Paricalcitol is a vitamin D receptor agonist. It is used for the prevention and treatment of secondary hyperparathyroidism associated with chronic renal failure.

Paricalcitol (30 nM; HP + PC) produces a significant reduction in calcification relative to the observed in cells in HP medium. Paricalcitol causes a reduction in the levels of nuclear β-catenin to a level similar to that observed in control cells [1].

Paricalcitol (300 ng/kg/day) significantly decreases Tau and prevents LV dysfunction in mice. It reduces mRNA expression of ANP, fibronectin and collagen III in the TAC-pari mice [2].

After TAC or sham surgery, a subset of the mice is treated with paricalcitol which activates the VDR, at a final dose of 300 ng/kg/day. Paricalcitol is dissolved in a 95% propylene glycol and 5% ethyl alcohol solution. Mice were intraperitoneally injected with paricalcitol (or vehicle only) three times per week on Monday, Wednesday, and Friday for five consecutive weeks. An established anti-hypertrophic and anti-fibrotic treatment, namely the angiotensin II receptor blocker (ARB) losartan is also included. Previous experiments have shown it is feasible and efficacious to dissolve losartan in the drinking water at a concentration of 30 mg/kg/day; mice are treated for five consecutive weeks. So, in total eight groups are studied. Sham (n=10), TAC (n=10), Sham + losartan (Sham-los, n=10), TAC + losartan (TAC-los, n=10), Sham + paricalcitol (Sham-pari, n=10), TAC + paricalcitol (TAC-pari, n=10), Sham + paricalcitol + losartan (Sham-combi, n=10) and TAC + paricalcitol + losartan (TAC-combi, n=10) [2].