Differential cytokine expression in myocytes and non-myocytes after myocardial infarction in rats.
The proinflammatory cytokines interleukin (IL)-1beta and IL-6 are increased after acute myocardial infarction (MI). Moreover, serum IL-6 level is elevated after MI, but has also been associated with heart failure. In the present study, heart function was monitored in a rat model of chronic MI. Cytokine expression in the infarcted and non-infarcted myocardium as well as in hearts of sham-operated controls was measured by the ribonuclease-protection assay. To identify the cells contributing to the increased cytokine expression, we further analyzed myocytes and non-myocytes isolated in the acute phase as well as during congestive heart failure (CHF) after MI. There was a strong induction in cytokine expression in the myocytes of the infarct area 6 h after MI. In the non-infarcted myocardium, cytokine expression increased only slightly in the non-myocytes after 6 h. This was not different from sham-operated controls and may, therefore, be induced by stress and catecholamines. In CHF, however, cytokine expression level in myocytes was normal. It increased slightly but significantly in the non-myocytes 4 and 8 weeks after MI. In conclusion, we suggest that pro-inflammatory cytokines, produced by the ischemic myocytes may be involved in the initiation of wound healing of the necrotic area, whereas the effect of pro-inflammatory cytokines in CHF, if any, seems not to be crucial.
Deten
Alexander
A
Carl-Ludwig-Institute of Physiology, University of Leipzig, Leipzig, Germany. deta@medizin.uni-leipzig.de
Volz
Hans Christian
HC
Briest
Wilfried
W
Zimmer
Heinz-Gerd
HG
D000818:Animals; D016207:Cytokines / Q000235:genetics*; D004195:Disease Models, Animal; D005260:Female; D020869:Gene Expression Profiling; D006439:Hemodynamics; D007375:Interleukin-1 / Q000235:genetics; D015850:Interleukin-6 / Q000235:genetics; D009203:Myocardial Infarction / Q000139:chemically induced / Q000235:genetics*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D032383:Myocytes, Cardiac / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
D016207:Cytokines; D007375:Interleukin-1; D015850:Interleukin-6; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha