Comparison of Adenine-Induced Rat Models for Vascular Calcification in Chronic Kidney Disease

Vascular calcification significantly contributes to cardiovascular complications and limb loss in chronic kidney disease (CKD). To establish an optimal rat model for vascular calcification, we tested varying adenine concentrations and feeding durations in Sprague–Dawley rats (n = 72), divided into six groups (n = 12 each). The control group received a standard diet for 18 weeks. Group 1 was given 0.5% adenine for 4 weeks, followed by a standard diet. Group 2 received 0.5% adenine for 4 weeks, then 0.25% for 14 weeks. Group 3A received 0.5% adenine for 12 weeks and then standard diet; group 3B received 0.5% adenine for 12 weeks, followed by 0.25% for 6 weeks; group 3C received 0.5% adenine for 18 weeks. At week 18, vascular calcification was absent in the control and group 1. Groups 2 and 3A showed low incidence (12.5%), while groups 3B and 3C showed high incidence (66.7%). However, survival rates differed: 75.0% in 3B and 50.0% in 3C after 12 wk. Thus, 0.5% adenine for 12 weeks followed by 0.25% for 6 weeks effectively induced vascular calcification while maintaining acceptable survival, providing a practical model for studying CKD-related vascular pathology.