expression of IL-1β andiNOSmRNA no Freund adjuvant.RESULTS IL-1β and iNOSmRNA were not detected in the spleen and colonic mucosa of NC rats, whilethey were significantly expressed in those of MC rats. IL-1β and iNOSmRNA were markedly lower in EF andHPM rats than those in MC rats. There were no significant difference in the levels of IL-1β and iNOSmRNAbetween EP and HPM rats. The amount of IL-1β and iNOSmRNA was nearly the same between the spleenand colon in different groups.CONCLUSION Acupuncture and moxibustion greatly inhibited the expression of IL-lβ and iNOSmRNA inthe ulcerative colitis rats.

  • 作者:

    AIM To study the clinical significance of alterations of serum hyaluronic acid in rats with carbontetrachioride-induced liver fibrosis.METHODS Rat liver fibrosis model was induced by carbon tetrachloride (CC14). The rats were divided intofive groups; group 1 (control): 0 week with no CCl4-inducing; group 2, 3, 4 and 5: 3, 6, 9 and 12 weeksafter CCl4-induction respectively. Serum HA level was analysed among various liver fibrosis groups andcontrol, and then compared the HA findings with the hepatic histopathology.RESULTS During rat liver fibrosis, serum HA levels of the liver fibrosis groups (group 2: 7.98ng/mL;group 3: 20.10 ng/mL; group 4:229.73 ng/mL; group 5:324,74 ng/mL) were significantly higher thanthat of control group (group 1:0.21 ng/mL) (P<0.01), in which group 4 and group 5 are much higher1094 times (229.73ng/mL/0.21 ng/mL) and 1546 times (324.74 ng/mL/0.21 ng/mL) than group 1respectively. When compared with each other, the serum HA levels are 38 times (7.98ng/mL/0.21 ng/mL; P<0.01, group 2 vs group 1); 2.5 times (20.10ng/mL/7.98 ng/mL; P<0.01, group 3 vsgroup 2); 11.4 times (229.73 ng/mL/20.10 ng/mL; P<0.01, group 4 vs group 3); 1.4 times (324.74 ng/mL/229.73 ng/mL; P<0.01, group 5 vs group 4) respectively.CONCLUSION The results demonstrated that the dynamic alterations of serum HA play an important rolein the early clinical diagnosis and staging of liver cirrhosis.

  • 作者:

    AIM To investigate the effects of low dosage of nitric oxide synthesis (NOS) inhibitor NG-nitro-L-argininemethyl ester (L-NAME) in long-term treatment on hyperdynamic circulatory state in rats with cirrhosis.METHODS Cirrhosis model was induced in male SD rats by injection of 60% CC14 oily solutionsubcutaneously. Cirrhotic rats were treated with L-NAME (0.5 mg·kg-1·d-1) by gavage for two weeks. Meanarterial pressure (MAP), cardiac output (CO), cardiac index (CI), splanchnic vascular resistance (SVR),splanchnic blood flow (SBF) and serum NO levels were determinded in L-NAME-treated, L-NAME-untreated cirrhotic rats and controls by using 57Co-Labled microsphere technique and a fluorometric assay,respectively.RESULTS Untreated cirrhotic rats had significantly lower MAP, SVR and higher PP, CO, CI, SBF andNO concentration than controls ( 14.42±0,47 kPa vs 17.05±0.34 kPa, 2.974±0.186 kPa·mL-1·min-1 vs4.234±0.118 kPa·mL-1·min-1, 1.665±0.067 kPa vs 1.123±0.096 kPa, 189.99±9.26 mL/min vs 135.5±3.55 mL/min, 55.89±1.82 mL-1·min-1·100g-1 BW vs 39.68±1.64 mL-1·min-1·100g-1 BW, 4.60±1.25μmol/L vs 0.53±0.26 μmol/L, P<0.01, respectively). In treated cirrhotic rats, L-NAME significantlyattenuated the increase of CO, CI, SBF, NO concentration and the decrease of MAP and SVR. In treatedcirrhotic rats, L-NAME induced a marked decrement of NO concentration than untreated cirrhotic rats(1.471 ±0.907 μmol/L vs 4.204±1.253 μmol/L, P<0.01).CONCLUSION The endogenous NO may play an important role in the changes of hemodynamics pattern incirrhosis,and hyperdynamic circulatory state in rats with cirrhosis can be ameliorated by long-term low doseL-NAME treatment.

  • 作者:

    AIM To evaluate the effect of chitosan on rat body weight, concetration of plasma leptin and serumtestosterone.METHODS Five groups of rats were respectively given access to basic diet, high fat diet and high fat dietwith different doses of chitosan (1.5%,3.0% and 6.0% of chitosan in high fat diet respectively) for 7 wk.All rats were weighed once a week. By the end of wk 7, the animals were sacrificed and their blood sampleswere taken, the concentration of plasma leptin and serum testosterone were determined by RIA Kit method.RESULTS At the end of wk7, the average body weight of rats treated with high-fat diet was 67.3 gheavier than that with the basic diet, however, the average body weight of rats treated with high doses of chitosan in high-fat diet was 56.3 g lighter than that with high-fat diet (P < 0.01). In addition, plasma leptinconcentration in rats treated with high fat diet was significantly different from those with basic diet(P<0.01); plasma leptin concentration in rats treated with high dose of chitosan in high-fat diet wassignificantly lower than those with high-fat diet (P<0.01), but was significantly higher than those withbasic diet (P<0.05). Serum testosterone level in rats treated with high-fat diet was significantly lower thanthose with basic diet (P<0.01). Serum testosterone levels in rats administrated high dose of chitosan inhigh-fat diet were sighificantly lower than those with high-fat diet (P<0.01).CONCLUSION Chitosan prevents the increase of rat body weight induced by high-fat diet, and lowersplasma leptin and serum testosterone in rats.

  • 作者:

    AIM To observe the therapeutic effect of Welcome on gastric mucosal dysplasia in rats.METHODS Rats with gastric mucosal dysplasia induced by MMNG and heat-damage were treated withWelcome, a kind of traditional Chinese medicine compound which has the functions of replenishing qi toinvigorate the spleen, and of nourishing the liver and kidney and clearing away heat and toxic materials, thecontrol rats were treated with saline and tretinoin.RESULTS AND CONCLUSION The results showed Welcome could obviously block the mutagenic action ofMNNG and prevent the occurrence of gastric mucosal dysplasia of rats.

  • 作者:

    AIM To investigate a mixture of traditional Chinese medicine (TCM) in the prevention of chronic colitis inrats.METHODS Sixty rats were divided into 3 groups. Colitis was induced by trinitrobenzene-sulfonic acid(TNB). On day 10, all the survived rats were killed, the mortality and intestinal obstruction rate werecalculated, the colonic lesion score was assessed and collagenase activity and collagen concentration weremeasured.RESULTS The survival rate was much lower and intestinal obstruction rate much higher in TNB than thosein TCM, they were 53% and 81% vs. 80% and 24% (P<0.05 and P<0.01, respectively). There were alsosignificant differences in colonic stricture score and colonic weight between TNB and TCM groups (1.75±1.2 vs 0.22±0.67 and 0.57±0.36 vs 0.31±0.10, P<0.01 and P<0.05, respectively). No hydroxyprolineand collagenase activity differences were found between the two groups.CONCLUSION This mixture of TCM prevents the formation of intestinal stricture, increases the survivalrate and decreases intestinal obstruction rate in a rat model of chronic colitis.

  • 作者:

    AIM To establish an ideal model of gastric precancerous lesions for rats.METHODS Fifty rats were fed with carcinogen MNNG for 35 wk and heat-plaste at 60C for 20 wk, thepathological changes were observed. Data in the groups were analyzed by Ridit test.RESULTS The occurrence rate of dysplasia in rats due to MNNG and heat-damage was 65%, which wasobviously higher than that due to MNNG only. The differences between the two groups were significant.CONCLUSION The animal model made by MNNG and heat-damage was an ideal one which could be usedto investigate the pathologic mechanism of gastric precancerous lesions.

  • 作者:

    Site-specific delivery of therapeutic drugs to their target cells is a major scientific challenge for the pharmaceutical sciences. It offers a number of advantages over conventional drug administration. With drug targeting, high local concentrations of the drug can be achieved, thus circumventing many unwanted side effects. Various carriers have been suggested for the delivery of drugs, including liposomes[1 - 5] and (neo ) glycoproteins[6-8]. The asialoglycoprotein receptor (ASGP-R) has frequently been utilized for targeting drugs to the parenchymal liver cell[6- 12]. Liposomes have several advantageous characteristics as drug carrier, and particularly, ligandtacked liposomes achieve a highly effective targeting[13]. Hara et al reported that asialofetuin (AF)-tacked liposomes distributed to rat hepatocytes selectively in vivo[14], and ASGP-R mediated the uptake of AF-liposomes encapsulating IFN-γ by isolated rat hepatocytes in vitro[15]. Lactosaminated human serum albumin (L-HSA) is a neoglycoprotein taking number of galactose residue as terminal sugar[6].

  • 作者:

    INTRODUCTIONEndothelins (ETs) has a potent and sustained vasoconstrictive effect on a variety of blood vessels.The vascular smooth muscle cell (VSMC) is the target for ETs. VSMC of the whole body contains endothelin receptor (ETR)[1]. A great number of experiments have shown that three distinct complementary DNAs of ETR have been identified i. e., endothelin A receptor (ETA receptor),endothelin B receptor ( ETB receptor ) and endothelin C receptor (ETc receptor). ETA receptor was expressed in VSMC responsible for the contraction[2]. The aim of this study is to confirm the effects of endotoxin on the activity of ETR, and the transcription and expression of ETA receptor mRNA in hepatic and intestinal tissues.

  • 作者:

    It has been reported in many studies that electroacupuncture (EA) can positively regulate erythrocytic immunity and T-lymphocytic subgroups[1-8].Nevertheless, its mechanism remains to be explored. In the present study, a multi-group, multi-stepped and multiindexed observation was conducted on the effects of EA on erythyrocytic immunity and T-lymphocytic subgroups. A simultaneous assay of the changes in immunoreactivesubstance-P (ir-SP) content in the pituitary gland and peripheral blood was also carried out. The objective of the study was to investigate the regulatory effects of the immune system and their possible mechanism in the treatment of relevant diseases with EA.

  • 作者:

    INTRODUCTION Although liver transplantation for irreversible liver diseases is increasingly prevalent worldwide, patient die while waiting for donors because of organ shortages. One important problem commonly encountered is that fatty livers often affect the outcome of liver transplantation. It is reported that the incidence of abnormal fatty livers in autopsies after accidental death ranged from 15% to 24%.Since fatty livers may result in a primary nonfunction (PNF) liver graft, which contributes to an increased risk of mortality[1], they are usually out of consideration in liver transplantation.However, some fatty livers can be successfully transplanted. Therefore, how to choose fatty livers as donor organs correctly is the crux of success in liver transplantation.

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