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31.
Souichi Satoh †Tatsuo Kimura †Masahiro Toda †Mutuko Maekawa †Satoshi Ono †Hirokazu Narita Hiroyuki Miyazaki Toshihiko Murayama Yasuyuki Nomura 《Journal of neurochemistry》1997,69(5):2197-2205
Abstract: Nitrogen oxides, such as nitric oxide, have been shown to regulate neuronal functions, including neurotransmitter release. We investigated the effect of S-nitroso-l -cysteine (SNC) on noradrenaline (NA) release in the rat hippocampus in vivo and in vitro. SNC stimulated [3H]NA release from prelabeled hippocampal slices in a dose-dependent manner. SNC stimulated endogenous NA release within 30 min to almost five times the basal level in vivo (microdialysis in freely moving rats). In a Na+-containing Tyrode's buffer, SNC-stimulated [3H]NA release was inhibited 30% by the coaddition of l -leucine. In the Na+-free, choline-containing buffer, SNC-stimulated [3H]NA release, which was similar to that in the Na+-containing buffer, was inhibited markedly by l -leucine, l -alanine, l -methionine, l -phenylalanine, and l -tyrosine. The effects of the other amino acids examined were smaller or very limited. The effect of l -leucine was stronger than that of d -leucine. A specific inhibitor of the L-type amino acid transporter, 2-aminobicyclo[2.2.1]-heptane-2-carboxylate (BCH), inhibited the effects of SNC on [3H]NA release in the Na+-free buffer. Uptake of l -[3H]leucine into the slices in the Na+-free buffer was inhibited by SNC, BCH, and l -phenylalanine, but not by l -lysine. The effect of SNC on cyclic GMP accumulation was not inhibited by l -leucine, although SNC stimulated cyclic GMP accumulation at concentrations up to 25 µM, much less than the concentration that stimulates NA release. These findings suggest that SNC is incorporated into rat hippocampus via the L-type-like amino acid transporter, at least in Na+-free conditions, and that SNC stimulates NA release in vivo and in vitro in a cyclic GMP-independent manner. 相似文献
32.
33.
Hiromi Takahashi-Iwanaga Toshihiko Iwanaga Yuzuru Sakamoto Tsuneo Fujita 《Cell and tissue research》1995,280(3):491-497
In previous ultrastructural studies we have shown that at the tip of intestinal villi in guinea pigs, effete enterocytes are separated into two portions: a thin apical cytoplasm to be exfoliated into the lumen and a major basal portion to be ingested by lamina propria macrophages. During this process, intraepithelially disposed, large granular lymphocytes interdigitate with enterocytes in a complex manner. In the present study, the relation between the enterocytes and the lymphocytes in the villous epithelium of the guinea pig small intestine is described by use of transmission and scanning electron microscopy in an attempt to visualize the roles and activities of the lymphocytes more clearly. The lymphocytes project numerous pointed processes into effete enterocytes, even piercing them. Enterocytes are deeply indented or perforated, probably as a result of the encroaching lymphocyte processes. Some enterocytes are separated into apical and basal portions by numerous large excavations in the cytoplasm. These findings indicate that repeated perforating penetration of the lymphocytes induces cell cleavage. Supporting this supposition, our microcinematographic observations demonstrate the alternate protrusion and withdrawal of processes of lymphocytes. The processes advance with a pointed end, and subsequently, retract with a rounded end in a cycle of 8–18 seconds. 相似文献
34.
35.
A photomicrobial sensor consisting of immobilized Chlorella vulgaris and an oxygen electrode has been developed for selective determination of phosphate. When 40 mM phosphate was added to the sensor system, the photocurrent increased to a maximum under light irradiation with a response time of 1 min. The current increased with increasing phosphate concentration in the range 8–70 mM. Selectivity of the sensor was satisfactory. Good agreement was obtained between the phosphate concentrations in lake water determined by the photomicrobial sensor and by conventional colorimetry (correlation coefficient 0.96). 相似文献
36.
Genetic structure of the IncN plasmid N3 总被引:4,自引:0,他引:4
N3, a plasmid of incompatibility group N (IncN) was mapped by cleavage with restriction endonucleases. The restriction fragments were cloned into vector plasmids. All of the genes unique to IncN plasmids such as specific replication machinery, a restriction-modification system, and repair functions were located on a large portion which had no cleavage sites for many of the site-specific six base-identifying restriction endonucleases tested. 相似文献
37.
George G. Rose M.D. Toshihiko Yajima 《In vitro cellular & developmental biology. Plant》1977,13(11):749-768
Summary Fetal mouse lungs were cultivated, using the dual-rotary circumfusion system for tissue culture, and their histotypic development
was surveyed for 75 days by phase-contrast and electron microscopy. Alveoli, terminal bronchioles and alveolar macrophages
were photographed periodically with still and time-lapse phase-contrast microscopy. Their histotypic appearance was confirmed
by electron micrographs of the 1- and 2 1/2-month-old specimens. These revealed typical alveoli surrounded by a basal lamina
and composed of types I and II pneumocytes containing various lamellar-body forms within the type II cells, the alveolar lumen,
and the alveolar macrophages. There was a shift from almost all type II cells in the 1-month-old alveoli to the presence of
frequent type I cells as constituents of the alveoli in the 2 1/2-month-old cultures. The terminal bronchioles were tubules
consisting of ciliated cells with Clara cells interspersed between them. The ciliated cells contained as many as 30 cilia
or basal bodies per section and numerous microvilli. They were attached to each other and to the Clara cells by junctional
complexes and accessory desmosomes which were generally in the apical ends of the cells. The Clara cells typically had glycogen
granules interspersed between lamellae of the endoplasmic reticulum, contained numerous well dispersed mitochondria, occasional
lysosome-like granules and crystalloid bodies which appeared to be tubular. Some Clara cells presented a moderately dense
secretory granule in the center of the whorl of the endoplasmic reticulum.
This work supported by Grant HL19684 from the National Heart and Lung Institute, National Institutes of Health.
Pregnant Strong A mice were kindly supplied by Dr. Henry Browning of the Department of Anatomy. 相似文献
38.
Toshihiko Ubuka Masahiro Kinuta Reiko Akagi Shozo Kiguchi Miyabi Azumi 《Analytical biochemistry》1982,126(2):273-277
A procedure for the simultaneous preparation of S-sulfo-l-cysteine and l-alanine 3-sulfinic acid is described. The method is based on the quantitative reaction between sulfite and S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. The yield was 95% for S-sulfo-l-cysteine and 91% for l-alanine 3-sulfinic acid. The reaction was also applied to the quantitative determination of sulfite in biological materials. In this procedure, sulfite reacts with S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. Separation of the reaction product, S-sulfo-l-cysteine, is done by ion-exchange fractionation, and it is determined with acid ninhydrin reagent 2 (M. K. Gaitonde, 1967, Biochem. J.104, 627–663). The recovery was 96.8 ± 0.3%. 相似文献
39.
Summary Deficiency of inorganic phosphate caused the hyper production of invertase and the derepression of acid phosphatase in a continuous culture ofSaccharomyces carlsbergensis. The specific invertase activity was 40,000 enzyme units per g dry cell weight at a dilution rate lower than 0.05 h–1 with a synthetic glucose medium of which the molecular ratio of KH2PO4 to glucose was less than 0.006. This activity is eight fold higher than in a batch growth and 1.5 fold as much as the highest enzyme activity observed so far in a glucose-limited continuous culture.For the hyper production of invertase, it is necessary to culture the yeast continuously by keeping the Nyholm's conservative inorganic phosphate concentration at less than 0.2 m mole per g dry weight cell. The derepression of acid phosphatase brought about by phosphate deficiency, was similar in both batch and continuous cultures.Nomenclature D
dilution rate of continuous culture (h–1)
- Ei
invertase concentration in culture (enzyme unit l–1)
- Ep
acid phosphatase concentration in culture (enzyme unit l–1)
- P
inorganic phosphate concentration in culture (mM)
- S
glucose concentration in culture (mM)
- X
cell concentration in culture (g dry weight cell l–1)
Greek Letter
specific rate of growth (h–1)
Suffix f
feed
- 0
initial value 相似文献
40.
Cellular localization of thiol-proteinase inhibitor in the epidermis of the newborn rat 总被引:4,自引:0,他引:4
Dr. Kimie Fukuyama Osamu Ohtani Toshihiko Hibino William L. Epstein 《Cell and tissue research》1982,222(2):313-323
Summary In cichlid, poecilid and centrarchid fishes luteinizing hormone releasing hormone (LHRH)-immunoreactive neurons are found in a cell group (nucleus olfactoretinalis) located at the transition between the ventral telencephalon and olfactory bulb. Processes of these neurons project to the contralateral retina, traveling along the border between the internal plexiform and internal nuclear layer, and probably terminating on amacrine or bipolar cells. Horseradish peroxidase (HRP) injected into the eye or optic nerve is transported retrogradely in the optic nerve to the contralateral nucleus olfactoretinalis where neuronal perikarya are labeled. Labeled processes leave this nucleus in a rostral direction and terminate in the olfactory bulb. The nucleus olfactoretinalis is present only in fishes, such as cichlids, poecilids and centrarchids, in which the olfactory bulbs border directly the telencephalic hemispheres. In cyprinid, silurid and notopterid fishes, in which the olfactory bulbs lie beneath the olfactory epithelium and are connected to the telencephalon via olfactory stalks, the nucleus olfactoretinalis or a comparable arrangement of LHRH-immunoreactive neurons is lacking. After retrograde transport of HRP in the optic nerve of these fishes no labeling of neurons in the telencephalon occurred. It is proposed that the nucleus olfactoretinalis anatomically and functionally interconnects and integrates parts of the olfactory and optic systems. 相似文献