Structural and functional peculiarities of the endothelium of heart vessels of mature rats according to immunistochemical studies

The relevance of the study is connected with the modern point of view that endothelial dysfunction may be the cause of such socially significant diseases as atherosclerosis, diabetes, varicose veins, etc. The aim of the work is to study the morphofunctional peculiarities of the endothelium of the cardiovascular vessels of the mature rat using Willebrand factor (vWF) immunohistochemistry. Material and methods. We used mature Wistar rats (n = 12). Polyclonal rabbit antibodies were used for the immunohistochemical detection of vWF. The reaction was carried out on paraffin sections, made through the whole heart. Results. It was shown that the immunopositive reaction to vWF (vWF+ ) in the endothelium of different regions of the rat heart is not uniform. A tendency was found to weaken the vWF+ reaction in the direction from the base of the heart to its apex. Most functionally active endothelial cells with signs of exocytosis were observed in the aortic root, the large coronary arteries of the epicardium, the fibrous ring, the valves and the subaortal cone. vWF+ was less pronounced in the endothelium lining the atrial and ventricular cavities and in the myocardial capillaries. Conclusions. Using immunohistochemical detection of the vWF, the endothelium features of different parts of the rat heart were identified. Structural features due to increased secretion of vascular endothelial cells of the heart were revealed. Further research in this direction may be important to explain the mechanisms and diagnosis of endothelial dysfunction.