The comparative study of the blood clearances of 99mTc-phytate (99mTc-P) and indocyanine green (ICG) was carried out in dogs with hepatic injury induced by carbon tetrachloride (CCl4), and the blood clearance of 99mTc-P or ICG was compared with the levels of serum transaminase and bilirubin. The blood clearances of 99mTc-P and ICG in dogs decreased with increase in doses of CCl4 and with elapsed time after CCl4 administration. The decreases were correspondent to the increase in serum transaminase activity and bilirubin level. The blood clearance test of 99mTc-P in dogs showed a equal degree of sensitivity and a higher degree of accuracy for the acute hepatic dysfunction induced by CCl4 as compared with the blood clearance test of ICG.
To quantify metals in biological samples, we tried to find good conditions for wet-digested mineralization of the samples and for separation of metal ions in chromatography. A 500μl volume of aliquot was transferred to a glass tube, and was evapolated at 100°C for 2 hours. A 5.5 ml volume of a mixture of concentrated nitric acid-70 % perchloric acid (10 : 1, v/v) was added and heated, consecutively, at 80°C for 12 hours, at 140°C for 2 hours, at 180°C for 2 hours, and finally at 190°C for 1 hour to evapolate the residual acids. After addition of 500 μl of 10 mM nitric acid, the metals were extracted by a suspension mixer (32 r.p.m., 1 hour). One hundred μl of the extracted solution was applied to the chromatographic system : cation-exchange column, TSKgel IC-Cation SW (Tosoh Co.) ; eluent, 0.35 M lactic acid-0.35 M sodium lactate (pH 3.0) ; flow rate, 0.7 ml/minute ; column temperature, 30°C. After adding a color-forming reagent (100 mg/l 4-(2-pyridylazo)-resorcinol in 40 g/l Na2CO3 ; flow rate, 0.7ml/minuie) to the effluent, five different metal ions of Cd2+, Co2+, Cu2+, Ni2+ and Zn2+ were detected at 520 nm. The peaks were separated in approximately 25 minutes, and were quantified even at the 1-10 ppb levels. The present procedures were considered to provide simultaneous detection and accurate quantitation of the above five metals in the biological samples.
In order to study the chronic toxicity of 2, 4, 6-tri-tert-butylphenol (TTBP), groups of 40 Slc : Wistar rats of either sex were fed diet containing 0, 30, 100, 300 or 1000 ppm of TTBP for up to 24 months. Hematological, biochemical and histopathological examinations performed periodically revealed slight microcytic anemia, changes in some biochemical parameters relating to liver function and focal necrosis of liver cells following TTBP administration, and these changes observed in females were severer than those in males. No neoplastic responses following TTBP administration were noted. Noticeable changes were not observed in the 30 ppm group throughout the experimental period. Thus, it was concluded that TTBP causes liver injury characterized by focal necrosis with microcytic anemia and elevations of serum phospholipids and cholesterol levels presumably occurring as secondary effects following the liver injury.
Mizoribine (Mz) is an analogue of azathioprine (Az) with less hepatotoxicity, being extensively used as immunosuppressant in place of the latter agent especially in Japan. However, careful comparative studies of mizoribine (Mz), cyclosporine (Cy), and prednisolone (Pr) versus azathioprine (Az), Cy and Pr or Cy and Pr in renal allotranspalnt patients have not been reported. Retrospectively we compared triple therapy with Mz, Cy, and Pr (group I, n=50) to triple therapy with Az, Cy and Pr (group II, n=13) and/or double therapy with Cy and Pr (group III, n=11) in one-haplotype-identical living related renal transplantations performed between Oct. 1984 through March 1989. Initial and maintenance doses of Cy in groups I and II were largely two thirds of those in group III. Patient and graft survival rates at 3 years in each group are 100% and 92% (group I), 100% and 91% (group II), and 91% and 82% (group III). There were no statistical differences in patient and graft survival rates between these three groups. The incidences of miscellaneous complications were the same in the groups. Bone marrow suppression, however, was significantly less in group I than in group II (P<0.005). Cy related nephrotoxicity was apparently less in groups I and II than in group III. Estimated US $5, 000 in a year can be saved by immunosuppressive treatment in a patient of group I as compared to a patient in group III. Therefore, we conclude that triple therapy with Mz, Cy and Pr is superior to those with Az, Cy and Pr, and/or double therapy with Cy and Pr.
As a part of short-term safety assessment of γ-Oryzanol, the genotoxic or the carcinogenic initiation activity was studied in three genetic toxicity tests and the promotion activity was studied in a cell-cell communication inhibitory test. γ-Oryzanol showed the negative response in the bacterial DNA repair test (Rec-assay), the bacterial reverse mutation tests (Ames test) and the rat bone marrow chromosome aberration test. Also, γ-Oryzanol showed the negative response in the metabolic cooperation inhibition test using Chinese hamster V79 cells.