Inhibitory Effect Of Tranilast Research Articles

Inhibitory Effect of Tranilast on Substance P-Induced Plasma Extravasation in Rat Skin

The effect of tranilast, an inhibitor for IgE-mediated mediator release from mast cells, on plasma extravasation induced by the intradermal injection of substance P in rats was examined. Tranilast (100 mg/kg, intraperitoneally) decreased plasma extravasation induced by substance P (10(-7)-10(-5) M). Tranilast decreased plasma extravasation induced by the amino-terminal peptide substance P1-9 (10(-6)-10(-4) M), which is active for rat mast cells, but not by the carboxy-terminal peptide substance P6-11 (10(-6)-10(-4) M), which is inactive for the mast cells. Therefore, tranilast prevents substance P-induced plasma extravasation most likely by inhibiting mast cell degranulation.

O-220 - Inhibitory effect of Tranilast on free triiodothyronine release by mouse thyroid lobes

O-220 - Inhibitory effect of Tranilast on free triiodothyronine release by mouse thyroid lobes

The effect of tranilast of the generation of reactive oxygen species.

The relative in vitro antioxidant efficacy of tranilast, a new orally active anti-allergic agent, was examined by studying its effects on the generation of reactive oxygen species (ROS) using zymosan-stimulated polymorphonuclear leukocytes and the cell-free, xanthine-xanthine oxidase system. The species investigated were superoxide radical anion (O2-), hydrogen peroxide (H2O2) and hydroxyl radical (OH.). At concentrations comparable to therapeutic blood levels, tranilast reduced both H2O2 and OH. levels. The inhibitory effect of tranilast was dose-dependent and all ROS levels examined were significantly decreased at the concentration of 100 micrograms/ml. This antioxidant effect of tranilast appeared to stem from its capability to scavenge ROS because the suppression of ROS was observed in both ROS generation systems at higher concentrations, even though the possibility existed that tranilast directly inhibited nicotineamide adenine dinucleotide phosphate oxidase and/or xanthine oxidase activity. This unique anti-inflammatory pharmacological activity of tranilast suggests its potential clinical application for allergic diseases complicated with inflammation.