Background: In our study we used immunohistochemical technique to demonstrate the presence of the cytokines tumour necrosis factor alpha (TNF-α), interleukin 1beta (IL-1β), transforming growth factor beta1 (TGF-β1) and intercellular adhesion molecule-1 (ICAM-1) in porcine coronaries even in physiological conditions.
Materials and methods: Inflammatory cytokines are polypeptide mediators which act as a communication signal between immune system cells and other types of cellsin different organs and tissues, both in human and pig coronary circulation.
Results: Our results show that pro-inflammatory cytokines TNF-α, IL-1β, TGF-β1 and ICAM-1 are also present in the medium tunica of the coronary arteries under physiological conditions. These results may be compared with those found in coronary atherosclerosis, where the increase in TNF-α has a dramatic effect on the function of the left ventricle, and the high value of IL-1 correlates directly with the extent of myocardial necrosis. In our study we observe the damage and activation of endothelial cells; this induces endothelial dysfunction by accumulation and oxidation of low density lipoproteins (LDL). The formation of oxidized LDL could play a central role in the amplification of the inflammatory response causing an increased expression of pro-inflammatory cytokines which promotes leukocyte recruitment in the intimal layer. These leukocytes, after the adhesion to the endothelium, penetrate the intimate tunic.
Conclusions: Therefore inflammatory processes promote the onset and evolution of atheroma and the development of thrombotic complications.
Keywords: ICAM-1; IL-1beta; TGF-beta1; TNF-alpha; cytokines; porcine coronary arteries.