What is the Difference Between Calcitonin and Parathyroid Hormone?

Calcitonin and parathyroid hormone (PTH) are two hormones that play crucial roles in regulating calcium levels in the body. However, they have different functions and effects on calcium homeostasis:

1. Origin: PTH is released from the parathyroid glands, while calcitonin is released from thyroid C-cells.
2. Function: PTH increases calcium levels in the body by activating osteoclasts (cells involved in bone resorption) and absorbing calcium in the kidneys. Calcitonin, on the other hand, lowers calcium levels by inhibiting osteoclasts. It is also involved in the regulation of phosphate levels.
3. Potency: Calcitonin is weaker than PTH, and it seems to have a less significant role in regulating blood calcium levels than PTH. High or low levels of PTH can cause hypercalcemia or hypocalcemia, respectively, which can lead to serious conditions. In contrast, having high or low levels of calcitonin doesn't have much of an effect on the body.
4. Relationship: The relationship between calcitonin and PTH is complex, but when the body has the right level of calcium, calcitonin and PTH can coexist.

In summary, calcitonin and PTH both help regulate calcium levels in the body, but they function differently and have varying effects on calcium homeostasis. PTH increases calcium levels, while calcitonin decreases them, and PTH appears to have a more important role in regulating blood calcium levels than calcitonin.

Comparative Table: Calcitonin vs Parathyroid Hormone

Calcitonin and parathyroid hormone (PTH) are both involved in regulating calcium metabolism in the body, but they have opposing effects on calcium levels and bone-related processes. Here is a table highlighting the differences between calcitonin and parathyroid hormone:

Both hormones regulate calcium metabolism in the body and are involved in maintaining normal levels of calcium in the blood.