Calcium regulation hormone
- Calcium regulation in the body is tightly controlled by a complex interaction of hormones.
- These hormones work together to ensure a delicate balance between calcium absorption, storage, and excretion.
- The following hormones are involved in calcium regulation.
- Parathyroid Hormone (PTH):
- The parathyroid gland produces parathyroid hormone.
- It plays a central role in calcium regulation.
- When blood calcium levels drop below the normal range, PTH is released.
- Parathyroid hormone acts on the bones, kidneys, and intestines to increase calcium levels.
- Calcitonin:
- Calcitonin is produced by the thyroid gland.
- It has the opposite effect of parathyroid hormone.
- When blood calcium levels are too high, calcitonin is released, helping to lower calcium levels.
- Estrogen and Testosterone:
Sex hormones, such as estrogen in females and testosterone in males, influence calcium regulation:
- Estrogen:
- Estrogen enhances calcium absorption in the intestines.
- Promotes the deposition of calcium in bone.
- Inhibits the activity of osteoclasts.
- Testosterone:
- Testosterone also helps in maintaining bone health by promoting bone mineralization and reducing bone turnover.
- Glucocorticoids:
- Glucocorticoid hormones, such as cortisol, can have significant effects on calcium regulation.
- Prolonged exposure to high levels of glucocorticoids can lead to increased calcium excretion, decreased calcium absorption in the intestines, and bone loss.
- Thyroid Hormones:
- Thyroid hormones, including triiodothyronine (T3) and thyroxine (T4), indirectly influence calcium homeostasis.
- They increase the sensitivity of tissues to Parathyroid hormone, thereby enhancing the actions of PTH on bone and kidneys.
- Imbalances in calcium-regulating hormones:
Imbalances in calcium-regulating hormones can lead to various disorders like:
- Hypoparathyroidism is characterized by inadequate parathyroid hormone synthesis which results in low blood calcium levels.
- Hyperparathyroidism is a condition of overproduction of parathyroid hormone which leads to higher blood calcium levels and increased bone resorption.
In conclusion, calcium regulation in the body is a complex process involving multiple hormones including
- Parathyroid hormone
- Calcitonin
- Vitamin D
- Sex hormones
| Hormone |
Function |
Source |
| Thyroid Hormones |
· Increase sensitivity of tissues to parathyroid hormone (PTH) |
· Thyroid gland
|
| Vitamin D |
· Increases intestinal calcium absorption |
· Sunlight exposure
· Dietary sources |
| Parathyroid Hormone |
· Stimulates calcium release from bones
· Enhances calcium reabsorption in kidneys
· Increases intestinal absorption |
· Parathyroid glands
|
| Calcitonin |
· Inhibits bone breakdown
· Promotes calcium excretion in the urine |
· Thyroid gland |
| Estrogen |
· Enhances calcium absorption, promotes bone deposition
· Inhibits bone breakdown |
· Ovaries (in females)
· Adrenal glands
· Fat cells |
| Testosterone |
· Promotes bone mineralization
· Reduces bone turnover |
· Testes (in males)
· Adrenal glands |
| Glucocorticoids
|
· Can lead to increased calcium excretion
· Decreased calcium absorption in the intestines and bone loss |
· Adrenal glands
|
