VDR and secondary hyperparathyroidism: With respect to hypertension and the renin–angiotensin–aldosterone system (RAAS) activation, it has, however, been criticized that in VDR-null mice fed a normal diet, the changes may be due to secondary hyperparathyroidism and that VDR knock-out mice fed the so-called “rescue diet” enriched with calcium, phosphate, and lactose, which normalizes mineral homeostasis in these mice, did not show increased mean arterial pressure or RAAS activation [14].