The sections in this article are:
Physiological Effects of Vitamin D and its Active Metabolites on Calcium and Phosphorus Homeostasis
Sources of Vitamin D
Transport of Vitamin D and its Metabolites in Plasma
Metabolism of Vitamin D
3
to 25‐Hydroxyvitamin D
3
Metabolism of 25‐Hydroxyvitamin D
3
Regulation of the 25‐Hydroxyvitamin D
3
–1α‐Hydroxylase Enzyme
Parathyroid Hormone
Phosphorus Concentrations
Calcium: Direct Effects
1,25‐Dihydroxyvitamin D
3
Calcitonin
Hydrogen Ion
Sex Steroids
Glucocorticoids
Pituitary Hormones
Thyroid Hormone
Pregnancy
Catabolism of 1,25‐Dihydroxyvitamin D
3
Physiological Adaptations that Occur in Response to Changes in Serum Calcium and Phosphate Concentrations
Hypocalcemia and Hypercalcemia
Hypophosphatemia and Hyperphosphatemia
Pathophysiology and Physiology of the 1,25‐Dihydroxyvitamin D
3
System
Mechanisms of Action of 1,25‐Dihydroxyvitamin D
3
1,25‐Dihydroxyvitamin D
3
in the Intestine
Processes in the Cell That Are Mediated by 1,25‐Dihydroxyvitamin D
3
Intestinal Brush Border Events Induced by 1,25‐Dihydroxyvitamin D
3
Events at the Contraluminal Border
Effects of 1,25‐Dihydroxyvitamin D
3
on the Intestinal Cell
1,25‐Dihydroxyvitamin D
3
in the Kidney