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The bronchodilator effect of salbutamol formulated in hydrofluoroalkane-134a (HFA-134a), a chlorofluorocarbon (CFC)-free propellant for metered dose inhalation (MDI) devices, was compared with that of salbutamol formulated in CFC in anesthetized dogs.Bronchospasms were induced by the intravenous injection of histamine, and bronchial resistance was measured by the method of Konzett and Rossler.While the placebo vehicles (HFA-134a and CFC propellants) had no significant effect on histamine-induced bronchospasms, the salbutamol/HFA-134a and salbutamol/CFC MDI formulations had equivalent dose-related inhibitory effects.These data indicated that salbutamol formulated in HFA-134a and that in CFC propellant are bioequivalent.

In order to examine the penetration of N-[4-[4-(diphenylmethyl)-1-piperazinyl]-butyl]-3-(6-methyl-3-pyrid yl) acrylamide (AL-3264, CAS 118420-47-6), a new antiallergic agent, into the brain, the antihistamine activities in the central and peripheral tissues from the rats and monkeys orally treated with AL-3264 were measured in comparison with those of ketotifen, oxatomide, mequitazine and terfenadine. These 5 drugs dose-relatedly suppressed the histamine-induced dye leakage in the rat skin and, except terfenadine, inhibited the binding of 3H-mepyramine to brain homogenates obtained from the rats treated orally with the drugs. The ratio (0.07) of AL-3264 for the central (3H-mepyramine binding) to peripheral (dye leakage) antihistamine activities was lower than that of ketotifen, oxatomide and mequitazine, and higher than that of terfenadine. The serum and cerebrospinal fluid (CSF) samples, which were collected from the monkeys treated with 80 mg/kg p.o. of AL-3264, terfenadine or oxatomide, inhibited the histamine-induced contractions in isolated guinea pig trachea. The ratio (0.003) of AL-3264 for the central (CSF) to peripheral (serum) antihistamine activities was lower than that of terfenadine and oxatomide. These results suggest that AL-3264 is poorly accessible to the brain, and may be regarded as a non-sedative antiallergic agent.

Antiallergic effects of AL-3264 (N-[4-[4-(diphenylmethyl)-1-piperazinyl]butyl]-3-(6-methyl-3- pyridyl)acrylamide, CAS 118420-47-6) were compared with those of ketotifen, oxatomide, azelastine and tranilast in experimental animals. AL-3264 inhibited passive cutaneous anaphylaxis (PCA) in rats with an ED50 value of 6.1 mg/kg p.o. In inhibiting PCA, AL-3264 was the most potent among the antiallergic drugs examined. The anti-PCA effect of AL-3264 was long-lasting. Tolerance was not produced by repeated administration of AL-3264. AL-3264 inhibited antigen-induced bronchoconstriction in actively sensitized rats and in passively sensitized guinea pigs, with ED50 values of 14.5 and 0.44 mg/kg p.o., respectively. In the in vitro experiments, AL-3264 inhibited 5-lipoxygenase activity of guinea pig leukocytes with an IC50 value of 4.9 mumol/l, being the most potent among antiallergic drugs examined, and suppressed the antigen-induced histamine release from rat peritoneal mast cells with an IC50 value of 12.2 mumol/l. AL-3264 antagonized histamine-induced contractions in isolated guinea pig trachea with an IC50 value of 0.16 mumol/l. These results suggest that AL-3264 is an orally active, potent and long-lasting antiallergic compound which inhibits 5-lipoxygenase activity, histamine release and histamine H1 receptors at the similar concentrations.

Experimental liver injury was produced in mice by the immunological technique. The utility of these models as an immunopharmacological method was investigated. The first model was produced by the injection of anti-basic liver protein (BLP) rabbit antibody into DBA/2 mice that had been previously immunized with rabbit IgG. The second liver injury was caused by injection of anti-liver specific protein (LSP) rabbit antibody into DBA/2 mice. The third model was produced by the injection of bacterial lipopolysaccharide (LPS) into Corynebacterium parvum pretreated ddY mice. In all injury models, extensive liver parenchymal cell damage was estimated by elevation of glutamate transaminase (GOT and GPT) activity. These were confirmed by histopathological studies of the liver. Typical histopathological changes in the liver from injured mice were submassive hepatocellular necrosis and infiltration of granulocytes and lymphocytes into the portal tract and sinusoid in the necrotic lesion. Administration of prednisolone and cyclophosphamide for 10 days prior to injection of eliciting antibodies or LPS suppressed the elevation of serum transaminase levels in all experimental liver injury models. Cianidanol and sylibin inhibited the elevation of GOT and GPT in anti-BLP induced liver injured mice. These evidences suggest that the above models are suitable for investigating the remedy for liver diseases.

The effects of OKY-046, a selective thromboxane A2 (TXA2) synthetase inhibitor, and ONO-3708, a novel TXA2 receptor antagonist, on liver disease were investigated in mice. The liver injury was induced by either an injection of antibasic liver protein (BLP) antibody into DBA/2 mice that had been previously immunized with rabbit IgG or by an injection of bacterial lipopolysaccharide (LPS) into Corynebacterium parvum (C. parvum) pretreated DDY mice. 1) In both injury models, clear elevation of glutamate transaminase (GOT and GPT) activity due to extensive liver parenchymal cell damage was observed; this was confirmed by significant histopathological changes in the liver. 2) Typical histopathological changes in the liver were submassive hepatocellular necrosis in the anti-BLP antibody-induced injury model and focal necrosis in the LPS-induced model. Inflammation and increased cell infiltration in portal connective tissue were observed in both cases. 3) Administration of OKY-046 (50 mg/kg) and ONO-3708 (0.5, 1.0 and 2.0 mg/kg) suppressed the elevation of serum GOT and GPT levels and histopathological changes in both experimental liver injury models. 4) Indomethacin inhibited the development of liver disease caused by anti-BLP antibody but not by bacterial LPS. Prostaglandin I2 inhibited the elevation of serum GOT and GPT levels and histopathological changes of the liver in the mice treated with anti-BLP antibody and showed the tendency to inhibit the development of liver injury caused by bacterial LPS.