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K Osuga

Publications and source records attributed to K Osuga.

36 records · Page 2Linked to original sources

Antiulcer activity of clotiazepam in rats.

Effect of the anti-anxiety drug clotiazepam on the experimental gastric ulceration induced by restraint and water-immersion stress or aspirin was studied in rats. Clotiazepam prevented the development of each gastric ulcer. From the effect of clotiazepam on aspirin-induced ulceration, we presumed that clotiazepam should have some other antiulcer mechanism in addition to its action on the central nervous system. There was an appreciable correlation between the decrease in the hexosamine level of gastric tissue and associated ulceration. After treatment with aspirin, the hexosamine level was abruptly reduced and was maintained at a low level for several hours. In the clotiazepam -pretreated group, the hexosamine level reduced by aspirin was progressively restored to the intact level. By histological examination with periodic acid-Schiff (PAS)/alcian-blue (AB) staining, clotiazepam increased the amount of gastric mucopolysaccharides decreased by aspirin. Clotiazepam did not affect gastric secretion in pylorus-ligated rats. Atropine and cimetidine inhibited ulceration induced by stress or aspirin and gastric secretion, but did not affect the hexosamine level reduced by aspirin. These results indicate that the antiulcer efficacy of clotiazepam may be attributed to its action not only on the central nervous system, but also on the mucus in gastric mucosa.

Animals↗

[General pharmacology of traxanox sodium. I. Effects on the central, somatic, and autonomic nervous systems, digestive system, urologic organs, and reproductive system].

Traxanox at the upper dose of 300 mg/kg, p.o., showed no effect on the somatic and autonomic nervous systems in the various tests. This agent caused some relaxation of the guinea pig tracheal strip in the resting tone at a concentration of 10(-6)M or more; however, its activity was less potent than that of isoproterenol and paraverine. Traxanox had no competitive antagonistic action against chemical mediators. Treatment of rats with this agent (3 mg/kg, i.v., or 10 mg/kg, s.c.) resulted in an inhibition of gastric (acid) secretion. Intravenous injections of traxanox (1-10 mg/kg) in dogs caused an immediate but transient inhibition of gastric and jejunal movement, and after a short time, slight potentiation of the latter; however, pretreatment with atropine prevented this latter potentiation. In the in vitro test, 10(-4)M traxanox caused contraction of the guinea pig ileum, a response which was inhibited by atropine. Traxanox (300 mg/kg, p.o.), however, did not show any effects on gastrointestinal propulsion in mice, nor did it have any effect on the gastrointestinal mucosa, gastric ulcers or bile secretion in rats. Traxanox (300 mg/kg, p.o.) showed a diuretic action in both normal and adrenoectomized rats. This action, however, was not observed in the rats treated with indomethacin (1 mg/kg, i.p.). This agent (10 mg/kg, i.v.) suppressed the spontaneous uterine contractions of pregnant rats in some cases. These findings suggest that traxanox at doses (1-5 mg/kg, p. o.) showing antiallergic activity has little effect on the central, somatic and autonomic nervous systems, digestive system, urinary organs and reproductive organs.

Animals↗

Experimental hyper-beta-lipoproteinemia and its amelioration by a novel hypolipidemic agent.

Experimental models for hyper-beta-lipoproteinemia were established in rats and the effects of certain hypolipidemic drugs were studied with these models. In the hyperlipemia induced in rats by feeding a high cholesterol diet, Y-9738 [ethyl 2(4-chlorophenyl)-5-ethoxy-4-oxazoleacetate] produced a dose-dependent reduction of serum cholesterol: such hypolipidemic activity was estimated to be about 7 times as great as that of clofibrate. On the other hand, clofibrate induced hepatomegaly at 100 mg/kg, whereas Y-9738 did not at this dosage, which is about 10 times the effective dose. Hyperlipemia induced by high cholesterol and thiouracil was characterized by increased beta-lipoprotein (heparin-calcium and disc electrophoresis). In this model, Y-9738 showed a dose-dependent lowering effect on beta-lipoprotein cholesterol with a marked decrease in the beta/alpha lipoprotein ratio. A tendency was noted for alpha-lipoprotein to be increased. In contrast, clofibrate exerted no effect on this hyper-beta-lipoproteinemia. These results suggest that the above models may be of value in exploring hyper-beta-lipoproteinemia and that Y-9738 may be more useful than clofibrate in the therapy of hyperlipemia.

Animals↗

Inhibition of hypersensitivity reactions by soluble derivatives of baicalein.

Baicalein, a flavonoid, is anti-allergic but only slightly soluble in water. The soluble derivatives of baicalein, disodium baicalein-6-phosphate (BPS) and sodium baicalein-6-sulfate (BSS), were synthesized and examined regarding their effects on hypersensitivity reactions. These derivatives inhibited type I and II reactions as classified by Coombs and Gell. The Arthus reaction belonging to type III reaction, however, was hardly affected with either BPS or BSS. The experimental asthma caused by passive systemic anaphylaxis in guinea pigs was prevented with application of BPS. Thus even by the oral route, BPS appears to be clinically applicable to extensive allergy related diseases.

Aminophylline↗