[Change of zero-stress state of portal vein in the rat during the pathogenesis of intrahepatic portal hypertension]

A model of intrahepatic portal hypertension was established in SD rats by injection of carbon tetrachloride (CCl4). By observing the opening angle of the portal vein, the zero-stress state of the portal veins was studied at different time during the pathogenesis of intrahepatic portal hypertension. After CCl4 injection, the opening angles of the portal veins were increased, in the tenth week, they were much greater than those in the corresponding controls (P<0.05). The results suggest that during the pathogenesis of portal hypertension, unequal remodeling exists in the portal veins to change its biomechanical properties, and the residual stress and strain of the portal veins in portal hypertensive rats are greater than those in normal controls.

[Establishment of a rat model of alcoholic liver fibrosis induced by complex factors]

OBJECTIVE

To establish a model of alcoholic liver fibrosis (ALF) in rats induced by complex factors.

METHODS

Forty-seven healthy male rats were divided into three groups: normal control group (n=12), minor CCl4 group (n=12) and complex factors group (n=27). The rats in the complex factors group were fed a complex diet including alcohol, corn oil and pyrazole, and administered with intraperitoneal injection of minor CCl4 to induce ALF. During induction process, the histopathological changes of liver tissue and the values of liver-to-body weight ratio were both observed regularly. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (gamma-GT) in these three groups were all examined at the 12th week of the induction process.

RESULTS

At the 12th week of the induction process, the model of ALF induced by complex factors was successfully established in rats, and the histopathological presentations showed alcoholic fatty liver, hepatitis and liver fibrosis in a sequence along with the induction process. The value of liver-to-body weight ratio and the serum levels of ALT, AST and gamma-GT of rats in the complex factors group were all significantly different from those in the other two groups.

CONCLUSION

It is a steady and effective way to induce ALF in rats with complex diet and minor CCI4 injection.

[Protective effects of yanggan lidan granules on carbon tetrachloride-induced liver damage in mice]

OBJECTIVE

To observe the protective effects of Yanggan Lidan Granules (YGLDG) on carbon tetrachloride (CCl(4))-induced liver damage in mice and to find out its mechanism.

METHODS

A model of chronic liver damage was established in mice by intraperitoneal injection of CCl(4). After three weeks, those model mice were treated with low-, medium-, high-dose YGLDG, Danning Tablets and bifendate respectively for four weeks. Then the levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), as well as the contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in liver tissues were detected.

RESULTS

YGLDG could significantly reduce the levels of serum ALT and AST in model mice, and the content of MDA was obviously decreased while the content of SOD was increased in liver tissue.

CONCLUSION

The therapeutic effect of YGLDG on mice with CCl(4)-induced liver damage is to relieve the seriousness of liver damage, and its mechanism may relate to reducing peroxidation activity in liver tissue.

[Effects and comparison of seed oil and sarcocarp oil of Hippophae rhamnoides on rats with experimental hepatocirrhosis]

OBJECTIVE

A study was carried out to investigate the effects of seed oil and sarcocarp oil of Hippophae rhamnoides on rats with experimental hepatocirrhosis, and comparison between the two.

METHOD

A rat model of experimental hepatocirrhosis was set up by feeding CCl4. Different concentration of seed oil and sarcocarp oil of H. rhamnoides were feed to those rats for 45 d, then the changes of activity of ALT in serum and SOD in liver were measured.

RESULT

Both of seed oil and sarcocarp oil can control the increase of ALT in serum and the decrease of SOD evidently, and the effect of seed oil was turn out to be a little better than sarcocarp oil.

CONCLUSION

Seed oil was more effective than sarcocarp oil of H. rhamnoides in alleviating liver injury caused by CCl4.

[Effect of Hovenia dulcis extract on expression of MMP-13 and TIMP-1 in hepatic tissue]

OBJECTIVE

To investigate the effects of Hovenia dulcis extract on mRNA expression of MMP-13 and TIMP-1 mRNA in hepatic tissue in experimental rats.

METHOD

48 male Sprague-Dawley rats were randomly divided into 2 groups: normal group (16) and model group (32), hepatic fibrosis was induced by CCl4 for 6 weeks in rats, 8 rats were sacrificed at the end of the 6th week from every group respectively, HE staining of hepatic tissue was performed; In the model group, rats randomly subdivided into 3 groups: spontaneous recovery group, control group and medication administration group, 8 rats were sacrificed at the end of the 12th week from every group respectively, the mRNA levels of MMP-13 and TIMP-1 in hepatic tissue were assayed by semi-quantitative RT-PCR.

RESULT

The mRNA expression of MMP-13 among the 4 groups were not statistically significant, but the mRNA expression of TIMP-1 among the 4 groups were statiscally significant. The levels of TIMP-1 mRNA were significantly increased in control group and medication administration group compared, with those in the model group (P < 0.05), and reverse effects of medication administration groups were significantly high than those of control group (P < 0.05).

CONCLUSION

Inhibition of the mRNA expression of TIMP-1 may be the mechanism of reversing hepatic fibrosis H. dulcis, for thus collogen degradation system was recoveried gradually.

[The effect of Fuzheng Huayu Decoction on the hepatic proteome during the formation and resolution of rat liver fibrosis]

OBJECTIVE

To investigate the dynamic changes of the hepatic proteome during the formation and resolution of rat liver fibrosis induced by carbon tetrachloride and the effect of Fuzheng Huayu Decoction on it.

METHODS

Liver fibrosis in Wistar rats was induced by subcutaneous injection of 40% CCl4 in olive oil while the rats in the treatment group received Fuzheng Huayu Decoction. Pathological examination, hydroxyproline content determination and protein extraction of the rats livers were performed at four time points, i.e. at the end of 4, 8, 12 and 16 weeks. After 2-dimensional electrophoresis (2-DE), the gels were analyzed using the PDQUEST 2-DE image analysis software and differentially expressed proteins were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS).

RESULTS

(1) The 2-DE examination showed that the model group-specific proteins and differentially expressed proteins presented started at 4 weeks and reached their peaks at 12 weeks, and this was conformed by MALD-TOF-MS identification. (2) In addition, 18 proteins were present at all time points and another 19 proteins were absent in the model group among those identified by MALD-TOF-MS. (3) Fuzheng Huayu Decoction down-regulated proteins and their expressions increased at 4 and 8 weeks, whereas it up-regulated those which decreased at 8, 12 and 16 weeks.

CONCLUSIONS

(1) The changes in protein expressions, which effect metabolism, neuroendocrine function and cell proliferation, are the basis of liver fibrosis. (2) The anti-fibrotic effect of Fuzheng Huayu Decoction is holistic, specifically because it can decrease the abnormal cell proliferation and can increase the synthesis of normal proteins.

[Effect of prostaglandin E1 on the expression of tissue inhibitor of metalloproteinase-1 in experimental liver fibrosis rats]

OBJECTIVE

To investigate the effect of prostaglandin E1 (PGE1) on the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) in experimental liver fibrosis rats.

METHODS

The liver fibrosis model was established by carbon tetrachloride. Rats were divided into a control group and PGE1-treated group. The pathological changes of the liver tissue from the two groups, the semi-quantitative analysis of hepatitic activity in HE stain sections, the pathological image quantitative analysis of the fibrosis degree, TIMP-1 positive cells, and the content of collagen were synthetically analysed.

RESULTS

The mark changes of liver pathology in HE stain sections were that the degree of hepatitic activity in the PGE1-treated group was obviously lower than that in the control group (P < 0.05). The fibrosis degree, TIMP-1 positive cells and the collagenous fibers decreased in the PGE1-treated group (P <0.05).

CONCLUSION

PGE1 has an anti-hepatofibrosis effect in the experimental rats, the inflammation of liver is light, and the proliferation of collagenous fibers can be restrained, whose mechanism is probably associated with the suppression of TIMP-1 expression caused by PGE1.

[Evaluation of the liver reserve using lidocaine test on experimental liver injuries in rats]

OBJECTIVES

To study the effectiveness of the lidocaine test in evaluating the liver reserve of rats with experimental liver injury in different phases.

METHODS

40 healthy male Wistar rats were divided randomly into experimental and control groups. Rats of the experimental group received subcutaneous CCl4 in oil injection, and rats of the control group received saline injections. Monoethylglycinexylidide (MEGX) test, common hepatic function tests and histological examination of the livers were performed on all the rats.

RESULTS

With the development of the severity in liver injury, the concentrations of the serum MEGX in lidocaine test decreased gradually, which were consistent with liver histological changes. However, the results from the common liver function tests were all abnormal in the experimental group and were not consistent with the liver histological changes.

CONCLUSION

The results obtained from the MEGX test are more agreeable to liver histological changes than those from common liver function tests. The results from the MEGX test can represent liver histological changes concisely.

[Prophylactic effect of curcumin on hepatic fibrosis and its relationship with activated hepatic stellate cells]

OBJECTIVE

To observe the prophylactic effect of curcumin on hepatic fibrosis and the number, location, apoptosis of activated hepatic stellate cells (HSCs) in the livers and to discuss the relationship between the prophylactic effects and activated HSC.

METHODS

A rat model of hepatic fibrosis was established by intraperitoneal injection of carbon tetrachloride. Curcumin doses of 5 mg, 10 mg, 20 mg per 100 gram per 100g of body weight were given to three groups of the model rats. No curcumin was given to one group of the model rats and it served as the control. After eight weeks, all rats were sacrificed and their left liver lobes were examined histopathologically with H.E and Masson stainings. Grades of hepatic fibrosis were evaluated according to the SSS system. Activated HSC was detected by the alpha-SMA immunohistochemistry staining. HSC apoptosis was detected by double-stainings of terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) and desmin immunohistochemistry staining.

RESULTS

Degrees (SSS system scores) of hepatic fibrosis in the curcumin groups were all less severe in comparison with those of the control group. Activated HSCs in the livers of the rats of the control group increased significantly compared with that of the treatment groups, and also fewer apoptotic HSCs were detected in the control group. On the contrary, fewer activated HSCs and more apoptotic HSCs were detected in the curcumin groups compared with those of the control group. The degrees of the effects were curcumin dose-dependent.

CONCLUSIONS

Curcumin can prevent hepatic fibrosis. It can inhibit activation and proliferation of HSCs and induce HSCs apoptosis, which may be the mechanism(s) contributing to the prophylactic effects of curcumin on hepatic fibrosis.

[Protective effect of Isodon lophanthoides var. gerardianus on acute hepatic injury induced by carbon tetrachloride in rats]

OBJECTIVE

To study the protective effects of Isodon lophanthoides var. gerardianus (ILVG) aqueous extract on the acute hepatic injury induced by carbon tetrachloride (CCl4) in rats.

METHOD

Sixty rats were allocated into control group, model group, low, middle and high dosage group and Bifendate group randomly. At the test group, rats received either ILVG aqueous extract (15, 7.5, 3.75 g x kg(-1)) or Bifendate (45 mg x kg(-1)) by gastric perfusion daily for 10 consecutive days. In 1st, 4th, 7th and 10th days, 10% CCl4 (2 mL x kg(-1)) was given to rats by intraperitoneal (ip) injection. The rats were killed 24 h after the last adminiction with drug, the levels of ALT, AST, ALP and total bilirubin in serum were analyzed, the body weight, liver weight, spleen weight and thymus weight of each rat were measured, and the hepatic tissue pathology was observed.

RESULT

ILVG could decrease the ALT, AST, ALP and T-Bil in serum, restrain the enlargement of liver and the shrinkage of thymus, and reduce the necrosis in pathological observation.

CONCLUSION

ILVG aqueous extract possesses the effects of protecting on the acute hepatic injury induced by CCl4 in rats.

[Protective effect of dl-tetrahydropalmatine on liver injury induced by carbon tetrachloride in mice]

OBJECTIVE

To study the protective effect of dl-tetrahydropalmatine(dl-THP) on liver injury induced by carbon tetrachloride (CC4) in mice.

METHOD

Mice were administracted with dl-tetrahydropalmatine ip 20, 40 mg x kg(-1) daily for 9 d respectively, and then actue liver injury model was induced by 0.1% carbon tetrachloride ip 20 mL x kg(-1). The mice were killed 17 h after injection ip of CCl4, serum alanine and aspartate aminotransferase (ALT and AST) activity were measured, and maleic dialdehyde (MDA) and superoxide dismutase(SOD) activity in liver were detected.

RESULT

dl-THP significantly reduced the level of serum ALT and AST, inhibited lipoperxidation in liver, while increased SOD activity in liver tissue. Degeneration of hepatocytes was obviously prevented in mice treated with dl-THP, and the liver histological structure was well maintained.

CONCLUSION

dl-THP has inhibitory effects on liver injury induced by CCl4 in mice. The mechanisms may be related with its effects of reducing lipid peroxidation product.

[Resolution of racemic anti-hepatitis drug ( +/- ) -bicyclol]

AIM

To study the different biological activities of the enantiomers of the anti-hepatitis drug (+/-)-bicyclol, the (+/-)-bicyclol was resolved.

METHODS

By being treated with optically active alkaloid, the two diastereoisomers alkaloid salts of the compound could be obtained, separately. After decomposing and methylating, they were transformed separately into (-)-bicyclol and (+)-bicyclol.

RESULTS

The two enantiomers of bicyclol were determined by melting point, [alpha]D, 1H NMR, MS and chiral column HPLC.

CONCLUSION

Comparison of hepatoprotective action of racemic bicyclol and (-)-, (+)-bicyclol on experimental liver injury, the effect of (-)-bicyclol was two times more potent than that of racemic bicyclol and the potency of (+)-bicyclol was much less than that of the racemate.

[The changes of advanced glycation end products in a rat liver fibrosis model and the interventional effect of aminoguanidin]

OBJECTIVE

To study the changes of advanced glycation end products (AGEs) in different phases of a rat liver fibrosis model induced by CCl4, and the interventional effect of aminoguanidin (AG).

METHODS

Fifty-four SD rats were divided into three groups: a control group, a CCl4 model group and an intervention group. Their blood serum AGEs and hyaluronic acid (HA) and AGEs in their liver homogenates were measured. These measurements were correlatively assessed to the degrees of liver fibrosis at different phases of the rat model before and after the intervention with aminoguanidin.

RESULTS

The content of AGEs in their blood sera and liver homogenates, and the level of blood serum HA, and the score of liver fibrosis degree at week 12 in our rat liver fibrosis mode groups were significantly higher than those in the control group (P < 0.01). In the intervention group with aminoguanidin, these figures were lower than those in the liver fibrosis model group (P < 0.05). The content of AGEs in their blood sera and liver homogenates had a linear correlation with the level of HA in their blood sera.

CONCLUSION

The contents of AGEs in their blood sera and liver homogenates were increased in the late phase of our rat liver fibrosis model. To some extent, the level of AGEs may reflect the fibrosis degree of the rat livers. Aminoguanidin has an interventional effect in our CCl4 induced rat liver fibrosis model.

[Detecting the activity of antibodies induced by recombinant TGFbeta1 vaccine]

OBJECTIVE

To measure the neutralization activity in vitro of the antibodies induced by recombinant TGFbeta1 vaccine and to evaluate the vaccine's anti-liver fibrosis activity.

METHODS

Balb/c mice were immunized with a fusion protein of the human TGFbeta1 epitope-inserted into a hepatitis B core antigen using a prokaryotic expression system. The antibody produced by the recombinant vaccine was determined using ELISA. The biological activity of the anti-TGFbeta1 antibody induced by the vaccine was measured by MTT using mink lung epithelial cell Mv-1-Lu as inhibiting cells. The fusion protein was used as a vaccine in a mice hepatic-fibrosis model.

RESULTS

A high titer of anti-TGFbeta1 antibody and a low of anti-HBc antibody were detected in the mice after the immunization. The serum antibodies induced combined with the fusion and antigenic peptide prevented the TGFbeta1 inhibiting activity in the Mv-1-Lu cell.

CONCLUSION

Recombinant fusion protein can be used as a cytokine vaccine to induce high titers of anti-TGFbeta1 antibodies. Our results show the potentiality of the fusion protein to be used as a vaccine for preventing liver fibrosis.

Y-box Protein-1 Is the Crucial Mediator of Antifibrotic Interferon-γ Effects

Y-box protein-1 (YB-1) is a known negative regulator of collagen (Col) expression by two different mechanisms, acting directly through binding to an interferon-gamma response element within the col1A2 promoter and/or by physically interacting with p300/Smad3, thereby abrogating the stimulatory effect of transforming growth factor-beta (TGF-beta). Here, we report that YB-1 activation via the Jak1 signaling pathway is required and sufficient to confer interferon-gamma-dependent activation of the smad7 gene. By binding to a bona fide recognition site within the smad7 promoter, YB-1 up-regulates smad7 transcription, which was additively enhanced by autoinhibitory TGF-beta signaling. Importantly, the anti-TGF-beta effect was not only supplied by induced Smad7 expression but was recapitulated in the context of the col1A2 promoter, where YB-1 overexpression abolished the trans-stimulatory TGF-beta effect in a dominant fashion. In conclusion, YB-1 is the main target of interferon-gamma signaling via Jak1 that exerts antifibrotic action by both interference with TGF-beta signaling and direct down-regulation of collagen expression.

Protective effect of Aronia melanocarpa fruit juice pretreatment in a model of carbon tetrachloride-induced hepatotoxicity in rats

The main active ingredients of Aronia melanocarpa fruit juice (AMFJ) are phenolic substances, mainly flavonoids from the anthocyanin subclass.

AIM

The aim of the present study was to investigate the effect of AMFJ applied as pretreatment in a model of carbon tetrachloride (CCl4)-induced hepatotoxicity in rats.

MATERIAL AND METHODS

AMFJ was given orally to rats for 2 days at doses of 5, 10 and 20 ml/kg either alone or as pretreatment before the oral application of CCl4 (0.2 ml/kg, 2 days). The plasma activities of aspartate transaminase (AST) and alanine transaminase (ALT) were measured as markers of the liver cell damage. The levels of malondialdehyde (MDA), a lipid peroxidation marker, were determined in rat liver and plasma.

RESULTS

Administration of CCl4 caused an elevation of plasma AST and ALT activities. It also induced an elevation of MDA levels in rat liver and plasma. AMFJ applied alone in the tested doses did not cause any significant changes in the measured enzyme activities and in MDA levels. AMFJ applied as pretreatment prevented the CCl4-induced increase of AST and ALT activities, and also prevented the elevation of plasma and liver MDA levels.

CONCLUSIONS

AMFJ showed a protective effect in a model of CCl4-induced hepatotoxicity in rats. This effect might be due to the antioxidant activity of its active ingredients.

[Experimental study of liver fibrosis reversal effect of warming-yang compound formula ganzhifu]

OBJECTIVE

To observe the effect of Ganzhifu (GZF), a Chinese compound formula for Warming-yang on experimental hepatic fibrosis, and to explore its mechanism.

METHODS

Fifty-nine Wistar rats were divided into the normal control group and the model group. After the hepatic fibrosis model was established in rats by subcutaneous injection of CCl4 and feeding 10% alcohol in the model group, the rats were randomly sub-divided into the Ganzhifu group, colchicine group and model group, they were treated with Ganzhifu, colchicine and normal saline of same volume once a day respectively for 30 days as one treatment course. The serum liver function and hepatic fibrosis indexes, liver tissue contents of hydroxyproline (Hyp), malondialdehyde (MDA) and superoxide dismutase (SOD) activity were measured at the end of the experiment. Histologic changes of liver tissue were observed and scored by the modified inflammatory activity and fibrosis semiquantative scoring system (SSS), and collagen type I , III and IV in liver tissue were stained and semiquantitive analysis conducted.

RESULTS

In the Ganzhifu group, liver function and inflammatory activity and fibrosis SSS scores were markedly improved, indexes of hepatic fibrosis, liver contents of Hyp, MDA and collagen type I, III and IV were significantly decreased, and the SOD activity was increased, the changes were more significant as compared with those in the model group. The protective effect of Ganzhifu against hepatic fibrosis was the same as that of colchicine.

CONCLUSION

Ganzhifu can alleviate or reverse hepatic fibrosis in experimental hepatic fibrosis, and antioxidation may be its mechanism.

[Effects of nuclear factor kappaB and transforming growth factor beta1 in the anti-liver fibrosis process using Ginkgo biloba extract]

OBJECTIVE

To evaluate the effects of Ginkgo biloba extract (EGB) on CCl(4)-induced liver fibrosis and to investigate the underlying mechanisms.

METHODS

Rats were divided into the following groups: normal control group, CCl(4) model group, low dose EGB group, moderate dose EGB group and high dose EGB group. The rat liver fibrosis model was induced by intraperitoneal injection of CCl(4) twice a week for 8 weeks. The model rats of the three EGB treated groups were given 0.25 g/kg, 0.5 g/kg, 1.0 g/kg of EGB by stomach tubes every day. At the end of the eighth week, the blood and liver specimens were obtained. The expressions of nuclear factor kappaB (NF-kappaB) P65, and alpha-smooth muscle actin (alpha-SMA) were detected by immunohistochemistry. Radioimmunoassay was exploited to evaluate serum hyaluronic acid (HA) and laminin (LN) levels. Electrophoretic mobility shift assay (EMSA) was used to confirm the nuclear translocation activity of NF-kappaB in liver tissues. The mRNA expression of transforming growth factor-beta1 (TGFbeta1) and collagen I was determined by RT-PCR. Malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in liver tissues and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the sera were also examined.

RESULTS

CCl(4) administration induced liver fibrosis, which was inhibited by EGB in a dose-dependent manner. The histopathologic scores of liver fibrosis, the levels of serum ALT, AST, HA and LN were significantly lower in the rats treated with EGB compared with those not treated (P <0.01 or P <0.05). SOD and GSH-Px activities were notably elevated and MDA content was significantly lower in the rats treated with EGB (P <0.01 or P <0.05), indicating reduced oxidative stress. Immunohistochemical staining demonstrated inhibition of hepatic stellate cell (HSC) activation (in terms of alpha-SMA expression) and NF-kappaB P65 expression in the livers of the EGB-treated rats. As determined by EMSA and RT-PCR, activation of NF-kappaB, the mRNA expression of TGFbeta1 and collagen I were significantly higher in model group rats, but obviously lower in EGB treated rats.

CONCLUSION

EGB is able to ameliorate liver injury and prevent rats from CCl(4)-induced liver fibrosis by suppressing oxidative stress. This process may be related to inhibiting the expression of TGFbeta1 and the induction of NF-kappaB on HSC activation.

[Protective effects of the granule of Sambucus chinensis lindl on acute hepatic injury]

OBJECTIVE

To investigate the protective effects of the granule of Sambucus chinensis Lindl on acute hepatic injury.

METHODS

The acute liver-injury model induced by CCl4 or D-GalN or ConA was established in mice or rats.

RESULTS

The granule of Sambucus chinensis Lindl showed significantly protective effects on mice acute hepatic injury induced by CCl4 ,and the effects were concern of antagonizing lipoperoxidation and improving energy of Ca2+ -ATPase of theca mitochondria and microsome. It showed significantly protective effects on mice or rats acute hepatic injury induced by D-GalN or Con A, too.

CONCLUSION

The granule of Sambucus chinensis Lindl showed significantly protective effects against many kinds of chemical and immunological liver injuries.

[Changes of gene expression profiles in CCl4 injured liver of mice]

AIM

To study the gene expression profiles between the CCl4 injured liver and normal liver in mice, and to screen the differentially expressed genes that relate to liver injury by CCl4 on a large scale using cDNA microarrays.

METHODS

Male Kunming strain mice were divided into two groups: one was control group and another was CCl4 injured liver group that was given 0.1% CCI4 oil solution ip at dose of 10 mL x kg(-1) every three days, totally for ten times. Then mRNA in livers of the two groups of mice was extracted, separately, and reversely transcribed to cDNA with the incorporation of different fluorescent-labeled dUTP as the hybridization probes. The mixed probes were hybridized to the cDNA microarrays. The fluorescent signal values were acquired by scanner and analyzed with statistical software.

RESULTS

Among the 14 100 target genes, 379 genes were differentially expressed, in which 163 genes were up-regulated and the other 216 genes were down-regulated. They are closely related to a range of biological functions.

CONCLUSION

Using the cDNA microarray and experimental animal modeling technique, the differentially expressed genes of CCl4 injured liver in mice on a large scale could be studied. It is useful for further investigation of the injury mechanism of CCl4.

Increased apical targeting of renal epithelial sodium channel subunits and decreased expression of type 2 11beta-hydroxysteroid dehydrogenase in rats with CCl4-induced decompensated liver cirrhosis

It was hypothesized that dysregulation of renal epithelial sodium channel (ENaC) subunits and/or 11beta-hydroxysteroid dehydrogenase (11betaHSD2) may play a role in the increased sodium retention in liver cirrhosis (LC). Experimental LC was induced in rats by CCl(4) (1 ml/kg, intraperitoneally, twice a week) for 12 wk (protocol 1) or for 11 wk (protocol 2). In both protocols, one group of rats with cirrhosis showed significantly decreased urinary sodium excretion and urinary Na/K ratio (group A), whereas a second group exhibited normal urinary sodium excretion (group B) compared with controls, even though extensive ascites was seen in both groups of rats with cirrhosis. In group A, protein abundance of alpha-ENaC was unchanged, whereas beta-ENaC abundance was decreased in the cortex/outer stripe of outer medulla compared with controls. The gamma-ENaC underwent a complex change associated with increased abundance of the 70-kD band with a concomitant decrease in the main 85-kD band, corresponding to an aldosterone effect. In contrast, no changes in the abundance of ENaC subunit were observed in group B. Immunoperoxidase microscopy revealed an increased apical targeting of alpha-, beta-, and gamma-ENaC subunits in distal convoluted tubule (DCT2), connecting tubule (CNT), and cortical and medullary collecting duct segments in group A but not in group B. Immunolabeling intensity of 11betaHSD2 in the DCT2, CNT, and cortical collecting duct was significantly reduced in group A but not in group B, and this was confirmed by immunoblotting. In conclusion, increased apical targeting of ENaC subunits combined with diminished abundance of 11betaHSD2 in the DCT2, CNT, and cortical collecting duct is likely to play a role in the sodium retaining stage of liver cirrhosis.