Taurocholic acid feeding prevents tumor necrosis factor-alpha-induced damage of cholangiocytes by a PI3K-mediated pathway

Cholangiopathies, such as primary biliary cirrhosis and primary sclerosis cholangitis, are characterized at the end stage by ductopenia due to increased cholangiocyte apoptosis and decreased cholangiocyte proliferation. Although cholangiocyte proliferation is associated with an increased number of intra-hepatic bile ducts and secretin-stimulated ductal secretion, ductopenia is coupled with decreased ductal mass and secretin-induced ductal secretory activity. We have shown that a single injection of actinomycin D + tumor necrosis factor-alpha (TNF-alpha ) to bile duct-ligated (BDL) rats induces cholangiocyte injury, which is characterized by loss of cholangiocyte proliferation, and secretory activity and by an increase in cholangiocyte apoptosis. We also have shown that taurocholic acid both in vivo and in vitro stimulates cholangiocyte proliferation. We hypothesize that taurocholic acid feeding protects cholangiocytes against TNF-alpha -induced apoptosis through a phosphatidylinositol-3-kinase (PI3K)-dependent pathway. Immediately after BDL, rats were fed taurocholic acid or control diet in the absence/presence of daily injections of wortmannin for 1 week. Seven days later, control-fed or taurocholic acid-fed rats were treated with a single intraperitoneal injection of actinomycin D + TNF-alpha . Twenty-four hours later we evaluated: (i) cholangiocyte apoptosis and proliferation in liver sections and (ii) basal and secretin-stimulated bile and bicarbonate secretion in bile fistula rats. Taurocholic acid feeding prevented TNF-alpha -induced increases in cholangiocyte apoptosis and decreases in growth and secretin-stimulated bile and bicarbonate secretion, changes that were blocked by PI3K inhibition. The PI3K survival pathway is important in bile acid protection against immune-mediated cholangiocyte injury in cholestatic liver diseases.     

S-allyl cysteine prevents CCl4-induced acute liver injury in rats

Aged garlic extract (AGE) possesses multiple biological activities. We evaluated the protective effect of S-allyl cysteine (SAC), one of the organosulfur compounds of AGE, against carbon tetrachloride (CCl₄)-induced acute liver injury in rats. SAC was administrated intraperitoneally (50–200 mg/kg). SAC significantly suppressed the increases of plasma ALT and LDH levels. SAC also attenuated histological liver damage. CCl₄ administration induced lipid peroxidation accompanied by increases in the plasma malondialdehyde and hepatic 4-hydroxy-2-nonenal levels, and SAC dose-dependently attenuated these increases. The hepatic total level of hydroxyoctadecadienoic acid (HODE), a new oxidative stress biomarker, was closely correlated with the amount of liver damage. These results suggest that SAC decreased CCl₄-induced liver injury by attenuation of oxidative stress, and may be a better therapeutic tool for chronic liver disease.     

Inhibiting proteasomal degradation of microsomal triglyceride transfer protein prevents CCl4-induced steatosis

Carbon tetrachloride (CCl(4)) interferes with triglyceride secretion and causes steatosis, fibrosis, and necrosis. In mice, CCl(4) decreased plasma triglyceride-rich lipoproteins, increased cellular lipids, and reduced microsomal triglyceride transfer protein (MTP) without diminishing mRNA levels. Similarly, CCl(4) decreased apoB-lipoprotein production and MTP activity but had no effect on mRNA levels in primary enterocytes and colon carcinoma and hepatoma cells. CCl(4) did not affect MTP synthesis but induced post-translational degradation involving ubiquitinylation and proteasomes in McA-RH7777 cells. By contrast, MTP inhibitor increased cellular lipids without affecting MTP protein. MTP was covalently modified when cells were incubated with (14)CCl(4). This modification was prevented by the inhibition of P450 oxygenases, indicating that CCl(3)(.) generated by these enzymes targets MTP for degradation. To determine whether inhibition of proteolysis could prevent CCl(4) toxicity, mice were fed with CCl(4) with or without lactacystin. Lactacystin increased ubiquitinylated MTP and prevented lipid accumulation in tissues. Thus, CCl(4) induces post-translational degradation without affecting lipid transfer activity, whereas MTP antagonist inhibits lipid transfer activity without causing its destruction. These studies identify MTP as a major target of CCl(4) and its degradation as a novel mechanism involved in the onset of steatosis, suggesting that inhibition of proteolysis may prevent some forms of steatosis.     

RhoG regulates anoikis through a phosphatidylinositol 3-kinase-dependent mechanism

In normal epithelial cells, cell-matrix interaction is required for cell survival and proliferation, whereas disruption of this interaction causes epithelial cells to undergo apoptosis called anoikis. Here we show that the small GTPase RhoG plays an important role in the regulation of anoikis. HeLa cells are capable of anchorage-independent cell growth and acquire resistance to anoikis. We found that RNA interference-mediated knockdown of RhoG promoted anoikis in HeLa cells. Previous studies have shown that RhoG activates Rac1 and induces several cellular functions including promotion of cell migration through its effector ELMO and the ELMO-binding protein Dock180 that function as a Rac-specific guanine nucleotide exchange factor. However, RhoG-induced suppression of anoikis was independent of the ELMO- and Dock180-mediated activation of Rac1. On the other hand, the regulation of anoikis by RhoG required phosphatidylinositol 3-kinase (PI3K) activity, and constitutively active RhoG bound to the PI3K regulatory subunit p85alpha and induced the PI3K-dependent phosphorylation of Akt. Taken together, these results suggest that RhoG protects cells from apoptosis caused by the loss of anchorage through a PI3K-dependent mechanism, independent of its activation of Rac1.     

S-allyl cysteine prevents CCl(4)-induced acute liver injury in rats

Aged garlic extract (AGE) possesses multiple biological activities. We evaluated the protective effect of S-allyl cysteine (SAC), one of the organosulfur compounds of AGE, against carbon tetrachloride (CCl₄)-induced acute liver injury in rats. SAC was administrated intraperitoneally (50-200 mg/kg). SAC significantly suppressed the increases of plasma ALT and LDH levels. SAC also attenuated histological liver damage. CCl₄ administration induced lipid peroxidation accompanied by increases in the plasma malondialdehyde and hepatic 4-hydroxy-2-nonenal levels, and SAC dose-dependently attenuated these increases. The hepatic total level of hydroxyoctadecadienoic acid (HODE), a new oxidative stress biomarker, was closely correlated with the amount of liver damage. These results suggest that SAC decreased CCl₄-induced liver injury by attenuation of oxidative stress, and may be a better therapeutic tool for chronic liver disease.     

Dahuang Zhechong pill attenuates CCl4-induced rat liver fibrosis via the PI3K-Akt signaling pathway

It is well characterized that activated hepatic stellate cells (HSCs) exert critical functions in accelerating the progression of liver fibrosis. Previous studies have indicated that Dahuang Zhechong pill (DHZCP), a traditional Chinese herbal medicine, is capable of inactivating HSCs and thus attenuate the formation of liver fibrosis in rats. However, pharmacological mechanisms of DHZCP in alleviating liver fibrosis remain unclear. This study aims to investigate the antifibrotic role of DHZCP through inhibiting the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) pathway. DHZCP was found to significantly suppresses extracellular matrix formation and immune cell infiltration, thus alleviating liver fibrosis symptoms in the in vivo model. Moreover, DHZCP reduced serum levels of transforming growth factor β1 and tumor necrosis factor-α in rats with liver fibrosis. DHZCP treatment remarkably downregulated protein levels of PI3K and phosphorylated Akt, as well as fibrosis markers. In vitro experiments further demonstrated that DHZCP markedly suppressed HSCs proliferation by downregulating PI3K/Akt, which exerted a synergistic effect with the PI3K inhibitor LY294002. To sum up, our results confirmed that DHZCP exerted an antifibrotic effect in the animal model through inactivating the PI3K/Akt pathway, thus protecting rats from liver injury.     

Enteropathogenic Escherichia coli mediates antiphagocytosis through the inhibition of PI 3-kinase-dependent pathways

The extracellular pathogen enteropathogenic Escherichia coli (EPEC) uses a type III secretion system to inhibit its uptake by macrophages. We show that EPEC antiphagocytosis is independent of the translocated intimin receptor Tir and occurs by preventing F-actin polymerization required for bacterial uptake. EPEC-macrophage contact triggered activation of phosphatidylinositol (PI) 3-kinase, which was subsequently inhibited in a type III secretion-dependent manner. Inhibition of PI 3-kinase significantly reduced uptake of a secretion-deficient mutant, without affecting antiphagocytosis by the wild type, suggesting that EPEC blocks a PI 3-kinase-dependent phagocytic pathway. EPEC specifically inhibited Fc gamma receptor- but not CR3-receptor mediated phagocytosis of opsonized zymosan. We showed that EPEC inhibits PI 3-kinase activity rather than its recruitment to the site of bacterial contact. Phagocytosis of a secretion mutant correlated with the association of PI 3-kinase with tyrosine-phosphorylated proteins, which wild-type EPEC prevented. These results show that EPEC blocks its uptake by inhibiting a PI 3-kinase-mediated pathway, and translocates effectors other than Tir to interfere with actin-driven host cell processes. This constitutes a novel mechanism of phagocytosis avoidance by an extracellular pathogen.     

The protective effect of Ginkgo biloba extract on CCl4-induced hepatic damage

The aim of this study was to evaluate the protective effect of Ginkgo biloba extract on CCl4-induced hepatic damage in rats. Hepatic malondialdehyde, glutathione and hydroxyproline levels and histopathologic alterations in liver specimens were assessed. 200 mg/kg/day Ginkgo biloba extract were given orally to the animals for 10 days, then a single dose of 2 ml/kg b.w. carbon tetrachloride was, administered intraperitoneally. Ginkgo biloba extract treatment reduced hepatic malondialdehyde levels significantly (p < 0.05), but did not alter glutathione (p > 0.05) and hydroxyproline levels (p > 0.05). The light and electron microscopic findings showed that Ginkgo biloba extract limited the CCl4-induced hepatocyte necrosis and atrophy. These results suggest that this extract may protect the hepatocytes from carbon tetrachloride-induced liver injury.     

Glucagon-like peptide-2-stimulated protein synthesis through the PI 3-kinase-dependent Akt-mTOR signaling pathway

Glucagon-like peptide-2 (GLP-2) is a nutrient-responsive neuropeptide that exerts diverse actions in the gastrointestinal tract, including enhancing mucosal cell survival and proliferation. GLP-2 stimulates mucosal growth in vivo with an increased rate of protein synthesis. However, it was unclear whether GLP-2 can directly stimulate protein synthesis. The objective was to test critically whether GLP-2 receptor (GLP-2R) activation directly stimulates protein synthesis through a PI 3-kinase-dependent Akt-mTOR signaling pathway. HEK 293 cells (transfected with human GLP-2R cDNA) were treated with human GLP-2 with/without pretreatment of PI 3-kinase inhibitor (LY-294002) or mTOR inhibitor (rapamycin). Results show that 1) GLP-2 specifically bound to GLP-2R overexpressed in the HEK cells with K(a) = 0.22 nM and B(max) = 321 fmol/μg protein; 2) GLP-2-stimulated protein synthesis was dependent on the amount of GLP-2R cDNA and the dosage of GLP-2 and reached the plateau among 0.2-2 nM GLP-2; 3) GLP-2-stimulated protein synthesis was abolished by the PI 3-kinase inhibitor and mTOR inhibitor; and 4) GLP-2-mediated stimulation of phosphorylation on Akt and mTOR was dependent on the amount of GLP-2R cDNA transfected and the dosage of GLP-2. In addition, GLP-2-mediated action and signaling in regulation of protein synthesis were confirmed in mouse hippocampal neurons (expressing native GLP-2R). GLP-2 directly stimulated protein synthesis of primary cultured neurons in dosage-dependent, PI 3-kinase-dependent, and rapamycin-sensitive manners, which linked with activation of Akt-mTOR signaling pathway as well. We conclude that GLP-2R activation directly stimulates protein synthesis by activating the PI 3-kinase-dependent Akt-mTOR signaling pathway. GLP-2-stimulated protein synthesis may be physiologically relevant to maintaining neuronal long-term potentiation and providing secondary mediators (namely neuropeptides or growth factors).     

Hepatoprotective and antioxidant effects of Morus bombycis Koidzumi on CCl4-induced liver damage

The antioxidant activity and liver protective effect of Morus bombycis Koidzumi were investigated. Aqueous extracts of M. bombycis Koidzumi had higher superoxide radical scavenging activity than other types of extracts. The aqueous extract at a dose of 100 mg/kg showed significant hepatoprotective activity when compared with that of a standard agent. The biochemical results were confirmed by histological observations indicating that M. bombycis Koidzumi extract together with CCl(4) treatment decreased ballooning degeneration. The water extract recovered the CCl(4)-induced liver injury and showed antioxidant effects in assays of FeCl(2)-ascorbic acid-induced lipid peroxidation in rats. Based on these results, we suggest that the hepatoprotective effect of the M. bombycis Koidzumi extract is related to its antioxidative activity.     

16,16-Dimethyl PGE2 and fatty acids protect hepatocytes against CCl4-induced damage

Summary 16,16-Dimethyl PGE₂ (dmPGE₂) has previously been shown to protect the in vivo rat liver against CCl₄-induced damage. These studies were undertaken to determine if this protection could be demonstrated in vitro where factors of absorption, secretion, and blood flow are not present. Primary hepatocyte cultures were established by perfusing rat liver with collagenase. Hepatocytes were plated at a density of 2×10⁴ cells/cm, allowed 90 min to attach, then stabilized in L15 medium for 18 h. Hepatocytes were then challenged with CCl₄ with concomitant exposure to 10⁻⁹ to 10⁻⁵ M dmPGE₂, stearic acid, oleic acid, or ethanol vehicle (0.00001 to 0.1%). After 1 h, challenge was aspirated and cells were stained with 0.04% trypan blue to determine viability. Hepatocytes in the vehicle groups took up more trypan when exposed to CCl₄ than those treated with dmPGE₂, stearic acid, or oleic acid at concentrations of 10⁻⁹ to 10⁻⁷ M. At 0.1% ethanol vehicle protected as well as all other treatments. Protection against CCl₄ by dmPGE₂, stearic, and oleic acids as well as high concentrations of ethanol may occur by altering the metabolism of CCl₄.     

Exenatide prevents high-glucose-induced damage of retinal ganglion cells through a mitochondrial mechanism

Exenatide (exendin-4 analogue) is widely used in clinics and shows a neuroprotective effect. The main objectives of the present study were to prove that retinal ganglion cells (RGC-5) express GLP-1R, to ascertain whether exenatide prevents a high-glucose-induced RGC-5 impairment, to determine the appropriate concentration of exenatide to protect RGC-5 cells, and to explore the neuroprotective mechanisms of exenatide. Immunofluorescence and Western blot analyses demonstrated that RGC-5 cells express GLP-1R. We incubated RGC-5 cells with 25 mM glucose prior to incubation with either 25 mM glucose, 55 mM glucose (high), high glucose plus exenatide or high glucose plus a GLP-1R antagonist. The survival rates of the cells were measured by CCK-8, and cellular injury was detected by electron microscopy. There were statistical differences between the high-glucose group and the control group (P<0.05). Exenatide improved the survival rate of the cells and suppressed changes in the mitochondrial morphology. The optimum concentration of exenatide to protect the RGC-5 cells from high-glucose-induced RGC injury was 0.5 μg/ml, and this protective effect could be inhibited by exendin (9-39). To further study the mechanism underlying the beneficial effects of exenatide, the expression levels of cytochrome c, Bcl-2, Bax and caspase-3 were analysed by Western blot. The present study showed that treatment with exenatide significantly inhibited cytochrome c release and decreased the intracellular expression levels of Bax and caspase-3, whereas Bcl-2 was increased (P<0.05). These results suggested that GLP-1R activation can inhibit the cellular damage that is induced by high glucose. A mitochondrial mechanism might play a key role in the protective effect of exenatide on the RGC-5 cells, and exenatide might be beneficial for patients with diabetic retinopathy.     

Metabolism of glycosaminoglycans in CCl4-induced liver regeneration

The incorporation of [₃₅S]-SO₄ into glycosaminoglycans of liverin vivo and in in liver slices and into the glycosaminoglycans associated with the hepatic plasma membrane of rats at different periods after a heavy dose of CC1₄ have been studied. The incorporation of [35S]-SO4 into total glycosaminoglycans decreased to as low as 40% of the control at 24 h after the administration of CC14 and later on increased reaching a maximum on the 4th day. The amount of [35S]-SO4 incorporation into heparan sulphate was also reduced to about 40% of control at 12–24 h after the onset of injury and increased thereafter reaching a maximum on the 4th day. There was only a partial reduction in the synthesis of chondroitin sulphate in the early stage of injury and then it steadily increased reaching about 3 times the control level on 4–6 days. The [³⁵S]-SO4-incorporation into dermatan sulphate, after a slight initial decrease remained at the control levels. On the 8th day after the CCl₄-induced liver injury, the rate of [³⁵S]-SO₄-incorporation was almost equal to that in normal controls. The incorporation of [³⁵S]-SO₄ into hepatic plasma membrane glycosaminoglycans showed a similar change decreasing to about 35% of control at 24h followed by an increase, reaching normal levels on the 4th day after the administration of CC1₄. About 90% of the plasma membrane glycosaminoglycans was found to be heparan sulphate. The yield of plasma membrane from normal and CCl₄-induced regenerating liver was found to be similar and therefore the results obtained were not due to difference in the yield of the membrane preparation. The data also indicate that there was no difference in the degree of sulphation. The significance of these changes in the metabolism of sulphated glycosaminoglycans particularly plasma membrane heparan sulphate in tissue regeneration has been discussed.     

A novel fluorinated stilbene exerts hepatoprotective properties in CCl(4)-induced acute liver damage

There has been a recently increase in the development of novel stilbene-based compounds with in vitro anti-inflamatory properties. For this study, we synthesized and evaluated the anti-inflammatory properties of 2 fluorinated stilbenes on carbon tetrachloride (CCl?)-induced acute liver damage. To achieve this, CCl? (4 g·kg(-1), per os) was administered to male Wistar rats, followed by either 2-fluoro-4'-methoxystilbene (FME) or 2,3-difluoro-4'-methoxystilbene (DFME) (10 mg·kg(-1), per os). We found that although both of the latter compounds prevented cholestatic damage (γ-glutamyl transpeptidase activity), only DFME showed partial but consistent results in the prevention of necrosis, as assessed by both alanine aminotransferase activity and histological analysis. Since inflammatory responses are mediated by cytokines, mainly tumour necrosis factor α (TNF-α), we used the Western blot technique to determine the action of FME and DFME on the expression level of this cytokine. The observed increase in the level of TNF-α caused by CCl? administration was only prevented by treatment with DFME, in agreement with our biochemical findings. This result was confirmed by measuring interleukin-6 (IL-6) levels, since the expression of this protein depends on the level of TNF-α. In this case, DFME completely blocked the CCl?-induced increase of IL-6. Our results suggest that DFME possesses greater anti-inflammatory properties in vivo than FME. DFME constitutes a possible therapeutic agent for liver disease and could serve as a template for structure optimization.     

Hepatoprotective effect of rooibos tea (Aspalathus linearis) on CCl4-induced liver damage in rats

Hepatoprotective properties of rooibos tea (Aspalathus linearis) were investigated in a rat model of liver injury induced by carbon tetrachloride (CCl(4)). Rooibos tea, like N-acetyl-L-cysteine which was used for the comparison, showed histological regression of steatosis and cirrhosis in the liver tissue with a significant inhibition of the increase of liver tissue concentrations of malondialdehyde, triacylglycerols and cholesterol. Simultaneously, rooibos tea significantly suppressed mainly the increase in plasma activities of aminotransferases (ALT, AST), alkaline phosphatase and billirubin concentrations, which are considered as markers of liver functional state. The antifibrotic effect in the experimental model of hepatic cirrhosis of rats suggests the use of rooibos tea as a plant hepatoprotector in the diet of patients with hepatopathies.     

Hepatoprotective effects of Solanum nigrum Linn extract against CCl(4)-induced oxidative damage in rats

Solanum nigrum L. (SN) is an herbal plant that has been used as hepatoprotective and anti-inflammation agent in Chinese medicine. In this study, the protective effects of water extract of SN (SNE) against liver damage were evaluated in carbon tetrachloride (CCl4)-induced chronic hepatotoxicity in rats. Sprague-Dawley (SD) rats were orally fed with SNE (0.2, 0.5, and 1.0 g kg(-1) bw) along with administration of CCl4 (20% CCl4/corn oil; 0.5 mL kg(-1) bw) for 6 weeks. The results showed that the treatment of SNE significantly lowered the CCl4-induced serum levels of hepatic enzyme markers (GOT, GPT, ALP, and total bilirubin), superoxide and hydroxyl radical. The hepatic content of GSH, and activities and expressions of SOD, GST Al, and GST Mu that were reduced by CCl4 were brought back to control levels by the supplement of SNE. Liver histopathology showed that SNE reduced the incidence of liver lesions including hepatic cells cloudy swelling, lymphocytes infiltration, hepatic necrosis, and fibrous connective tissue proliferation induced by CCl4 in rats. Therefore, the results of this study suggest that SNE could protect liver against the CCl4-induced oxidative damage in rats, and this hepatoprotective effect might be contributed to its modulation on detoxification enzymes and its antioxidant and free radical scavenger effects.     

Diacylglycerol kinase inhibition prevents IL-2-induced G1 to S transition through a phosphatidylinositol-3 kinase-independent mechanism.

Stimulation via IL-2R ligation causes T lymphocytes to transit through the cell cycle. Previous experiments by our group have demonstrated that, in human T cells, IL-2 binding induces phosphatidic acid production through activation of the alpha isoform of diacylglycerol kinase. In this study, using the IL-2-dependent mouse T cell line CTLL-2, we demonstrate that pharmacological inhibition of IL-2-induced diacylglycerol kinase activation is found to block IL-2-induced late G1 to S transition without affecting cell viability. Herein, we demonstrate that diacylglycerol kinase inhibition has a profound effect on the induction of the protooncogenes c-myc, c-fos, and c-raf by IL-2, whereas expression of bcl-2 and bcl-xL are not affected. When the IL-2-regulated cell cycle control checkpoints are examined in detail, we demonstrate that inhibition of diacylglycerol kinase activation prevents IL-2 induction of cyclin D3 without affecting p27 down-regulation. The strict control of cell proliferation exerted by phosphatidic acid through activation of diacylglycerol kinase is independent of other well-characterized IL-2R-derived signals, such as the phosphatidylinositol-3 kinase/Akt pathway, indicating the existence of a different and important mechanism to control cell division.     

Protection against myocardial ischemia/reperfusion injury in TLR4-deficient mice is mediated through a phosphoinositide 3-kinase-dependent mechanism

TLRs play a critical role in the induction of innate and adaptive immunity. However, TLRs have also been reported to mediate the pathophysiology of organ damage following ischemia/reperfusion (I/R) injury. We have reported that TLR4(-/-) mice show decreased myocardial injury following I/R; however, the protective mechanisms have not been elucidated. We examined the role of the PI3K/Akt signaling pathway in TLR4(-/-) cardioprotection following I/R injury. TLR4(-/-) and age-matched wild-type (WT) mice were subjected to myocardial ischemia for 45 min, followed by reperfusion for 4 h. Pharmacologic inhibitors of PI3K (wortmannin or LY294002) were administered 1 h before myocardial I/R. Myocardial infarct size/area at risk was reduced by 51.2% in TLR4(-/-) vs WT mice. Cardiac myocyte apoptosis was also increased in WT vs TLR4(-/-) mice following I/R. Pharmacologic blockade of PI3K abrogated myocardial protection in TLR4(-/-) mice following I/R. Specifically, heart infarct size/area at risk was increased by 98% in wortmannin and 101% in LY294002-treated TLR4(-/-) mice, when compared with control TLR4(-/-) mice. These data indicate that protection against myocardial I/R injury in TLR4(-/-) mice is mediated through a PI3K/Akt-dependent mechanism. The mechanisms by which PI3K/Akt are increased in the TLR4(-/-) myocardium may involve increased phosphorylation/inactivation of myocardial phosphatase and tensin homolog deleted on chromosome 10 as well as increased phosphorylation/inactivation of myocardial glycogen synthase kinase-3beta. These data implicate innate immune signaling pathways in the pathology of acute myocardial I/R injury. These data also suggest that modulation of TLR4/PI3K/Akt-dependent signaling pathways may be a viable strategy for reducing myocardial I/R injury.     

Systemic histopathology of rats with CCl4-induced hepatic cirrhosis

Systemic histopathological examinations were carried out on rats with CCl4-induced hepatic cirrhosis. Moderate congestion in the spleen, prominent oedema in the focal acinar cell degeneration in the pancreas, marked haemorrhage and phagocytosis of haemosiderin by macrophages in the pancreaticoduodenal lymph node, appearance of monocytes bearing haemosiderin-like granules in the pulmonary arteries and cardiac right atrium, and focal segmental glomerulosclerosis were consistently observed in rats with hepatic cirrhosis. In addition, a marked increase in number of target cells and the appearance of a small number of monocytes bearing haemosiderin-like granules were also commonly found in the peripheral blood smears of these animals. These findings are considered to be important in the use of the CCl4-induced model of hepatic cirrhosis in the rat.