the parathyroid gland Flashcards
which hormone does the parathyroid hormone secrete
the parathyroid hormone
what is PTH
parathyroid hormone
what is the secretion of parathyroid hormone stimulated by
decrease in blood calcium levels
what is the parathyroid hormone a regulator of
blood calcium levels
what does parathyroid hormone regulate
serum calcium and phosphate levels
what are the three main effects of the parathyroid hormone
promotion of the absorption of calcium from the small intestine
increasing renal tubular reabsorption of calcium ions
increased osteoclastic resorption leading to promoted bone breakdown
what are the two main disorders of the parathyroid glands
hypoparathyroidism and hyperparathyroidism
describe hyperparathyroidism
this is excessive production of parathyroid hormone which is commonly caused by parathyroid adenomas and leads to excessive osteoclastic erosion of bone, leading to hypercalcaemia where there is too much calcium in the blood
what are the symptoms of hyperparathyroidism
bone pain and increased risk of kidney stones
what is hypoparathyroidism
when there is little to no PTH being produced and usually occurs due to the removal of parathyroid glands
what is secondary hyperparathyroidism
this is a response of all the parathyroid glands to a persistent low calcium level in the blood which leads to a feedback mechanism whereby the parathyroids become enlarged and secrete excess parathyroid hormone in an attempt to increase calcium levels again
what divides the parenchyma into nodules of secretory cells
delicate septa which carry blood vessels lymphatics and nerves
what are the glandular cells of this gland
chief cells and oxyphil cells
describe chief cells
small, with round central nuclei and a clear cytoplasm that synthesise and secrete the parathyroid hormone
