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H Fukuda

Publications and source records attributed to H Fukuda.

At least 1,189 records · Page 66Linked to original sources

[Effects of benzodiazepine derivatives on gamma-motor system in rats (author's transl)].

Effects of four benzodiazepine derivatives on gamma-activity were examined in the anesthetized rat. Diazepam and 5-(o-chlorophenyl)-1-methyl-7-nitro-1, 3-dihydro-2H-1, 4-benzodiazepin-2-one(ID-690) in a dose of 2.5 mg/kg (i.p.) showed depressant effects on gamma-activity. The depressant effects of 5.0 mg/kg (i.p.) lasted for more than 60 min. Nitrazepam had a slightly weaker effect than the above two drugs and the effect was evident after an administration of 5.0 mg/kg; the effect of 10 mg/kg(i.p.) lasted for more than 90 min. The effect of clonazepam was much weaker than effects of the other three drugs. A dose of 20 mg/kg(i.p.) was required to produce an obvious depressant action, and the effect appeared after a longer latency of about 20 min. ID 690 (5.0 mg/kg, i.p.) depressed the augmented response of the gamma-activity in response to pinna stimulation. The effect of diazepam on the augmented responses was observed with the same dose. In contrast, much higher doses of nitrazepam and clonazepam were required to induce an obvious depressant effect on the augmented gamma-activity. It is suggested that the difference in potency in depressing gamma-activity of these derivatives is one of the factors characterizing their pharmacological properties.

Animals↗

Purification and properties of glyoxylate reductase I from baker's yeast.

The purification and properties of NADPH-linked glyoxylate reductase [EC 1. 1. 1. 79] from baker's yeast were studied. Two active fractions (peak I and peak II) were isolated by DEAE-cellulose column chromatography. The peak I fraction was purified to homogeneity by the criteria of disc gel electrophoresis and tentatively designated glyoxylate reductase I. Its molecular weight was calculated to be 31,000 from gel filtration measurements. The enzyme reduced glyoxylate 7 times faster than hydroxypyruvate and was specific for NADPH. The enzyme showed optimum activity between pH 5.5 and 7.2. The Michaelis constants for glyoxylate and NADPH were found to be 13 mM and 4 microM, respectively. The enzymic activity was not significantly affected by anions, except for nitrate and iodide, which were inhibitory.

Alcohol Oxidoreductases↗

[Suprasternal bone (author's transl)].

Human skeletons have many variations which may occasionally necessitate distinction from pathologic changes. Suprasternal bone is an unfamiliar normal variation in the vicinity of the sternoclavicular joint. It was first described by Béclard in 1820 and thereafter many reports have appeared, mostly in anatomy and embryology. An incidence less than 5% is reported abroad. This report describes the incidence of suprasternal bone in Japanese and a few clinical reference cases. Suprasternal bone is now considered to have derived from the persistent rudiment of epicoracoid which should have normally consisted of the part of manubrium sterni. Suprasternal tubercle is considered to be the osseously fused type of suprasternal bone. The material consisted of two groups: 1) Seventy-four sterna were examined roentgenographically which were removed en bloc from the cadavera. 2) 562 sterna of living subjects were examined roentgenographically by Kattan's method. In the seventy-four cadavera, eight cases had suprasternal bones (10.8%) and fourteen cases had suprasternal tubercles. Among them, three had suprasternal bone and tubercle on each side. In the 562 living subjects, thirty-nine cases had suprasternal bones (6.9%) and eight cases had suprasternal tubercles. Among them, three had both on each side. The incidence of suprasternal bone in Japanese is therefore higher than foreigners' reported previously. Kattan's method employed in this study is simple and excellent to show manubrium sterni and sternoclavicular joint clearly. It is emphasized that suprasternal bone is not uncommon and differential diagnosis from pathologic changes is easy as long as it is kept in mind.

Adult↗

[Effects of diazepam and baclofen on the anemic decerebrate rigidity in rats (author's transl)].

Effects of diazepam and baclofen on the anemic decerebrate rigidity in rats were studied by using the drugs that modify GABAergic mechanisms of deplete catecholamine. Rigid forelimb tension in anemic decerebrate rats took the form of tonically sustained tension (tonic component), while the phasic tension (phasic component) was induced by mechanical stimulation of hindlimbs. Diazepam exerted a marked dose-dependent inhibition of the phasic component, whereas baclofen produced a similar effect on both tonic and phasic components. In rats pretreated with semicarbazide, the inhibitory effect of diazepam on phasic component was reduced, and the effect of semicarbazide was antagonized by pyridoxine. The effect of diazepam was slightly enhanced by pretreatment with aminooxyacetic acid, and antagonized by picrotoxin. In contrast to diazepam, the depressant actions of baclofen on both components were not affected by semicarbazide, aminooxyacetic acid or picrotoxin. Catecholamine depletion produced by alpha-methyltyrosine or disulfiram significantly reduced the effect of baclofen on the phasic component. It thus appears that GABA is involved in the effect of diazepam on the phasic component, and noradrenaline is involved in the same effect of baclofen in anemic decerebrate rats.

Aminooxyacetic Acid↗

Postnatal development of pituitary-thyroid function in male and female rats: comparison of plasma and thyroid T3 and T4 concentration.

Plasma T4, T3, and TSH, and total and 131l-labeled T4 and T3 in thyroid digests were determined in male and female rats from birth to 30--45 days postnatally. Mothers and offspring were fed a high-iodine Purina diet throughout. In both sexes, plasma T4 was less than 1 microgram/100ml at birth but rose linearly to a peak of 6--7 micrograms/100 ml at day 15. Plasma T3 remained low at 30--40 ng/100 ml until day 10, then rose steeply to 80--100 ng/100 ml at day 20--30. Plasma TSH had a bimodal distribution with an early peak in the intial 1--2 weeks of life and a second rise after day 30. Adult pattern sex differences in plasma TSH appeared by day 30. Labeled T3 was undetectable in thyroid digests until after day 7. Both labeled and stable T3 and T4 concentration and T3/T4 ratios rose progressively during the first 2 weeks of life. After day 7, stable and labeled intrathyroidal T3/T4 ratios were significantly correlated, but the latter was always higher than the former for any given age.

Animals↗