Patient/caregiver was instructed upon regulation of serum calcium as follows:
- The serum calcium levels are regulated primarily by two hormones, parathyroid hormone and calcitonin.
- Also, vitamin D3 or calcitriol, contributes significantly to the regulation of the serum calcium levels.
- Low levels of serum calcium in the body stimulate increased synthesis of parathyroid hormone by the parathyroid glands. Increased parathyroid hormone secretion results in resorption of the bone and consequently, leads to mobilization of calcium and phosphorus from the bone into the blood, thus helping to offset the low levels of serum calcium.
- Low levels of serum calcium in the body with consequent stimulation of increased parathyroid hormone synthesis stimulate increased synthesis of calcitriol in the body. Calcitriol helps with increased intestinal absorption of calcium and phosphorus from the food. Calcitriol also helps with reabsorption of calcium in the kidneys. Both these actions of calcitriol help with maintaining optimal concentrations of serum calcium and phosphorus.
- Restoration of serum calcium and phosphorus levels to normal, reduces the activity of parathyroid hormone and calcitriol.
- Elevated levels of serum calcium stimulate synthesis of calcitonin from the thyroid gland. Calcitonin inhibits resorption of bone, thus inhibiting the migration of calcium from the bone into the blood. Calcitonin also promotes bone formation, by increasing the deposition of calcium into the bone, thus contributing to a net increase in bone mass and a reduction in serum calcium levels. Calcitonin also promotes renal excretion of calcium and phosphorus, thus helping to regulate elevated serum calcium towards optimal.
