KDR and diabetes mellitus: Based on these data, we developed an in vitro model of diabetic-PAD, wherein HUVECs were challenged with HSS in the presence of palmitic acid (PA, as an in vitro model for diabetes) to determine an EC-specific role of VEGF165b-VEGFR1 signaling in regulating angiogenesis in a pathologically relevant in vitro model with impaired VEGFR2 signaling.