Failure to reduce experimental myocardial infarct size with ibuprofen pre-treatment in rats.

The prophylactic role of ibuprofen in experimental myocardial infarction has not been reported. Twenty-four rats pre-treated with ibuprofen (30 mg/kg), po, for 21 days were subjected to myocardial infarction by administration of isoprenaline hydrochloride (85 mg/kg), sc, on two consecutive days. An equal number of rats were given saline to serve as control. Heart specimens were taken for macroscopic and microscopic examination after 1 day, 5 days, 12 days and 21 days, following myocardial infarction. Ibuprofen pre-treatment caused a significant increase in infarct size at all the intervals studied (P less than 0.01), indicating that ibuprofen exerted a harmful effect in increasing the size of experimental myocardial infarction.