Question: what is the difference between calcitonin and procalcitonin?
Answer: Procalcitonin. Procalcitonin (PCT) is a peptide precursor of the hormone calcitonin, synthesized by the parafollicular cells of the thyroid gland, and involved in calcium homeostasis. The major function of calcitonin is to decrease calcium absorption by osteoclastic cells, which increases circulating calcium levels.