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Biomedical subjects

M Noguchi

Publications and source records attributed to M Noguchi.

At least 757 records · Page 42Linked to original sources
PubMed1982

[Studies on absorption, distribution and excretion of 14C labelled sodium 7 beta-[(2R, 3S)-2-(4-ethyl-2,3-dioxo-1-piperazinecarboxamido)-3-hydroxybutanamido]-7-methoxy-3-[(1-methyl-1H-tetrazol-5-YL)thiomethyl]-3-cephem-4-carboxylate (14C-T-1982) in mice and rats].

Absorption, distribution and excretion of sodium 7 beta-[(2R,3S)-2-(4-ethyl-2,3-dioxo-1-piperazinecarboxamido)-3-hydroxybutanamido ]-7 alpha-methoxy-3-[(1-methyl-1 H-tetrazol-5-yl) thiomethyl]-3-cephem-4-carboxylate (T-1982) were studied in rats and mice using of 14C-T-1982. 1. The binding rate of 14C-T-1982 to serum protein was about 16% in mouse, 27% in rat and 50% in human. 2. After intravenous administration to mice and rats, blood levels of radioactivity diminished rapidly. While, after subcutaneous administration to mice and intramuscular administration to rats, blood levels reached rapidly to high concentration and, declined gradually in comparison with intravenous studies. 3. Radioactivity after parenteral administration to rats and mice was distributed high into kidney, following by liver, stomach, heart, lung and ovarium, but low into brain. In new born rats, tissue levels diminished slower than that of adult rats. 4. With regard to oral administration to mice, almost all radioactivity was found in feces. This result suggested that T-1982 was hardly absorbed from gastrointestinal tracts. Urinary excretion rate after intravenous administration was about 60% in mice and 19% in rats, and the other radioactivity was found in feces. 5. In rats, radioactivity was excreted in bile at biliary excretion rate of about 80% after intravenous administration. 6. After intravenous administration to nursed rats, radioactivity was hardly detected in gastrointestinal tracts of sucklings. And from the study on distribution of radioactivity in pregnant mice, it was suggested that T-1982 scarcely passed placenta. 7. Excretion pattern after multiple administration to rats was similar to that of single administration. This result suggested that T-1982 did not produce accumulation of it in body.

Absorption↗
PubMed1982

Localization of receptors for Dolichos biflorus agglutinin in early post implantation embryos in mice.

The distribution of receptors for Dolichos biflorus agglutinin (DBA) was studied by histochemical staining of paraffin sections with HRP- or FITC-DBA in mouse embryos at stages ranging from 4.5 to 12.5 days post coitum. Preimplantation blastocysts did not express DBA receptors. The receptors first appeared in primitive endoderm cells in 5-day embryos. In 5.5- to 7.5-day embryos, both the parietal and extraembryonic visceral endoderm cells expressed the receptors. Reichert's membrane was negative for DBA receptors. The columnar cells of the embryonic visceral endoderm (EVE) strongly expressed the receptors, while the flat cells at the antimesometrial pole of the EVE were negative or patchily positive. In 8- to 9-day embryos, the receptors were expressed in the epithelium of the fore- and hindgut. In 9.5- to 12.5-day embryos, the epithelial cells of various regions of the gut expressed the receptors, although the endodermal cells of the liver and the pancreas, both derived from the foregut, did not express them. In 8- to 12.5-day embryos both the visceral and parietal yolk sac endoderm were positive in DBA receptors. The receptors were localized exclusively on the free surface facing the yolk cavity or on the luminal surface and subjacent cytoplasm. All endodermal cells which were positive are known to have absorptive activity. All other tissues in these stages were negative in DBA receptors.

Animals↗
PubMed1981

Degradation of mesoheme and hydroxymesoheme catalyzed by the heme oxygenase system: involvement of hydroxyheme in the sequence of heme catabolism.

Mesoheme bound to heme oxygenase protein was easily degraded to mesobiliverdin by incubation with NADPH-cytochrome c reductase and NADPH. The features of mesoheme degradation were very similar to those of protoheme degradation catalyzed by the heme oxygenase system; an intermediate compound having its absorption maximum at 660 nm appeared in the couse of mesoheme degradation and this compound is presumably equivalent to the 688 nm compound which appears in the course of protoheme degradation. Hydroxymesoheme was chemically prepared and a complex of hydroxymesoheme and heme oxygenase was prepared. The complex was fairly stable in air, but when the complex was incubated with the NADPH-cytochrome c reductase system, the hydroxymesoheme bound to heme oxygenase was readily converted to mesobiliverdin through the 660 nm compound as an intermediate. It is evident that hydroxyheme is a real intermediate of heme degradation in the heme oxygenase reaction and that the 688 nm compound (or the 660 nm compound in the mesoheme system) is located between hydroxyheme and the biliverdin-iron chelate. The ferrous state of heme-iron may also be necessary for the onset of further oxidation of hydroxyheme.

Animals↗
PubMed1981

Photo-reversal by monochromatic light of the carbon monoxide-inhibited heme degradation catalyzed by the reconstituted heme oxygenase system.

Photo-reversal of the carbon monoxide inhibition of heme oxygenase reaction by monochromatic light was investigated. Heme degradation in either the microsomal or the reconstituted heme oxygenase system was inhibited by CO. In both systems the extents of Co inhibition were dependent on the CO/O2 ratio and were nearly equal at a given CO/O2 ratio. In the reconstituted heme oxygenase reaction using a highly purified heme oxygenase preparation the relationship between the intensity of light and the degree of reversal of the CO inhibition of heme degradation as expressed in terms of delta K/Kd was not linear, but the tentatively obtained photochemical action spectrum exhibited the peaks of reversal at about 420, 540, 570, and 640 nm and suggested the occurrence of at least two steps of CO inhibition in the overall sequence of heme degradation. One could be ascribed to protoheme and the other was supposed to be the 688 nm compound which is an intermediate locating between hydroxyheme and the biliverdin-iron complex in the sequence of heme degradation.

Animals↗
PubMed1981

Mechanism of the excitatory action of motilin on isolated rabbit intestine.

Synthetic motilin caused a dose-dependent contraction on isolated rabbit intestinal segments, including the duodenum, ileum, and rectum. The contraction of duodenum was significantly greater than that in the ileum or rectum. In the duodenum, motilin was approximately 100 times as potent as acetylcholine on molar basis. The motilin-induced contractions were not influenced by atropine, chlorpheniramine, cimetidine, phentolamine, propranolol, cinanserin, 1-sar-8-ala-angiotensin II, or aspirin. Motilin did not affect the contraction induced by transmural electrical stimulation or acetylcholine. The response to motilin was unaffected by acetylcholine. Removal of Ca++ from bathing media or verapamil suppressed the motilin-induced contractions to a significantly greater extent than the contractions induced by acetylcholine. Thus, it may be concluded that motilin produces intestinal contractions by acting directly on smooth muscles, but not by acting on pharmacologically known drug receptors nor by releasing neurotransmitters such as endogenous acetylcholine. Motilin does not appear to modify autonomic nerve functions.

Acetylcholine↗