Parathyroid Hormone (PTH)
Parathyroid Hormone (PTH): Overview and Function
Definition
Parathyroid hormone (PTH), also known as parathormone, is a peptide hormone secreted by the parathyroid glands. It plays a critical role in regulating serum calcium levels in the blood, which is essential for various physiological functions, including muscle contraction, nerve transmission, and bone health.
Function of Parathyroid Hormone
PTH maintains calcium homeostasis through its effects on three primary target organs: bones, kidneys, and the intestines.
- Mechanism: PTH stimulates osteoclast activity indirectly by binding to osteoblasts, which increases the expression of RANKL (Receptor Activator of Nuclear factor Kappa-B Ligand). This process promotes the differentiation of osteoclast precursors into mature osteoclasts that resorb bone tissue, releasing calcium into the bloodstream.
- Effect: Increases serum calcium levels by mobilizing calcium from the bone reservoir.
- Mechanism: PTH enhances calcium reabsorption in the renal tubules, particularly in the distal convoluted tubule and collecting ducts. It also decreases phosphate reabsorption in the proximal tubule.
- Effect: Reduces urinary calcium excretion while increasing phosphate excretion, contributing to elevated serum calcium levels.
- Mechanism: PTH stimulates the conversion of vitamin D to its active form (calcitriol) in the kidneys. Active vitamin D promotes intestinal absorption of calcium and phosphate from dietary sources.
- Effect: Increases dietary calcium absorption, further supporting serum calcium levels.
Regulation of PTH Secretion
PTH secretion is primarily regulated by serum calcium levels through a negative feedback mechanism:
- Low Calcium Levels: When blood calcium levels drop, parathyroid cells detect this change via calcium-sensing receptors and increase PTH secretion.
- High Calcium Levels: Elevated blood calcium levels inhibit PTH release, reducing its effects on bone resorption and renal reabsorption.
Clinical Relevance
Disorders related to PTH can lead to significant health issues:
- Hyperparathyroidism: Excessive production of PTH can result in hypercalcemia (high blood calcium levels), leading to symptoms such as kidney stones, osteoporosis, and abdominal pain.
- Hypoparathyroidism: Insufficient PTH production can cause hypocalcemia (low blood calcium levels), resulting in muscle cramps, seizures, and tingling sensations.
Conclusion
Parathyroid hormone is essential for maintaining calcium homeostasis in the body, influencing bone health, kidney function, and intestinal absorption of nutrients.
How DrStemCellsThailand’s Anti-Aging and Regenerative Medicine Center Can Help
At DrStemCellsThailand‘s Anti-Aging and Regenerative Medicine Center of Thailand, we understand the critical role that parathyroid hormone plays in overall health. Our team specializes in advanced diagnostic evaluations to assess parathyroid function and related disorders. We offer innovative regenerative therapies aimed at restoring hormonal balance and improving calcium metabolism. By utilizing personalized treatment plans tailored to your specific needs, we aim to address conditions such as hyperparathyroidism or hypoparathyroidism effectively. If you are experiencing symptoms related to parathyroid dysfunction or have concerns about your calcium levels, consult with our specialists today to explore how our cutting-edge therapies can enhance your health and well-being.
