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It is reasonable to presume that the metabolism of the steroid hormones in the liver may play an important role in elucidating their physiologic significance. Although there are many methods by which the intrahepatic metabolism of the steroid hormones can be evaluated, little has been reported on a method to elucidate simultaneously such dynamic factors as metabolic rate, quantities passing through the liver, structural change, conjugation and the like. In this paper, comparative studies on the methods for the investigation of steroid hormone metabolism in the liver were carried out. These include batch incubation, dialysis, continuous flow perfusion, portal vein injection and the "tissue column method" which was newly designed in order to search for the dynamic factors described above in a simple system, simultaneously. In the "tissue column method" studied here, cell suspension of the rabbit liver mixed with Sephadex G 75 gel (4:1 in volume) was packed at the height of 4 cm in a glass column (internal diameter; 1.5 cm). After an isotopically labelled steroid was placed on the tissue column, this column was perfused with oxygenated extracellular fluid (pH 7.4), keeping the perfusion system at 37 degrees C. The perfusion was continued for 60 min. and the perfusate was collected in 5 fractions. Flow rate was kept at 2 ml/min. When the perfusion was stopped, the cells were rapidly homogenized. The concentrations of the radioactivity in each perfusate, and in the final cells were measured. The amount of entry into the liver cells were calculated. The compounds in the perfusate and in the cells were separated by alumina column chromatography for analyzing the metabolites. Based on these experiments, the following conclusions were drawn; 1) Usual methods with liver slices and homogenates can clarify only the metabolic pathway. 2) To examine the amount of entry of steroids into the liver, portal vein injection as well as the "tissue column method" are preferable to the methods of dialysis and batch incubation. It seemed probable that the entry of steroids into the liver might not be explained simply on the basis of passive transfusion. 3) Incubation of slices and homogenate are of great advantage in studying the metabolic transformation in a specific organ. However, portal vein injection as well as the "tissue column method" are much more preferable to investigate the conjugation of steroids in the liver. 4) Continuous flow perfusion reported by Elrio Gurpide is suitable to examine the metabolism and the entry of steroids in a specific organ, but it is disadvantageous for investigating the conjugation of steroids because of its low production rate of conjugated steroids. 5) The portal injection method is intricate, troublesome and expensive, but this method provides a situation similar to in vivo circumstances...

Chimeric mouse with humanized liver is an experimental animal which is produced by transplanting normal human hepatocytes into a host mouse having both of immunodeficient and liver-injured characters. PXB-mouse ® , which is developed and supplied by PhoenixBio group, is produced by utilizing cDNA-uPA/SCID mouse as a host animal and has a humanized liver containing over 70% of human hepatocytes. It has been utilized in the research fields of drug metabolism such as investigation of human-specific metabolites and pharmacokinetics, prediction of human DILI and development of anti-viral hepatitis drugs. Furthermore, it is expected that PXB-mouse will be valuable for the development of drugs of new modalities as the emerging technologies such as oligonucleotide medicine and gene therapy. Because it has an organ which consists almost entirely of human cells PXB-mouse is expected to be used in validation of efficacy or prediction of off-target effect caused by human specific nucleotide sequence. This paper introduces the character of PXB-mouse focusing on the successful achievements in these research fields.

MR imaging, which is able to evaluate T1- and T2-relaxation time, fat, hemorrhage, metal deposition, blood flow, perfusion, diffusion, and so on, has offered more information for the diagnosis of diffuse and focal hepatic diseases than CT. The spoiled-GRE sequence with high contrast resolution and ease of the aimed contrast capture derived from the k-space property, with the use of a phased-array multicoil, have remarkably increased the value of gadolinium-enhanced dynamic MR diagnosis of the liver. In recent years, the clinical use of ferumoxide has begun, and issues concerning the superiority or inferiority and combination of contrast media are being debated. This paper describes the value, role, and clinical practice of unenhanced, gadolinium-enhanced, and ferumoxide-enhanced MR imaging of the liver based on knowledge obtained in our institution, with some reference to the literature.

The risk of atherosclerosis has been known to be inversely correlated with the plasma concentration of high-density lipoprotein (HDL)-cholesterol, and we now know HDL plays a protective role against atherosclerosis. The most important mechanism, by which HDL could exert their anti-atherogenic role, is certainly the removal of excess cholesterol from peripheral cells and its transport to the liver, a process commonly called "reverse cholesterol transport system". In this system, many proteins are involved, i.e., ABC1, LCAT, CETP, HTGL and SR-BI. Abnormalities of these proteins reduce the efficacy of the system, and cause abnormalities of HDL and atherosclerosis. In this paper, we review the recent findings on the molecular mechanism of reverse cholesterol transport system, and then discuss hypo- and hyperalphalipoproteinemia, which are caused by genetic abnormalities of the key players.

We have reported that a 54 kDa protein in rat liver cytosol is highly inducible by treatment with 3,3',4,4',5-pentachlorobiphenyl (PenCB) or 3-methylcholanthrene (MC) using SDS-polyacrylamide gel electrophoresis. Internal amino acid sequences of this protein in the rat liver were highly homologous to those of selenium binding protein (SeBP) or acetaminophen binding protein (APBP) in mouse liver cytosol. In this paper, the purification and characterization of this protein were demonstrated. MC was given at a dose of 20 mg/kg for 3 consecutive days. The liver cytosolic 54 kDa protein was purified twice from the MC-treated male Wistar rats by Rotofore Cell procedure to apparent single on SDS-polyacrylamide gel electrophoresis, and the rabbit antiserum against this protein was obtained. Male Wistar rats were given PenCB in corn oil at a single dose of 25 mg/kg i.p. The liver cytosol was prepared on the 5th day after the treatment and subjected to immunoblot analysis. The 54 kDa protein was markedly induced in the liver cytosol of PenCB-treated rats. Immunoblot analysis after two-dimensional gel electrophoresis suggested that there could be isoforms of 54 kDa protein. The induction of the 54 kDa protein with PenCB was assumed to be mediated through Ah-receptor. The physiological role of the 54 kDa protein was discussed together with SeBP and APBP, the role of which has not yet been elucidated.

Apoptosis is known to be induced by radiation. However, the correlation between radiation-induced apoptosis and radiation injury in tumors in vivo has been unclear. In this paper, we report the study of apoptosis induced by whole-body irradiation using an immunohistochemical technique to detect DNA fragmentation in murine liver. A dose of 7 Gy was employed as LD50/30. DNA fragmentation was observed 30 min after radiation, and it peaked between 1 and 6 hours. DNA fragmentation could be detected 48 hours after radiation in capillary endothelium. This study was able to reveal the development of radiation-induced apoptosis in the liver by detecting DNA fragmentation in situ.

In the intrahepatic lymphocyte fraction (IHL) of mice whose livers have been perfused by Ca+2 and Mg+2 free Hank's balance salt solution, flow cytometric analysis reveals various cells similar to those found in the spleen (CD3+ cell, CD4+ cell, CD8+ cell, alpha beta TCR+ cell, gamma delta TCR+ cell, Thy1.2+ cell, B220+ cell and asialo-Gm1+ cell). The cytotoxic activity against YAC-1 cells in IHL is significantly higher than that in spleen cells. Furthermore, IHL has cytolytic activity against syngeneic thymoma BW5147 cells which is not found in spleen cells. Both cytotoxic activities of IHL are greatly weakened by the pretreatment of IHL with anti asialo-Gm1 Ab and rabbit complement. During liver regeneration after a partial hepatectomy, the percentages of lymphocyte subsets of IHL such as alpha beta TCR+ cells, gamma delta TCR+ cells and asialo-Gm1+ cells transiently increase 2 days after the partial hepatectomy and their cytotoxic activities against YAC-1 and BW5147 cells also reach a peak at that time. It is well known that the peak of mitotic index in regenerating parenchymal liver cells peaks 2 days after a partial hepatectomy and that the number of Pit cells peaks 10 to 14 days after. Compared with the time for reaching the highest mitotic index in regenerating parenchymal liver cells, the proliferation of Pit cells comes very late. It has not been clear which proliferation process in parenchymal liver cells is suppressed by activated Pit cells. Our findings in this paper reveal that the percentages and the cytotoxic activities of asialo-Gm1+ cells in IHL reach their peak 2 days after an operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Liver has enough functional capacity and regeneration ability. Liver parenchymal cells are usually stable, and it is thought being at stage of Go in cell cycle. But liver cells are easily into progressive stage and the liver recovers its functions and volume after partial hepatectomy or liver injury. Usually the studies of liver regeneration are done by studying control of growth of isolated hepatocytes in primary culture in vitro, and by pathological considerations of experimental injured models of liver in vivo. In this paper, we considered known several hepatotrophic factors including our experimental results, and regeneration mechanisms by noticing appearance of albumin positive hepatocytes in injured Nagase analbuminemic rat (NAR).

For the study of immunological phenomena peculiar to liver transplantation, it would be important to know well hematolymphoid system in the liver. In this paper, we report the restoring mechanism of hemopoiesis in the murine regenerating liver. 1) We found hemopoietic stem cells (HSC) and wheat germ agglutinin positive cells (WAG-PC) in both fractions of peripheral blood lymphocytes (PBL) and intrahepatic lymphocytes (IHL) from untreated C3H/He mice. The numbers of HSC and WGA-PC in each fraction gradually increased after partial hepatectomy. This change was remarkable in the population of IHL, associated more strongly with the liver. Colonies, which were generated from IHL in a fibrin clot culture system, are mainly composed of granulocytes, macrophages and mast cells. 2) We found colony-stimulating activity not only in the culture supernatant of normal nonparenchymal liver cells but in that of normal parenchymal liver cells. Furthermore, we clarified that one of colony-stimulating factors in both culture supernatants is GM-CSF. This result suggests parenchymal liver cells also release cytokines such as GM-CSF. These facts show that hematolymphoid system in the liver is a complicated network, composed of parenchymal liver cells, nonparenchymal liver cells, hemopoietic stem cells, and other cell populations.

Liver cells have many functions, and one of which is a production of plasma proteins. Therefore, studies on synthesis and production of plasma proteins from hepatocytes are very important for the recognition of various hepatic dysfunctions, clinically. Of late years, a lot of the complex mechanism of protein synthesis and--secretion was elucidated by using a technique of liver cell culture, for example, primary monolayer culture by freshly isolated hepatocytes and cloned cell culture derived from hepatocellular carcinoma. This paper described the results of our observations and other researchers, and then discussed the point of production of human major plasma proteins using the above culture methods, such as albumin, alpha-fetoprotein and transferrin. Furthermore, we showed statistically that half of twenty-six human hepatoma cell lines established until 1988 in Japan, had already lost their secretory potencies of major plasma proteins in vitro.

At this present, enzyme perfusion method is a routine technique to isolate hepatocytes from rat liver for the physiological and pathological experiments. This study described a way of the classification of freshly isolated hepatocytes. First of all, the hepatocytes were fractionated with parenchymal and non-parenchymal cells by low speed centrifugation. And then these cells were subfractionated with a newly developed Percoll linear density gradient method. The fractionated parenchymal cells were divided with cells of periportal and centrilobular areas, respectively. Furthermore, their characteristics were confirmed functionally and morphologically. Non-parenchymal cells (NPC) include Kupffer cells, endothelial cells and fat storing cells (FSC, Ito cells). These isolated NPC are fractionated with a method as mentioned above or centrifugal alutriation method. In this paper, fractionation and classification of Kupffer cells and FSC were discussed with the measurement of fluorescent intensity of vitamin A and the morphological observation of cytoskeleton in culture. Especially, transport of vitamin A into FSC were detected autoradiographically.

The first paper describing ultrasonically guided biopsy of the kidney was reported by Berlyne in 1961. The next important development was the production by Holm and Goldberg in 1972 of a special pilot transducer with a central cannula through which a fine needle could be introduced. The present author reported the definitive diagnosis of pancreatic carcinoma with percutaneous aspiration biopsy using contact compound scanning methods in 1977. A new para real time method has been recently the developed to allow needle puncture we through the pancreas, liver and gallbladder. The needles and commonly used have been 22 and 23-gauge and 15 or 20 cm in length. Cytological diagnosis of adenocarcinoma of the pancreas was made with an accuracy of 40 cases out of 45 (89%). That for the liver and gallbladder was 100%. On inserting the needle into the gallbladder for cytological examination, a biochemical analysis of bile juice , CEA and LDH, was performed, as for cases of pancreatic cyst. In gallbladder carcinoma, LDH and CEA showed significantly higher levels than in benign mass lesions. The merits of ultrasonic real time guidance for puncture technique are safety, ability of hitting a small target accurately, short time requirement, harmlessness and ease of use at the bedside.

The role of CT in the diagnosis of fatty liver is well established. CT has been proved to be a useful noninvasive tool for the demonstration of fatty infiltration of the liver. The characteristic finding is a diffuse decrease in the attenuation within the liver compared with that of the spleen. Commonly, fatty infiltration of the liver is generalized and both CT scans and sonograms can easily demonstrate changes related to this condition. Sometimes, fatty infiltration of the liver is focal and occasionally, it is generalized with focal sparing of the normal liver tissue creating some problems in the diagnosis. Recently, some reports have mentioned the appearance of a focal sparing area in the generalized fatty liver. We often found a high attenuation region around the gallbladder bed in the fatty liver patients on CT examination. There appears to be some relationship between the high density around the gallbladder area and the fatty liver. A retrospective study was undertaken to evaluate the relationship. In this paper, we presented the CT scans of 57 fatty liver cases and compared them with the CT scans of 50 normal patients to discuss the possible cause of the phenomenon and its usage in the diagnosis of the fatty liver.

O,p'-DDD is used for the treatment of adrenocortical carcinoma and Cushing's disease. The inhibitory effect of this drug on the adrenal steroid biosynthesis has been described by many authors, but there are very few reports about the sites of action of this drug on adrenal steroid synthesis. This paper presents in vitro studies on adrenal steroidogenesis and hepatic steroid metabolism. The effects of o,p'-DDD on adrenal 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), 11 beta-hydroxylase (11 beta-OHlase) and 18-hydroxylase (18-OHlase) were examined in vitro using mitochondrial and microsomal fractions prepared by standard centrifugation procedures from the homogenate of bovine adrenal cortices. The concentrations of o,p'-DDD inducing 50% inhibition of 3 beta-HSD, 11 beta-OHlase and 18-OHlase were 8 X 10(-6) M, 1 X 10(-5) M and 3 X 10(-6) M, respectively. This study clearly demonstrates the marked inhibitory effects of o,p'-DDD on 3 beta-HSD in vitro, which was not described previously. The inhibitory effects of o,p'-DDD on these 3 enzymes were diminished by an addition of 0.05 approximately 0.5 mM of cofactor (NADPH or NAD). The results indicate that o,p'-DDD may reduce NADPH or NAD utilization, resulting in the inhibition of steroidogenesis. The effects of o,p'-DDD on hepatic 5 beta-reductase were examined in vitro using rat liver homogenate. O,p'-DDD inhibits 5 beta-reductase, resulting in the decrease of conversion of cortisol to dihydrocortisol and tetrahydrocortisol at the concentration of 10(-3) M.