On the back of the thyroid gland are tiny endocrine glands called parathyroid glands. Notwithstanding their diminutive size, these glands are essential for controlling calcium levels, which are necessary for bone health, muscle contraction, and nerve function. The four tiny, pea-shaped glands in the neck that make parathyroid hormone (PTH) are called parathyroid glands. The balance of calcium and phosphate in the blood and bones is controlled by this hormone.
Table of Contents
Structure :
1. Location
- In the neck, behind the thyroid gland, there are normally two pairs of parathyroid glands (superior and inferior).
- There may be differences in quantity and location.
2. Composition:
- Composed of oxyphil cells, which have a less clear function, and chief cells, which generate PTH.
3. Blood Supply:
- Richly vascularized, with the inferior thyroid artery serving as its main source of blood.
Function of Parathyroid Gland :
The preservation of calcium homeostasis is the parathyroid gland’s main job. By secreting parathyroid hormone (PTH), which acts on three main sites, it accomplishes this:
1. Bones:
- Encourages the breakdown of bone tissue by osteoclasts, which releases calcium into the bloodstream.
2. Kidneys:
- Reduces calcium loss through urine by increasing calcium reabsorption.
- Encourages vitamin D activation, which improves the gut’s absorption of calcium.
3. Intestines:
- Stimulates the synthesis of active vitamin D (calcitriol), which indirectly improves the absorption of calcium from the diet.
Importance of the Parathyroid Glands
The body’s calcium and phosphate balance, which is necessary for the healthy operation of the neurological, muscular, and skeletal systems, is maintained in large part by the parathyroid glands. These glands are essential for preserving general health and averting major imbalances, despite their diminutive size.
1. Regulation of Blood Calcium Levels
Calcium Homeostasis:
- Parathyroid hormone (PTH), which is secreted by the parathyroid glands, aids in preserving the blood’s ideal calcium levels.
- Blood coagulation, muscle contractions, and nerve signal transmission all depend on calcium.
- Averts diseases such as hypercalcemia (high calcium levels) and hypocalcemia (low ones).
2. Bone Health
Calcium Release and Deposition:
- The exchange of calcium between the blood and bones is controlled by PTH.
- When calcium levels are low, it stimulates osteoclast activity to release calcium.
- Ensures bone density and strength by assisting in the maintenance of the equilibrium between bone formation and resorption.
3. Kidney Function:
Calcium Reabsorption:
- PTH decreases calcium loss in urine by increasing calcium reabsorption in the kidneys.
Phosphate Excretion:
- Encourages phosphate excretion, avoiding imbalances that might cause tissues or bones to become calcified.
4. Vitamin D Activation
- PTH encourages the kidneys to produce calcitriol, the active form of vitamin D, from inactive forms.
- In order to ensure adequate dietary calcium uptake, active vitamin D improves intestinal calcium absorption.
5. Nervous System Support
- The parathyroid glands’ regulation of calcium is essential for:
- Nerve impulse transmission.
- Preserving muscle and nerve cell excitability.
Disorders:
Calcium and phosphate imbalances are caused by disorders of the parathyroid glands, which are caused by either an excess or a shortage of parathyroid hormone (PTH). These disorders can have a major effect on kidney function, neuromuscular activity, and bone health.
1. Hyperparathyroidism
- PTH overproduction results in higher blood calcium levels.
- Bone pain, kidney stones, exhaustion, and depression are among the symptoms.
2. Hypoparathyroidism:
- Low calcium levels are caused by insufficient PTH secretion.
- Brittle nails, tingling, seizures, and cramping in the muscles are some of the symptoms.
3. Parathyroid Tumors:
- Hormonal imbalances may result from adenomas, which are typically benign.
Conclusion:
Despite being tiny and frequently overlooked in favor of the thyroid, the parathyroid glands are crucial for preserving calcium and phosphate balance. Strong bones, effective nerve transmission, and normal muscle contraction are all guaranteed by the proper operation of these glands. Their critical role in the endocrine system is highlighted by the fact that parathyroid disorders can result in serious health problems.
Frequently Asked Questions (FAQ)
What is the main function of the parathyroid glands?
To use parathyroid hormone (PTH) to control blood and bone calcium and phosphate levels.
What happens if the parathyroid glands malfunction?
Calcium imbalances brought on by malfunction can result in problems like weak bones, kidney stones, muscle spasms, or exhaustion.
How are parathyroid disorders treated?
Medication, calcium/vitamin D supplements, or surgery to remove overactive glands are some of the treatment options.