ENDOGENOUS CYTOKINE ANTAGONISTS DURING MYOCARDIAL-ISCHEMIA AND THROMBOLYTIC THERAPY

We tested the idea that cytokine antagonists are released during acute myocardial ischemia to counteract proinflammatory effects of cytokine s. We investigated changes in plasma concentrations of the anticytokin e molecules alpha-melanocyte-stimulating hormone (alpha-MSH), interleu kin-1 receptor antagonist (IL-1ra), and soluble tumor necrosis factor receptor (sTNFr) in patients with acute myocardial infarction (AMI) or unstable angina (UA). Blood samples were collected at presentation in the coronary care unit, at 3-hour intervals for 24 hours, and daily f or 4 days thereafter. There were no significant differences in the con centrations of cytokine antagonists in patients with AMI or UA. Howeve r, whereas concentrations of alpha-MSH were increased in early samples of patients with AMI or UA who were treated with a thrombolytic agent , they were consistently low in untreated patients. IL-1ra re concentr ations likewise were greater 3 and 6 hours after treatment in patients who underwent thrombolysis, whereas there was no significant differen ce in plasma sTNFr between the two groups. We suggest that during myoc ardial ischemia and thrombolysis anticytokine molecules released from the injured myocardium become available to reduce inflammation caused by cytokines and other mediators of inflammation.