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Biomedical subjects

A Watanabe

Publications and source records attributed to A Watanabe.

At least 865 records · Page 48Linked to original sources
PubMed1985

Determination of free and total 3-methoxy-4-hydroxyphenylethylene glycol in human plasma by high-performance liquid chromatography with electrochemical detection.

A new assay method for the determination of free and total 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) in human plasma is described. MHPG was purified with a Bond Elut PH column followed by ethyl acetate extraction. High-performance liquid chromatography (HPLC) with electrochemical detection was used for separation and detection of MHPG. Total MHPG was measured after enzymatic hydrolysis with sulfatase type H-5. 3-Hydroxy-4-methoxyphenylethylene glycol (iso-MHPG) was used as an internal standard to correct the recovery of extraction. One assay could be completed within 20 min with a short reverse-phase column. This technique is sensitive, reliable and less time-consuming than other HPLC methods. With this method, the plasma values of MHPG in healthy controls were in good agreement with those using gas chromatography-mass spectrometry.

Acetates↗
PubMed1985

Impaired acetaldehyde metabolism in partially hepatectomized rats.

Two-thirds hepatectomy in rats resulted in elevated blood ethanol and acetaldehyde levels as compared to those of sham operated and CCl4-induced toxic injured rats. The acetaldehyde/ethanol ratio increased also. Although the liver mass regenerated within 3 days, ethanol metabolism remained disturbed. Mitochondrial aldehyde dehydrogenase activity was significantly diminished only following partial hepatectomy. The results suggest that abnormal ethanol and especially acetaldehyde metabolism in partially hepatectomized rats is not due simply to reduced liver tissue but to a diminished aldehyde dehydrogenase activity in the remaining tissue.

Acetaldehyde↗
PubMed1985

Excitatory and inhibitory amino acid neurotransmitters and ammonia metabolism in hepatic failure rats.

The molar ratio of excitatory amino acid neurotransmitters (glutamate and aspartate) to inhibitory amino acid neurotransmitters (r-aminobutyric acid, GABA, and glycine) in the brain was diminished in acute hepatic failure rats with hyperammonemia, brain edema, and abnormal electroencephalograms. The ratio was further decreased with a marked elevation of arterial and brain ammonia levels 30 min after ammonium acetate was administered i.p. to hepatic failure rats. A continuous infusion of a branched chain amino acid (BCAA) solution before and after the ammonia loading effectively reversed the ammonia-induced lowering of this ratio; high ammonia contents in the brain were concomitantly decreased. Infusing glutamate instead of the BCAA solution failed to produce similar effects probably because of limited entry of glutamate into the brain. The above results suggest that excitatory and inhibitory amino acid neurotransmitter (glutamate, aspartate, and GABA) levels in the brain of hepatic failure rats might vary with abnormal cerebral ammonia metabolism.

Ammonia↗
PubMed1985

Effects of high hepatic acetaldehyde level following simultaneous administration of ethanol and cyanamide on liver function in rats.

Extremely high concentrations of hepatic acetaldehyde were induced in rats by the intragastric administration of ethanol and cyanamide, an aldehyde dehydrogenase inhibitor; and these high levels were maintained for 4 weeks. Liver function tests, including mitochondrial ornithine carbamoyltransferase (OCT) and GOT activities, were within normal limits, and no increase in either hepatic triglyceride or collagen contents was observed. These results suggest that hepatotoxic effects of ethanol are not derived from the high acetaldehyde levels in the liver.

Acetaldehyde↗
PubMed1985

Accumulation of hepatic collagen following long-term administration of sake to rats.

Sake, a rice wine, induced hepatic collagen accumulation in rats. This was noted after 16 weeks of a liquid diet containing 35% ethanol by caloric content. However, under similar experimental conditions, whiskey and ethanol did not produce any changes. Hepatic collagenase activities in sake-fed rats were slightly, but significantly, higher than in the whiskey group. The central and pericellular liver fibrosis in sake-fed rats was caused possibly by either accelerated collagen synthesis or maturation, exceeding the increased collagen degradation. Mechanisms of enhanced fibrogenesis in sake-fed rats were discussed.

Acetaldehyde↗
PubMed1985

Normalization of low-density lipoprotein levels and disappearance of xanthomas during pregnancy in a woman with heterozygous familial hypercholesterolemia.

Serum lipids and lipoproteins were studied prior to conception, during pregnancy, and after delivery in a woman heterozygous for familial hypercholesterolemia. Prior to conception, serum and low-density lipoprotein (LDL) cholesterol levels were 613 and 528 mg/dL, respectively. At 37-week gestation, serum and LDL cholesterols decreased to the normal levels, 226 and 90 mg/dL, respectively. At two-week postpartum serum and LDL cholesterols returned to the preconception levels, 547 and 427 mg/dL, respectively. At delivery her cutaneous xanthomas almost disappeared. The patient was challenged by ethinyl estradiol of 120 micrograms/d for two months, as a result serum cholesterol decreased from 565 to 385 mg/dL, and LDL cholesterol fell from 460 to 208 mg/dL. During her second pregnancy, serum and LDL cholesterol decreased again significantly. Thus, this case, which showed dramatic reductions of serum and LDL cholesterol levels, may be considered a new variant of heterozygous familial hypercholesterolemia, and the reductions were probably brought about by the action of estrogens, which are known to increase LDL degradation through LDL receptors.

Adult↗
PubMed1985

Effect of various central nervous system-acting drugs on ethanol and acetaldehyde metabolism in rats.

Blood ethanol levels following intravenous ethanol administration were much higher during anesthesia with diethyl ether (ether), phenobarbital and pentobarbital than in unanesthetized control rats. Blood acetaldehyde levels were significantly lower during anesthesia with ether. Ether inhibited alcohol dehydrogenase (ADH) activities in vitro in an uncompetitive fashion; Ki, ether concentration which produced 50% inhibition of NADH formation, was 9.7 mM. Pentobarbital produced slight elevations of ADH activities in vitro and phenobarbital had no effects. Acetaldehyde levels during anesthesia with phenobarbital and pentobarbital were slightly higher than in unanesthetized animals. Phenobarbital and pentobarbital inhibited aldehyde dehydrogenase (ALDH) activities in vitro in a noncompetitive fashion; Ki were 29 and 37 mM, respectively. Ether did not influence ALDH activities in vitro. Thus, pentobarbital was suggested as the most appropriate anesthetic agent in such animal experiments.

Acetaldehyde↗
PubMed1985

A vegetable protein-rich diet for the treatment of liver cirrhosis.

Twelve patients were administered a vegetable protein-rich diet, which was low in methionine and high in the branched-chain amino acid (BCAA) to aromatic amino acid (AAA) molar ratio, and an animal protein-rich diet, high in methionine and low in the BCAA/AAA molar ratio. These diets were administered successively for one week each. Actually ingested amounts of tyrosine and methionine were significantly lower during the feeding of the vegetable protein-rich diet than the animal protein-rich diet. Serum methionine concentrations increased while on the animal protein-rich diet and decreased following the switch to the vegetable protein-rich diet. No other amino acid concentrations were affected. Significant differences were not observed in nitrogen balance or serum protein concentrations.

Adult↗
PubMed1985

Cerebral edema associated with acute hepatic failure.

The clinicopathological findings of cerebral edema were investigated in patients with acute hepatic failure autopsied at Okayama University Hospital between 1970 and 1980 retrospectively. Nine (64%) of 14 hepatic failure cases were found to have cerebral edema during a post-mortem examination of the brain. Clinical features of the patients with cerebral edema were not significantly different from those of the patients without cerebral edema. However, general convulsions were observed more frequently in patients later found to have cerebral edema. Moreover, the length of time from deep coma to death was much shorter in the brain edema cases with cerebral herniation than without herniation.

Acute Disease↗
PubMed1985

Plasma branched chain amino acid abnormalities in sake-treated rats.

Plasma amino acid abnormalities in rats treated with large doses of sake and whisky for 3 days were investigated under adequate nutritional conditions. A significant decrease in plasma branched-chain amino acid (BCAA) levels was observed in sake- but not whisky-treated rats. However, known factors affecting BCAA levels, such as serum insulin and plasma glucagon levels ahd BCAA-metabolizing enzyme (BCAA transaminase and branched chain alpha-ketoacid dehydrogenase) activities in the liver and skeletal muscle, were not significantly altered in the sake group. Furthermore, ethanol-metabolizing enzyme (alcohol and aldehyde dehydrogenases and the microsomal ethanol-oxidizing system) activities in the liver were not altered in the sake group. Other mechanisms need to be considered for explaining the diminished levels of plasma BCAA in sake-treated rats.

Alcoholic Beverages↗
PubMed1985

Nutritional treatment of liver cirrhosis by branched-chain amino acid-enriched nutrient mixture.

The effects of branched-chain amino acid (BCAA)-enriched nutrient mixture (nutrient-mixture) on the nitrogen metabolism and nutritional state were clinically investigated in 10 patients with liver cirrhosis. Nutrient-mixture-supplemented diet was prepared by adding 150 g nutrient-mixture daily to low-protein diet, and comparisons were made with a regular diet (control diet). Each diet supplied 2,100 kcal energy and 80 g protein per day. Patients were given control diet for 2 weeks and thereafter treated successively with nutrient-mixture-supplemented and control diet each for 2 weeks. Nitrogen balance improvement and positive balance were observed during the feeding of nutrient-mixture-supplemented diet. The composition of nitrogen compounds in urine and the fecal nitrogen excretion did not alter during the test period. Plasma aromatic amino acid (AAA) concentrations decreased and BCAA/AAA molar ratios increased significantly during the 1st and 2nd week of nutrient-mixture-supplemented diet administration. Plasma methionine concentration also decreased in the 1st week. Plasma pre-albumin levels rose significantly during the 1st and 2nd week of nutrient-mixture-supplemented diet administration, and the number connection test improved significantly following the supplemented diet. These results suggest that the use of nutrient-mixture in the nutritional treatment of liver cirrhosis had no deleterious effects on nitrogen metabolism and is useful for the improvement of plasma amino acid imbalance and protein-energy malnutrition.

Adult↗