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Parathyroid Hormone (PTH)

What is Parathyroid Hormone (PTH)?

Parathyroid hormone (PTH) is a key regulator of calcium metabolism in the body. It is secreted by the parathyroid glands—four small glands located adjacent to the thyroid gland in the neck. PTH plays a vital role in maintaining balanced levels of calcium, phosphate, and vitamin D in the bloodstream.

How PTH Regulates Calcium Levels

PTH acts on multiple organs to elevate blood calcium levels when they fall below normal. It works by:

Stimulating the release of calcium from bones

Enhancing calcium absorption in the intestines (through activation of vitamin D)

Increasing calcium reabsorption in the kidneys

At the same time, PTH promotes phosphate excretion and boosts the production of active vitamin D (calcitriol), which is essential for healthy bones and calcium absorption.

Hormonal Feedback Mechanism

The secretion of PTH is tightly controlled by calcium levels in the blood. When calcium is low, the parathyroid glands release more PTH. When calcium levels are high, PTH production is reduced. This feedback loop helps maintain optimal calcium balance in the body.

Conditions Linked to Abnormal PTH Levels

Abnormal parathyroid hormone levels can indicate a variety of medical conditions:

Elevated PTH levels may suggest primary hyperparathyroidism, a disorder where one or more parathyroid glands are overactive. This leads to high calcium levels (hypercalcaemia), which can cause symptoms such as kidney stones, bone pain, fatigue, and muscle weakness.

Low PTH levels can indicate hypoparathyroidism, a condition in which the glands produce too little PTH. This results in low calcium levels (hypocalcaemia), potentially leading to muscle cramps, tingling, or more severe complications.

PTH Blood Testing in Slough

For individuals in Slough and surrounding Berkshire areas, PTH blood testing is a valuable tool for assessing calcium imbalances and identifying underlying parathyroid or metabolic disorders. If you're experiencing symptoms such as fatigue, bone pain, or abnormal calcium levels, local diagnostic clinics in Slough offer reliable parathyroid hormone testing to support timely diagnosis and effective treatment.