» Articles » PMID: 2596372

The Inhibition of 5-lipoxygenase by RG 6866

Overview
Journal Agents Actions
Specialty Pharmacology
Date 1989 Nov 1
PMID 2596372
Authors
Affiliations
Soon will be listed here.
Abstract

The generation of leukotrienes C4, D4 and E4 from arachidonic acid is dependent upon the activity of 5-lipoxygenase (5-LOX). The effects of RG 6866 (N-methyl-4-benzyloxyphenylacetohydroxamic acid) on the activity of guinea pig 5-LOX in vitro and in vivo were determined in the present study. The generation of 5-hydroxy-6,8,11,14-eicosatetraenoic acid (5-HETE) from arachidonic acid by isolated guinea pig peritoneal polymorphonuclear (PMN) cells was inhibited by incubation with RG 6866 (IC50 = 0.20 microM). A similar effect (IC50 = 0.23 microM) was observed when 5-HETE production was measured in a supernatant fraction from PMNs. Additionally, the compound did not inhibit 3H-LTD4 binding to guinea pig membranes. In actively sensitized guinea pigs pretreated with indomethacin, propranolol and pyrilamine, RG 6866 inhibited antigen-induced systemic anaphylaxis and LTD4-dependent bronchoconstriction in a dose-dependent manner following oral administration. In the pulmonary anaphylaxis model, significant (p less than 0.05) inhibition of the mortality was observed within 30 min and maintained through four hours after treatment with RG 6866 (50 mg/kg i.g.). Finally, orally administered RG 6866 inhibited the formation of LTC4 in these animals with an ED50 = 24.0 mg/kg. These findings indicate that RG 6866 is an inhibitor of 5-LOX both in vitro and in vivo.

References
1.
Hand J, Schwalm S, Lewis A . Antagonism of antigen-induced contraction of isolated guinea-pig trachea by 5-lipoxygenase inhibitors. Int Arch Allergy Appl Immunol. 1986; 79(1):8-13. DOI: 10.1159/000233934. View

2.
Salonen R . Actions of bronchodilator drugs, glucocorticoid, and their combinations on airways in rats and guinea pigs. Acta Pharmacol Toxicol (Copenh). 1985; 57 Suppl 3:1-38. View

3.
Weichman B, Muccitelli R, OSBORN R, HOLDEN D, Gleason J, Wasserman M . In vitro and in vivo mechanisms of leukotriene-mediated bronchoconstriction in the guinea pig. J Pharmacol Exp Ther. 1982; 222(1):202-8. View

4.
Hanna C, Bach M, Pare P, Schellenberg R . Slow-reacting substances (leukotrienes) contract human airway and pulmonary vascular smooth muscle in vitro. Nature. 1981; 290(5804):343-4. DOI: 10.1038/290343a0. View

5.
Andersson P, BERGSTRAND H . Antigen-induced bronchial anaphylaxis in actively sensitized guinea-pigs: effect of long-term treatment with sodium cromoglycate and aminophylline. Br J Pharmacol. 1981; 74(3):601-9. PMC: 2071757. DOI: 10.1111/j.1476-5381.1981.tb10470.x. View