What is Vitamin D's net effect?
Where does activation (hydroxylation) of Vitamin D3 occur?
What else is needed to get Calcitriol?
To increase the plasma Ca AND phosphate concentrations.
It occures in the Liver at eh 25th position.yeilding 25, hydroxyvitamin D3
This PTH stimulates this to be activated in the KIDNEY at position 1 --> Calcitriol.