doiSerbia

Cytohistological and immunohistochemical characteristics of vascular remodelling in diseases of the blood vessels

Lačković Vesna (School of Medicine, Institute of Histology and Embryology, Belgrade)
Vuković Irena (School of Medicine, Institute of Histology and Embryology, Kragujevac)

INTRODUCTION. Vascular remodelling is an adaptive process involving the adjustment of the structure and function of blood vessels to long-term changes in haemodynamic conditions. This process leads to structural alterations within vessel walls in different cardiovascular diseases, such as hypertension, atherosclerosis, and coarctation of the aorta. OBJECTIVE. We investigated the histochemical and immunocytochemical characteristics of morphological lesions in coronary atherosclerosis and coarctation of the aorta. METHOD. Twenty-one samples of atherosclerotically modified right coronary arteries, divided into 6 segments, were analysed. We also examined 10 samples of coarctation segments, excised during surgery. The segments were stained histochemically (using orcein and alcian blue-PAS), immunocytochemically (using α-smooth muscle actin-α-SMA, vimentin, desmin, myosin heavy chains-MHC, CD3, CD45, S-100, and Proliferating Cell Nuclear Antigen-PCNA), and for electron microscopy. RESULTS. The results of our study of morphological lesions in coronary atherosclerosis demonstrated initial functional and then, in the later stages of atherosclerosis, morphological, damage to the endothelium. The preatheroma stage revealed the presence of intimal dedifferentiation of smooth muscle cells, with the expression of vimentin and α-SMA, and the lack of expression of desmin. Along with these changes, a huge number of foam cells of variant origin were noticed. Some of them were CD68-immunoreactive while others were both vimentin- and S-100-immunoreactive. All examined samples of the coarctation of the aorta demonstrated the presence of dedifferentiated smooth muscle cells as well as a diminution in cell numbers, followed by apoptotic smooth muscle cells, and the absence of inflammatory cells. CONCLUSION. Some foam cells develop from monocytemacrophage lineage (CD68-immunoreactive), while others originate from smooth muscle cells (vimentin and S-100- immunoreactive). Coarctation of the aorta is characterised by a diminution in cell numbers (apoptosis) as well as their dedifferentiation from contractile to synthetic phenotype.

Keywords: atherosclerosis, coarctation, smooth muscle cells, intimal thickening