Inhibition of IgE-mediated N-acetylglucosaminidase and serotonin release from rat basophilic leukemia cells (RBL-2H3) by tenidap: a novel anti-inflammatory agent.

Tenidap [(Z)-5-chloro-2,3-dihydro-3-(hydroxy-2-thienylmethylene)-2-oxo-1H- indole-1-carboxamide] is a novel anti-inflammatory compound of the oxindole class that currently is undergoing clinical evaluation in man. Here we demonstrate that tenidap inhibits (IC50 = approximately 10 microM) IgE-mediated secretion of granule constituents from the rat mast cell tumor line RBL-2H3. The inhibitory effect is rapid in onset, readily reversible, and appears to be unique when compared to a representative selection of other acidic (carboxylic acids, pyrazoles and oxicams) nonsteroidal anti-inflammatory compounds.