Parathyroid Gland
The parathyroid glands secrete parathyroid hormone (PTH), which is the primary regulator of calcium and phosphate homeostasis.
What our notes say
- The parathyroid glands secrete parathyroid hormone (PTH), which is the primary regulator of calcium and phosphate homeostasis. (ENDOCRINE PATHOLOGY)
- This is due to autonomous overproduction of PTH by one or more parathyroid glands. (ENDOCRINE PATHOLOGY)
- Chief cells are the predominant and functional cells of the parathyroid gland, responsible for PTH synthesis and secretion. (ADRENAL NEOPLASMS — Adenoma vs Carcinoma)
- Chief cells are the predominant and functional cells of the parathyroid gland, primarily responsible for PTH synthesis and secretion. (ADRENAL NEOPLASMS — Adenoma vs Carcinoma)
- Chief cells predominate and are the functional cells of the parathyroid gland. (ADRENAL NEOPLASMS — Adenoma vs Carcinoma)
- PTH is secreted by parathyroid glands in response to low serum calcium (inverse relationship) (Chemical Pathology Practice Examination)
Study material on Parathyroid Gland
- ADRENAL NEOPLASMS — Adenoma vs Carcinoma
- ADRENAL NEOPLASMS — Adenoma vs Carcinoma
- Embryology — Past Paper Questions & Answers
- Pituitary + Thyroid & Parathyroid
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Practice questions on Parathyroid Gland
The two superior and two inferior parathyroid glands are found adjacent to the posterior aspect of the thyroid gland. From which of the following are these parathyroid glands derived in embryologic development?
- Foramen cecum
- Mandibular swellings
- Maxillary processes
- Pharyngeal pouches
- Thyroglossal duct
Answer: D. The fourth pouches give rise to the superior pair of parathyroid glands and the parafollicular C cells within the thyroid; the third pouch gives rise to the inferior parathyroids and the non-lymphoid cells of the thymus. ---
Parathyroid glands are embryologically derived from
- Pharyngeal pouches (3rd and 4th)
- Neuroectoderm
- Mesoderm
- Rathke's pouch
Answer: A. Superior parathyroids derive from the 4th pharyngeal pouch, inferior parathyroids from the 3rd pharyngeal pouch (same as thymus). This explains why ectopic parathyroid tissue can be found in the mediastinum alongside ectopic thymic tissue. ---
The predominant cell type in parathyroid glands responsible for PTH secretion is
- Stromal fat cells
- Oxyphil cells
- Chief cells
- Water-clear cells
Answer: C. Chief cells are the main PTH-secreting cells. They have pale cytoplasm and round nuclei. Oxyphil cells appear after puberty, have abundant mitochondria, and their function is unclear. Fat cells make up ~50% of normal parathyroid stroma in adults. ---