*2.3. Capillary Rarefaction*

Endothelial cells line blood or lymphatic vessels and are the most abundant cells of the non-myocyte fraction in murine hearts [6,7]. The medial layer of small and large vessels consists of vascular smooth muscle cells (VSMCs). Endothelial dysfunction is frequent in CKD [32] and can be considered an early manifestation of coronary vascular disease [33]. Endothelial dysfunction leads to disturbed microcirculation and is considered an independent risk factor for cardiovascular events [33,34]. CKD-induced microangiopathy has been shown to lead to tissue hypoxia and dysfunctional angiogenesis [33].
