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Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine
Published on: July 7, 2016
Effect of phenoxybenzamine on indomethacin induced systemic vasoconstriction in dogs
Abstract:
The effect of phenoxybenzamine (PBZ) on indomethacin (IM) induced systemic vasoconstriction was studied in 22 dogs using a right heart bypass procedure which allowed for control of cardiac output. Indomethacin alone (n = 8) caused an increase in mean arterial pressure (MAP) from 71 +/- 6.5 mmHg to 116 +/- 7.6 mmHg (p less than .05). In PBZ pretreated dogs (n = 8), the increase in MAP was from 49 +/- 3.4 mmHg to 80 +/- 6.8 mmHg (p less than .05). In 3 dogs given PBZ alone, MAP fell from 81 +/- 7.3 mmHg to 42 +/- 3.8 mmHg (p less than .05). In 3 untreated dogs, MAP fell from 86 +/- 4.1 mmHg to 63 +/- 9.0 mmHg. Thus, IM causes vasoconstriction in the systemic circulation of the dog, and this effects does not appear to be mediated by alpha adrenergic stimulation.
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