The research protocol must give a clear indication of what follow up will be provided to the research participants and for how long. This may include a follow u, especially for adverse events, even after data collection for the research study is completed.
The two most important hormones for maintaining calcium levels in the body are parathyroid hormone (PTH) and 1,25(OH)2D (the active form of vitamin D).The major regulator is PTH, which is part of a negative feedback loop to maintain [Ca ++ ] ECF (see Humoral regulation).he two most important hormones for maintaining calcium levels in the body are parathyroid hormone (PTH) and 1,25(OH)2D (the active form of vitamin D).
Vitamin D also is involved in regulating the amount of calcium in your blood. Normally, this balancing act works well. When calcium levels in your blood fall too low, your parathyroid glands secrete enough PTH to restore the balance. PTH raises calcium levels by releasing calcium from your bones and increasing the amount of calcium absorbed from your small intestine. When blood-calcium levels are too high, the parathyroid glands produce less PTH. But sometimes one or more of these glands produce too much hormone, leading to abnormally high levels of calcium (hypercalcemia) and low levels of phosphorus in your blood.