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M Miyazaki

Publications and source records attributed to M Miyazaki.

At least 1,063 records · Page 59Linked to original sources
PubMed1977

Catabolism of alpha-fetoprotein in carbon tetrachloride-injured rats.

The rate of alpha-fetoprotein (AFP) catabolism in carbon tetrachloride (CCl4)-treated rats was estimated to be essentially the same as that found in control adult and young rats. The blockade of the reticuloendothelial system by carbon particle resulted in slightly shorter t1/2 values of AFP. The amount of AFP synthesized pet day in CCl4-treated rats was theoretically calculated to be nearly 10-fold increase over that in control rats. Thus, the elevation of serum AFP concentrations in CCl4-treated rats is derived from the increased synthesis of AFP by injured liver.

Animals↗
PubMed1977

Renin inhibitory effect of 2-[4-(4'-chlorophenoxy)phenoxyacetylamino]-ethylphosphorylethanolamine (PE-104) in vitro and in vivo.

The renin inhibitory activity of 2-[4-(4'-chlorophenoxy)phenoxyacetylamino]ethylphosphorylethanolamine (PE-104) was examined in vitro and in vivo. PE-104 inhibited the reaction between dog renal renin and homologous plasma angiotensinogen. The Ki value was 2 mM and the inhibitory mode was competitive and reversible. Data concerning the relationship between renin inhibitory activity and the chemical structure indicated that the whole structure was required for inhibitory activity of PE-104. PE-104 did not inhibit the caseinolytic activities of pepsin, papain and trypsin at 10 mM, the dose of which inhibited renin activity by more than 80%. In normotensive rats, infusion of PE-104 (20 mg/kg/min) abolished increases in blood pressure, plasma renin activity and plasma angiotensin I concentration after injection of renin. In two kidney model renal hypertensive rats, infusion of PE-104 resulted in decreases in blood pressure, plasma renin activity and plasma angiotensin I concentration.

Angiotensin I↗
PubMed1976

Prompt elevation of rat serum alpha-fetoprotein by acute liver injury following a single injection of ethionine.

The mechanism of increased alpha-fetoprotein (AFP) production following a single injection of ethionine was investigated by using rats aged 5 weeks at the time of killing. Marked elevations of serum AFP concentrations occurred within 4 days in both male and female rats after administration of DL-ethionine or L-ethionine, although the increased levels of serum AFP and liver triglyceride in the adults were less marked in the male than in the female. No apparent necrosis of liver cells was observed in ethionine-treated rats. Frequent administrations of adenosine triphosphate after a single dose of ethionine prevented the increases in liver triglyceride and serum AFP levels. The increased concentrations of serum AFP, reaching a maximum level within 4 days, occurred before a slight increase in incorporation of 3H-thymidine into liver DNA. The serum AFP from ethionine-treated rats was immunologically and electrophoretically indistinguishable from that of fetal, carbontetrachloride-treated or hepatoma-bearing rats. These observations suggest that the increased production of AFP in ethionine-treated rats is closely associated with hepatic injury and is not the consequence of liver cell regeneration.

Adenosine Triphosphate↗
PubMed1976

Renin inhibitory effect of synthetic phosphorylethanolamine (PE-104) in the rat.

1. The renin inhibitory effect of 2-[4-(4'-chlorophenoxy)phenoxy - acetylamino]ethylphosphoryl-ethanolamine (PE-104) was examined both in vitro and in vivo. 2. PE-104 inhibited the rate of angiotensin formation from dog renin and renin substrate reaction. The Ki value was 2 mmol/l and the inhibition was competitive. 3. In normotensive rats, infusion of PE-104 abolished the increases of blood pressure and plasma angiotensin I concentration due to renin injection. In renal hypertensive rats, infusion of PE-104 decreased blood pressure and this was associated with a decrease of plasma angiotensin I concentration. 4. These observations confirm that PE-104 is a renin inhibitor.

Angiotensin II↗
PubMed1976

The primary structure of non-initiator methionine transfer ribonucleic acid from Bakers' yeast. I. Purification and complete digestion with ribonuclease T1 and pancreatic ribonuclease A.

The methionine acceptor activity of a crude tRNA from bakers' yeast was resolved into two peaks (I and II) by column chromatography on DEAE-Sephadex A-25 with a 1 M phosphate system. Methionine tRNA from peak II was not formylated by E. coli methionyl-tRNA transformylase [EC 2.1.2.9.] after being charged with methionine, whereas that from peak I was formylatable under the same conditions. A substantial amount of unlabelled methionine tRNA, tRNAMetm, was highly purified from the peak II fraction by successive chromatographic procedures. The purified tRNAMetm was digested with pancreatic ribonuclease A [EC 3.1.4.22] and ribonuclease T1 [EC 3.1.4.8]. The digestion products were isolated into individual components and completely sequenced. The results of sequence analysis of the two RNase digests were in good agreement and indicated that the chain length of this tRNA is 76, including 13 modified nucleotides. These oligonucleotide fragments can be constructed into a unique total sequence, assuming a few conventional features of clover leaf structure for the tRNA was established by analyses of partial digestion products with RNase T1, as reported in the accompanying paper.

Base Sequence↗
PubMed1976

The primary structure of non-initiator methionine transfer ribonucleic acid from Bakers' yeast. II. Partial digestion with ribonuclease T1 and derivation of the complete sequence.

Large oligonucleotides obtained from partial RNase T1 digestion of tRNAMetm from bakers' yeast (S. cerevisiae, strain Y 185) were isolated by chromatographic procedures and sequenced. The complete sequence of the tRNAMetm was established from the results of this partial digestion, together with those of the complete RNase T1 and A [EC 3.1.4.8 and 22] digestions of tRNAMetm reported in the preceding paper. The structure of this tRNAMetm was arranged into a clover leaf comparable with those of other tRNAMet species including bakers' yeast initiator tRNA.

Base Sequence↗
PubMed1976

Renin inhibition by synthetic phosphatidyl and phosphorylethanolamines.

Renin inhibitory effects of about 30 kinds of newly synthesized Phosphatidyl-E and Phosphoryl-E were studied in vitro and in vivo. Among the synthetic Phosphatidyl-E, PE (SEE ARTICLE) SERies were the most potent and these were stronger than natural Phosphatidyl-E. We also confirmed that the converison from the original Phosphatidyl-E, so called prerenininhibitor, to lyso-form to exhibit renin inhibition as mentioned by Sen et al15,16 and Baggio et al.20 was not essential. But a stronger inhibition to renin was observed in PE-72, one of synthetic Phosphoryl-E analogues. PE-104, Phosphoryl-E without long fatty acid chain, was the most potent inhibitor in this study. PE-72 and PE-104 inhibited the reaction between dog renin and substrate in a competitive way. In dogs and rats, Phosphoryl-E decreased hypertensive responce and increase angiotensin I concentration induced by the exogenous renin. Hypotensive effects of Phosphatidyl-E and Phosphoryl-E were also demonstrated in renal hypertensive rats and not in normotensive rats.

Angiotensinogen↗
PubMed1976

Continuous monitoring of circulating blood hematocrit.

The relationship between the hematocrit value and the absolute value of impedance of whole blood was analyzed. The results indicated that the hematocrit value was linearly proportional to the logarithm of the impedance of whole blood over the range of hematocrit values of 10 to 60% with a correlation coefficient of 0.995. The circuit used for detection of the impedance of whole blood was described. It required no adjustments during measurements and had a wide linear range. The sources of error during continuous measurements were the rate of blood flow through the sensor cell, the temperature of the blood, and the concentrations of plasma proteins and ions. Accordingly, the flow and temperature of blood were kept constant during measurements. Changes in the concentrations of plasma proteins and ions within physiological ranges caused errors of +/- 2.0%. Typical results of continuous measurements were presented, showing that the hematocrit values obtained by this method agreed well with those obtained by the conventional methods from the packed cell volume. An advantage of this method over the conventional methods was that it could follow rapid and transient changes in the hematocrit.

Animals↗