parafollicular cell

anatomy

Also known as: C cell

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June 23, 2026

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Parafollicular cells, also known as C cells, are primarily found in the thyroid gland in humans and other mammals. These cells synthesize and secrete the hormone calcitonin. Calcitonin's main function is to lower the concentration of calcium and phosphorus in the blood when these levels rise above normal. It achieves this by inhibiting the breakdown of bone tissue and reducing the reabsorption of calcium in the kidneys, leading to increased calcium excretion in urine. The effects of calcitonin are opposite to those of parathyroid hormone, which raises blood calcium levels. In nonmammalian vertebrates, calcitonin is produced by the ultimobranchial bodies. Synthetic calcitonin is used in treating osteoporosis.123

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calcitonin
…and other mammals primarily by parafollicular cells (C cells) in the thyroid gland. In birds, fishes, and other nonmammalian vertebrates, calcitonin is secreted by cells of the glandular ultimobranchial bodies. The overall effect of calcitonin is to lower the concentration of calcium in the blood when it rises above the…
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…and other mammals primarily by parafollicular cells (C cells) in the thyroid gland. In birds, fishes, and other nonmammalian vertebrates, calcitonin is secreted by cells of the glandular ultimobranchial bodies. The overall effect of calcitonin is to lower the concentration of calcium in the blood when it rises above the…
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medullary thyroid carcinoma
…thyroid carcinoma, tumour of the parafollicular cells (C cells) of the thyroid gland. It occurs both sporadically and predictably, affecting multiple members of families who carry gene mutations associated with the disease. In some families medullary thyroid carcinomas are the only tumours that appear, whereas in other families medullary thyroid…
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…thyroid carcinoma, tumour of the parafollicular cells (C cells) of the thyroid gland. It occurs both sporadically and predictably, affecting multiple members of families who carry gene mutations associated with the disease. In some families medullary thyroid carcinomas are the only tumours that appear, whereas in other families medullary thyroid…
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thyroid gland
The thyroid gland and calcitonin
…produce calcitonin, which are called C cells, or parafollicular cells arise, separately from the thyroid and migrate into it during development of the embryo. The C cells end up nestled in the spaces between the follicles. Because these cells have a separate embryological origin from the thyroid follicular cells,and because…
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…produce calcitonin, which are called C cells, or parafollicular cells arise, separately from the thyroid and migrate into it during development of the embryo. The C cells end up nestled in the spaces between the follicles. Because these cells have a separate embryological origin from the thyroid follicular cells,and because…
Read More