U50,488H inhibits neutrophil accumulation and TNF-α induction induced by ischemia-reperfusion in rat heart

► The role of the κ-opioid receptor was studied in an ischemia-reperfusion heart model. ► Reduction was seen in infarction area, myeloperoxidase, CK, and TNF-α production. ► Effects were related to an increase in NO production via a PI3K sensitive pathway.