Clenbuterol enhances the production of kynurenic acid in brain cortical slices and glial cultures.

The effect of a beta(2)-adrenergic agonist, clenbuterol on the production of a glutamate receptor antagonist, kynurenic acid was studied in vitro. Clenbuterol enhanced the production of kynurenic acid in brain cortical slices (0.1-1.0 mM) and in glial cultures (1-50 muM). Timolol, a non-selective beta-adrenergic antagonist prevented this effect. The presented data indicate a novel mechanism of action of beta(2)-adrenoceptor agonists and suggest that an increased formation of the endogenous glutamate receptor antagonist, kynurenic acid could partially contribute to their neuroprotective activity.