MMP2 and endothelial dysfunction: The AoSMCs, isolated from spontaneously hypertensive rats with endothelial dysfunction and co-cultured with ECs, exhibited exacerbated calcification and higher expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) than those cultured without ECs, confirming the ability of ECs to promote calcification in this setting [44].