Rabbit Anti-Human Thyroid hormone polyclonal antibody for IHC-P. Parathyroid hormone is secreted by parathyroid cells. This hormone elevates blood Ca2+ levels by dissolving the salts in bone and preventing their renal excretion. Defects in this gene are a cause of familial isolated hypoparathyroidism (FIH) . Most PTH is secreted in its intact, mature 9.5 kDa form, amino acids 1-84; however, it can also be secreted as N-terminal truncated fragments or C-terminal fragments after intracellular degradation, as in case of hypercalcemia. No PTH fragment has been found to be the result of another gene or alternative splicing of the PTH gene.