Classical pathology demonstrated that fluorescent lipofuscin granules developed in the aged cells. They were believed to be waste-products of subcellular components during lipid peroxidation. They were composed of lipids, proteins and melanin-like pigments. Recent works by Tappel and his associates demonstrated that age-related fluorescent pigments increased with lipid peroxidation of tissues and were extracted with organic solvents. Tappel et al. suggested that the fluorophore of the pigments was the conjugated Schiff bases between primary amines and malonaldehyde. Our current studies suggested that malonaldehyde did not participate in the formation of the pigments although mild reaction of primary amines and malonaldehyde afforded highly fluorescent 1, 4-dihydropyridine-3, 5-dicarbaldehydes (I and II). Mechanisms of the formation of the fluorophore of the pigments are not obvious. While physiological role of lipofuscin granules or the age-related fluorescent pigments is obscure, it may be important to elucidate mechanisms of lipid peroxidation to produce such fluorophores in biological systems.

抄録全体を表示

The acute and subacute effects of exposure of rats to nitrogen dioxide (NO₂) at low levels on lung, liver and red blood cells were examined biochemically and cytologically. In addition, influences of nitrate and nitrite, chemical intermediates of inhaled NO₂, on red blood cells and hepatic microsomes were examined in vitro to clarify the mechanisms responsible for in vivo effects of NO₂. The biological significance of responses to NO₂ was discussed with respect to physiological adaptation to low levels of NO₂. I. In the lung, a metabolic enhancement developed in several days of NO₂ inhalation. This was followed by an increase in alveolar cells such as macrophages and Type II epithelial cells. These results suggest that epithelial cells increase as a response compensating degeneration of lung cells produced by NO₂ inhalation. II. In the blood, an initial response to NO₂ inhalation was an increase in younger red blood cells. This increment seems to occur as compensation for accelerated aging of red blood cells presumably induced by NO₂ inhalation. Some membrane constituents of red blood cells were decreased initially by NO₂ inhalation. This decrement was due to an increasing level of blood nitrate produced by NO₂ inhalation. III. In the lung and liver, NO₂ inhalation periodically decreased the components of microsomal drugmetabolizing systems and mitochondrial respiratory system. These periodic alterations appear to be a reflex of degeneration of membranous components and subsequent stimulation of biosynthesis. It is also suggested that hepatic microsomal components decrease due to a reaction of blood nitrate increased by NO₂ inhalation.

抄録全体を表示

Di 2-ethylhexyl phthalate (DEHP), mono 2-ethylhexyl phthalate (MEHP), and phthalic acid (PA) in human serum or plasma were determined by high performance liquid chromatography and serum or plasma pretreatment methods were also studied. We determined these compounds in blood products and studied what amount of these compounds in flexible bags were migrated into blood products and studied whether MEHP and PA in blood products were produced by the enzymatic action to DEHP. From the comparison of the amount of these compounds in blood products and the amount in flexible bag, it was clarified that MEHP and PA was produced by the action of lipase and esterase to DEHP. The action of esterase was greater than that of lipase and the pathway of MEHP to PA was a rate determining step of DEHP hydrolysis.

抄録全体を表示

The present work was carried out in order to characterize the glutathione S-transferase involved in the detoxication of Sumithion and Malathion. Rat liver 20000×g supernatant fraction was chromatographed on DEAE- or CM-cellulose column. All the fractions were monitored for enzyme activity toward both pesticides by thin-layer chromatodensitometry after separation of S-methylglutathione on microcolumns of activated carbon (7 mm by 7 mmφ). Glutathione S-transferase B was found to be mainly responsible for the formation of S-methylglutathione from both pesticides, though the activity patterns were a little different. Ligandin, unlike glutathione S-transferase B, was strongly induced in male and female rats by administration of phenobarbital and was also partly responsible for the formation of S-methylglutathione. However, the activity of Ligandin was significantly inhibited by sebacic acid. A DEAE-cellulose column, pH 8.0, was found to retain small amounts of glutathione S-transferases capable of catalyzing the formation of S-methylglutathione from both pesticides.

抄録全体を表示

The role of metallothionein (MT) in the metabolism of excess zinc (Zn) was studied by the use of mice and the following results were obtained. 1. By the combined use of cycloheximide (0-150 mg/kg, i.p.) and Zn (50 mg/kg, s.c.), after 6 h the concentrations of MT in the liver, kidney, small intestine and pancreas induced by Zn decreased with an increase in the amounts of cycloheximide administered. In the liver and small intestine a strong positive corelation was detected between MT and Zn concentrations. 2. The combined use of cycloheximide (0-200 mg/kg, i.p.) and Zn (50 mg/kg, s.c.), a weak negative corelation was found (p<0.05) after 6 h between MT and zinc concentrations in the liver and zinc concentration in the plasma. 3. The concentrations of MT and Zn in the organs 2, 4 and 5 d after the administration of Zn (20 mg/kg, s.c.) were measured and a strong positive correlation (p<0.01) was detected between both concentration in the liver, kidney and small intestine. The above results indicate that MT takes part in the metabolism of zinc in vivo.

抄録全体を表示

The effect of wavelength on the photochemical decomposition of dodecylbenzenesulfonate (LAS) and the decomposition process were investigated. When LAS in water was subjected to monochromatic irradiation between 200 and 700 nm from a spectroirradiator equipped with a Xe arc lamp, the largest decomposition rate was observed at 215 nm. Thus a low-pressure mercury lamp providing radiation mainly in the lower ultraviolet (UV) range was chosen as a light source for the photochemical reaction. LAS in various kinds of water samples, e.g., city sewage, treated sewage water, river water, sea water and others, was found to be rapidly decomposed by irradiation with the light source and there was little difference among water samples. Since formaldehyde and formic acid were identified among the photochemically decomposed products of LAS, it is suggested that LAS is photochemically decomposed through formaldehyde and formic acid.

抄録全体を表示

At 18 h after the sham operation or adrenalectomy in male Wistar rats, a low molecular weight (about 10000 daltons) zinc-thionein was observed in the hepatic 105000g soluble fraction on a Sephadex G-75 gel filtration column. The zinc-thionein level returned nearly to the control level 5 d after both operations. In the sham-operated or adrenalectomized rats at 5 d after the operation, a single injection of lead acetate or cadmium chloride at 18 h prior to sacrifice clearly induced the zinc-thionein. On the other hand, zinc content in the serum decreased markedly at 18 h after adrenalectomy. A single administration of lead and cadmium immediately or 4 d after the sham operation or adrenalectomy significantly reduced zinc content in the serum. Total zinc content in the liver was increased by the administration of metals when compared to that of the control. However, the distribution ratio of zinc content in subcellular fractions, namely 600 g ppt, mitochondria, microsome, and 105000g soluble fraction, was similar to that in the control and metal treated rats. Our results in adrenalectomized rats suggest that the induction mechanism of lead-indued zincthionein is distinct from that of adrenal related induced metallothionein.

抄録全体を表示

A high performance liquid chromatographic (HPLC) method was developed for determining propyl gallate (PG) in cosmetic lotions and creams. The sample is extracted with ethyl acetate, and the extract is cleaned up on a florisil column. PG in the purified extract is determined by reverse phase HPLC on a octadecylsilated silica column using a mobile phase of acetonitrile-water with 5% acetic acid, UV detector (275 nm) for the detection. Recoveries of PG from cosmetic samples spiked at 0.005 and 0.001% leveles were 96.2-98.0%, and the coefficients of variation were within 2.71-3.81%.

抄録全体を表示