Effect of indomethacin on cardiac beta-adrenergic receptors.

Treatment of rats with indomethacin, 1.5 mg/kg per day, for one week, significantly reduced the number of beta-adrenoceptors in the heart without altering their affinity for the specific beta-adrenergic ligand. In indomethacin-treated rats there was a reduction in the cardiac response to epinephrine in vivo as indicated by a shift to the right of the epinephrine dose-heart rate response curve. These results support a possible interference by indomethacin in beta-adrenoceptor-mediated effects.