Description:
Calcitriol  is a metabolite of the secosteroid vitamin D3. This hormone stimulates intestinal calcium transport at a much higher rate than vitamin D3 and hydroxy D3, and is considered to represent the biologically active form of vitamin D3. In addition to regulating the movement of calcium in the blood and bone, 1α,25-Dihydroxyvitamin D3 participates in developmental regulation and signaling. It stimulates an increase in protein kinase C levels with an effect on the regulation of c-myc transcription and activation of Raf kinase. 1α,25-Dihydroxyvitamin D3 is shown to increase the synthesis of prostacyclin with a correlated increase in cyclooxygenase activity, indicating a further role in vascular regulation. 1α,25-Dihydroxyvitamin D3 (Calcitriol) is an activator of PKC and VDR.