The Tohoku Journal of Experimental Medicine
Online ISSN : 1349-3329
Print ISSN : 0040-8727
ISSN-L : 0040-8727
Volume 103, Issue 4
Displaying 1-6 of 6 articles from this issue
  • AKIRA RIKIMARU
    1971 Volume 103 Issue 4 Pages 317-329
    Published: 1971
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    The contractile properties of the smooth muscle of guinea-pig taenia coli in organ culture were investigated in relation to the histochemical observation on its innervation. The smooth muscle preparations were cultured in the medium rich in horse serum and chick embryo extract. They preserved responsiveness to nicotine and transmural stimulation at low frequencies for more than three weeks. On the other hand, those cultured in the medium contained only lower concentration of horse serum and deficient in chick embryo extract lost such responsiveness after two to three weeks of incubation. It is evident from these data that the latter condition of culture would be adequate for the experiment in which the smooth muscle is maintained but the nerve element have to be eliminated. In this condition, the preparations on the 4th day of culture failed to produce a relaxation by transmural stimulation at high frequencies, though it was produced at low frequencies and by nicotine. The fluorescence of catecholamines disappeared at the same stage of culture, but no supersensitivity to noradrenaline and acetylcholine was observed. Histofluorometric observation of the taenia before culture revealed the presence of intensely fluorescent nerve fibers scattered in the muscular layers and around the nonfluorescent ganglion cells in Auerbach's plexus. Neither fluorescent ganglion cells nor characteristic fluorescence of 5-HT could be observed in Auerbach's plexus. These results strongly confirmed the presence of non-adrenergic inhibitory neurons within the taenia. Histofluorometric data ruled out the possibilities of participation of dopamine and 5-HT in this inhibitory mechanism. The transmitter of the intramural inhibitory neurons did not show any fluorescence by the treatment with formaldehyde vapor.
    Download PDF (1949K)
  • TORU MIYAJI
    1971 Volume 103 Issue 4 Pages 331-369
    Published: 1971
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    As a model experiment on the study of toxicity of a compound, acute, short-term and long-term toxicity tests on Furylfuramide (2-(2-Furyl)-3-(5-nitro-2-8- furyl) acryl amide) were performed using Nitrofurazone (5-nitro-2-furaldehyde semicarbazone) and sorbic acid as control compounds. As the most conspicuous changes, hypertrophy of liver cells with clear cytoplasm was noted within a week of feeding. These cells were first located around the central vein and increased in number with time toward the peripheral portion of the lobule. In spite of the long-term experiments up to two years in rats and mice, no progressive lesion of the liver followed by the hypertrophy. No cumulative effect of Furylfuramide was noted in any organ. The hypertrophy of liver cells was reversible, when animals were switched to basal diet and kept on it for a certain length of time. A concentration of 0.125% in the diet was considered to be the tolerable safe dose of Furylfuramide. High incidence of spontaneous tumors developed in mice fed on Furylfuramide and control diet for two years was described. There was no difference in incidences between groups.
    Download PDF (6501K)
  • TORU MIYAJI
    1971 Volume 103 Issue 4 Pages 371-379
    Published: 1971
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    Download PDF (1969K)
  • TORU MIYAJI
    1971 Volume 103 Issue 4 Pages 381-388
    Published: 1971
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    As food additives are prone to be taken every day, it was considered important to test their effect on reproduction and their possible teratogenecity. Mice and rats were fed 0.0125% Furylfuramide diet continuously for four generations, and per cent of conception, birth rate, number of litter per female, rate of weaning and body weight at the time of weaning were examined. There was no difference between animals fed Furylfuramide and control diet.
    Teratogenicity of Furylfuramide was studied on mice and compared with that of Nitrofurazone and control diet. Furylfuramide did not have any teratogenic effect on fetuses and no malformation was noted among fetuses obtained by Cesarean section. Fertility of male mice was not impaired by Furylfuramide feeding in contrast to Nitrofurazone, which reduced fertility of males. The fetuses were smaller in size compared with the Furylfuramide group and controls.
    Download PDF (1078K)
  • YUTAKA HORI, TAKUKO YANASE, YUTAKA HATTORI, CHIKAYOSHI TERADA, SHOZABU ...
    1971 Volume 103 Issue 4 Pages 389-405
    Published: 1971
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    The cerebral mechanism in the training process of manual work was examined by simultaneous recordings of motion analysis, EMG and EEG of the subjects in the course of acquiring skill in chain-stitching. Four phases of progress were distinguished: 1) the period of increasing speed, 2) agitation period of unrhythmic and inaccurate movement. 3) the period of recovering work accuracy, and 4) the period of established motion regularity. In the discharges of neuro-muscular unit of working muscles, the regularity appeared with the advance of training, and this proved that corticalization changed to spinalization in the central neuro-mechanism. In EEG θ waves of the trained appeared localizing in the left frontal region during work. Previous suggestions on procedure reduced agitation period in the course of training. From these results, it seemed likely that simple repetitive manual work like stitching was sustained by a kind of conditioned reflex and by subcortical reflex mechanism.
    Download PDF (833K)
  • HIROAKI OKABE, TADASHI SHIMOJO
    1971 Volume 103 Issue 4 Pages 407-418
    Published: 1971
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    The incorporation rates of radioactivity into both lipid and acid soluble fractions of mouse tissues such as liver, kidney and small intestine and others were followed up at various time intervals (5min -24hr) after the intraperitoneal administration of ethanolamine-2-14C. The percentages of radioactivity of individual phospholipids were also determined in three tissues. The quantitative isolation of individual radioactive compounds from acid soluble fractions was performed using various chromatographic techniques.
    The pool sizes and the specific activities of ethanolamine and its metabolites such as phosphoryl-ethanolamine, glycerylphosphoryl-ethanolamine, phosphatidylethanolamine, lysophosphatidyl-ethanolamine and phosphatidyl-choline were determined at various time intervals. From their values the turnover rates of various reactions in phosphatidyl-ethanolamine metabolism in mouse liver, kidney and small intestine were estimated by means of Zilversmit's equation.
    Download PDF (609K)
feedback
Top