Acta Medica Okayama volume38 issue5

Carbon tetrachloride (CCl4)-induced hepatotoxicity was potentiated by pretreatment with beta-phenethyl alcohol, abundantly present in sake. The injury was determined by serum GPT levels and histological examination. Similar results were observed in ethanol- and phenobarbital-pretreated rats. Acetaminophen-induced hepatotoxicity was not accentuated by beta-phenethyl alcohol or ethanol pretreatment. The activities of liver microsomal enzymes, such as cytochrome P-450, cytochrome b5 reductase, aniline hydroxylase and aminopyrine demethylase, were not altered in beta-phenethyl alcohol-pretreated rats. Thus, CCl4-induced hepatotoxicity potentiation by beta-phenethyl alcohol administration is postulated to be due to a mechanism other than increased free radical generation.

The prevention of hepatic encephalopathy by the intravenous infusion of a branched chain amino acid (BCAA)-enriched solution was investigated in methionine and ammonium acetate-treated rats whose liver was already injured with carbon tetrachloride. A BCAA-enriched solution protected the rats from entering a coma. The brain BCAA contents became higher, and the brain methionine and tyrosine levels and the ratio of glutamine to glutamic acid in the brain diminished after administering the BCAA-enriched solution.

Ferrous chloride solution was injected unilaterally into the sensorimotor cortex of rats to induce a chronic epileptic focus. Accumulation of cyclic AMP elicited by depolarizing agents was determined in slices from different cortical areas of rats 30-60 days after the injection. In anterior cortical areas which include the sensorimotor cortex, the cyclic AMP accumulation elicited by ouabain or a high concentration of potassium ion was greater in electrographic spike activity on the dominant side than on the other. In posterior cortical areas, no difference in cyclic AMP accumulation was detected. The regional difference in the depolarization-elicited accumulation of cyclic AMP is discussed with regard to the process of epileptic focus.

L-Cysteine (5.0 mmol per kg of body weight) was intraperitoneally injected into rats fed a 25% casein or 5% casein diet. Concentrations of acidic and neutral amino acids in various tissues were determined 2 h later. In the rats fed the 25% casein diet there was a tendency for tissue amino acid and glutathione levels to be slightly lower than controls. In the 5% casein diet group, however, concentrations of tissue amino acids and glutathione generally increased after L-cysteine administration. S-(2-Hydroxy-2-carboxyethylthio)cysteine (HCETC,3-mercaptolactate-cysteine disulfide), though in trace amounts, was detected in kidney and blood plasma in the 5% casein diet group. Increases in cysteine-glutathione disulfide in liver, kidney and erythrocytes in the 5% casein diet group were considerable. These results indicate that L-cysteine was rapidly metabolized in the 25% casein diet group through the oxidative pathway, while in the 5% casein diet group, in which liver cysteine dioxygenase activity is supposed to be quite low, the oxidative metabolism of L-cysteine decreased and part of the L-cysteine was metabolized through the transaminative pathway. Administration of 15.0 mmol L-cysteine per kg of body weight to rats fed the 25% casein diet resulted in an increase in cysteine-glutathione disulfide in liver, kidney and erythrocytes, and the appearance of HCETC in blood plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

<p>Murine sarcoma virus, CS-Moloney substrain, was inoculated intracranially into 2 litters of newborn Syrian hamsters within 24 h of birth. Seven of 12 hamsters which survived more than 30 days developed brain tumors in the cerebral cortex 104 to 153 days, 139 days on the average, after the virus inoculation. The tumors consisted of spindle-shaped, round or polygonal astrocytes which showed a positive reaction for glial fibrillary acidic protein by the immunoperoxidase method.</p>

The influence of surgical stress on the local graft-versus-host reaction (GVHR) in F1 mice was studied. Skin incision 1 day prior to injection of parental spleen cells produced impairment of popliteal lymph node enlargement; however, this effect was not observed when GVHR was induced 3 and 5 days after operation. Strong GVHR suppressive activity of spleen cells was observed three hours after leg amputation before a decrease in thymus weight became evident. The GVHR suppressive activity declined by six hours later, but a second peak of 60% inhibition was observed after 24 h. This suppressive activity completely disappeared by treatment with anti-Thy 1.2 and complement. This shows that the GVHR is suppressed by surgical stress, and that this suppression is due to suppressor T lymphocytes.

Using the technique of somatic cell fusion, we produced monoclonal antibodies to collagenase-digested human glomerular basement membrane (GBM). Fourteen monoclonal antibodies which reacted with normal human kidney in indirect immunofluorescence (IIF) studies were produced. An analysis of the binding patterns indicated that the antigens recognized could be divided into six broad groups. Monoclonal antibody B3-H10 (Group 1) reacted with only GBM in a fine granular pattern. A5-B12 and B5-C2 (Group 2) reacted with GBM and peritubular capillary in a linear pattern. B2-A12 (Group 3) reacted with only epithelial cells. Al-C9 and A4-E2 (Group 4) showed a mesangial pattern in glomerulus and a lineal pattern in tubular basement membrane (TBM), Bowman's capsule and peritubular capillary. A1-E1, A1-E11, A2-E6, A3-B6, A4-F8 and B5-H2 (Group 5) recognized determinants common to GBM, TBM, Bowman's capsule and/or peritubular capillary. A3-F1 and B5-E10 (Group 6) reacted with TBM and Bowman's capsule. The staining pattern of B3-H10 (Group 1) was characteristic because it was not linear, but finely granular along the GBM. The staining pattern of B2-A12 (Group 3) was also characteristic because only epithelial cells were stained, and processes of epithelial cells were observed as fine fibrils. To the best of our knowledge, these two types of monoclonal antibodies have not been reported previously.

A single injection of ferric nitrilotriacetate (Fe3+-NTA) caused a transitory increase in plasma immunoreactive insulin (IRI) and plasma immunoreactive glucagon (IRG) in rats. They reached maximum levels at 2 days after injection and returned to the normal range at 10 days. At 2 days after Fe3+-NTA injection, blood glucose level was normal but the glucose tolerance test (GTT) was impaired. There was a further increase in plasma IRI level and IRG level was suppressed after glucose loading. At 10 days after Fe3+-NTA injection, glucose tolerance was normal and IRI also returned to the normal range. No degenerative changes were found on H.E.-stained rat pancreatic tissue sections after Fe3+-NTA injection. Histochemical staining, however, showed a reduction in beta-granules and heavy metals (Timm's granules) from islet cells in the central area of the rat pancreatic islet 1 to 3 days after injection of Fe3+-NTA. The fading remained in some islets even at 10 days after injection, but by then the beta-granule distribution was restored in most islet cells. The results indicate a single Fe3+-NTA injection induced transitory instability of the pancreatic islet beta-cell granules and the glucose intolerance with a hyperresponse of IRI.

Seventy-one cases of bronchial asthma were classified into three types: bronchospasm, bronchospasm-hypersecretion and bronchiolar obstruction types. The characteristics of each type were studied in relation to patient age and age at onset of the disease. In the 71 subjects studied, the most frequent type was the bronchospasm type followed by the bronchospasm-hypersecretion type and bronchiolar obstruction type. Intractable asthma was most frequently observed in the bronchiolar obstruction type and least in the bronchospasm type. Most of the patients under 50 years of age showed the bronchospasm type. The bronchospasm-hypersecretion type was characteristically accompanied by blood eosinophilia when the patient age was under 50 years. In the bronchospasm-hypersecretion type, the incidence of intractable asthma was high in patients under 50 years of age, but not remarkable in those over 50. A large proportion of the patients over 50 years of age were of the bronchiolar obstruction type. There was no difference in the incidence of intractable asthma between the two groups classified by age at onset.

A modified method of passive immune hemolysis (PIH) was applied to the quantitative assay of heat-labile enterotoxin (LT) produced by enterotoxigenic Escherichia coli. The method enabled the measurement of 0.2 to 1.2 ng LT. The production of LT by enterotoxigenic E. coli under various conditions was analyzed using the modified method. LT production was intense during the logarithmic growth phase and decreased during the stationary growth phase. Lincomycin (50 to 100 micrograms/ml) affected cell growth slightly, but enhanced production of LT until the late-stationary growth phase. About 90% of the LT produced was retained in the cell, and the rest was excreted into the culture medium. The initial pH of the culture medium affected LT production. Alkaline pH enhanced LT production, though growth was depressed. Aeration enhanced both growth and LT production.