Modification by indomethacin of the blood pressure lowering effect of pindolol and propranolol in conscious rabbits.

In conscious rabbits, the intravenous administration of pindolol (0.125 mg/kg) and propranolol (1 mg/kg) induced a highly significant (p less than 0.001) decrease of mean arterial blood pressure and with propranolol, a significant (p less than 0.01) bradycardia. In the same model the intravenous administrtion of saline (1 ml/kg) and of indomethacin (1 mg/kg) did not affect mean arterial blood pressure or heart rate (p greater than 0.3). Pretreatment of the animals with indomethacin (1 mg/kg) abolished the effect of both beta-blockers on mean arterial blood pressure (p greater than 0.05) and had no significant effect on heart rate.