parathyroid gland

(noun)

One of four endocrine glands situated in the neck, usually on the posterior surface of the thyroid gland, that produce parathyroid hormone.

Related Terms

Examples of parathyroid gland in the following topics:

  • Overview of the Parathyroid Glands

    • The parathyroid glands are small endocrine glands in the neck that produce parathyroid hormone.
    • The parathyroid glands are small endocrine glands—approximately the size of a grain of rice—in the neck that produce parathyroid hormone.
    • The two parathyroid glands on each side that are positioned higher are called the superior parathyroid glands, while the lower two are called the inferior parathyroid glands.
    • Parathyroid glands control the amount of calcium in the blood and within the bones.
    • The parathyroid gland in relation to the thyroid gland.

  • Parathyroid Hormone

    • The parathyroid glands are small, pea-sized endocrine glands located on the rear side of the thyroid gland.
    • The major function of the parathyroid glands is to maintain the body's calcium level within a very narrow range, so that the nervous and muscular systems, which depend on calcium to transmit action potentials, can function properly.
    • When blood calcium levels drop below a certain point, the calcium-sensing receptors in the parathyroid gland are activated, and the parathyroid glands release parathyroid hormone (PTH) into the blood.
    • This interaction between parathyroid hormone and calcitonin is also an important part of bone remodeling.
    • Parathyroid hormone regulates the levels of calcium in the blood. to the parathyroid glands.

  • Parathyroid Gland Disorders

    • Many conditions are associated with disorders of the function of the parathyroid gland .
    • Often, these "localizing" tests used to "find" the bad parathyroid gland are not successful in locating which parathyroid gland has become a tumor.
    • The use of ultrasound-guided FNA, and parathyroid hormone washings can confirm the abnormal glands.
    • Hypoparathyroidism is decreased function of the parathyroid glands with under production of parathyroid hormone.
    • The parathyroid gland in relation to the thyroid gland.

  • Bone Tissue and the Effects of Aging

    • Calcium-sensing membrane receptors in the parathyroid gland monitor calcium levels in the extracellular fluid.
    • Low levels of calcium stimulate the release of parathyroid hormone (PTH) from chief cells of the parathyroid gland.
    • High levels of calcium in the blood, on the other hand, lead to decreased PTH release from the parathyroid gland.

  • Overview of Endocrine Glands

    • A collection of endocrine glands makes up the endocrine system: the pituitary (anterior and posterior lobes), thyroid, parathyroid, adrenal (cortex and medulla), pancreas and gonads.
    • There are four parathyroid glands, all located on the thyroid gland.
    • All four glands also secrete parathyroid hormone, or PTH, which causes calcium to be released from the bones back into the extracellular fluid.
    • The adrenal glands are a pair of ductless glands located above the kidneys.
    • Differentiate among the types of endocrine glands (pituitary [posterior pituitary, anterior pituitary], thyroid, parathyroid, adrenal, and pancreas) in the endocrine system

  • Bone and Calcium Homeostasis

    • Calcium release from bone is regulated by parathyroid hormone.
    • When blood calcium concentration rises, the parafollicular cells of the thyroid gland increase calcitonin secretion into the blood.
    • At the same time, the parathyroid glands reduce parathyroid hormone secretion into the blood.

  • Calcium and Phosphate Balance Regulation

    • Absorption is controlled by vitamin D while excretion is controlled by parathyroid hormones.
    • However, the distribution from bone to plasma is controlled by both the parathyroid hormones and vitamin D.
    • It is the ionized calcium concentration that is monitored by the parathyroid gland and if low, parathyroid hormone secretion is increased.
    • Any excess is excreted by the kidney and this excretion is increased by the parathyroid hormone.
    • Plasma phosphate has no direct effect on parathyroid hormone secretion; however, if it is elevated it combines with Ca++, decreasing ionized Ca++ in plasma, and thereby increasing parathyroid hormone secretion.

  • Development of the Endocrine System

    • The main endocrine glands are the hypothalamus (neuroendocrine gland), pituitary (anterior and posterior lobes), thyroid, parathyroid, adrenal (cortex and medulla), pancreas, and gonads.
    • Pineal gland 2.
    • Pituitary gland 3.
    • Thyroid gland 4.
    • Adrenal gland 6.

  • Action of Thyroid Hormones

    • Triiodothyronine (T3) and thyroxine (T4) are enzymes produced by the thyroid gland.
    • Calcitonin is another hormone released by the thyroid gland that is responsible for modulating blood calcium levels in conjunction with parathyroid hormone, which is released from the parathyroid.

  • Mammary Glands

    • All the milk-secreting tissue leading to a single lactiferous duct is called a simple mammary gland; a complex mammary gland is all the simple mammary glands serving one nipple.
    • Humans normally have two complex mammary glands, one in each breast, and each complex mammary gland consists of 10–20 simple glands.
    • Mammary glands develop during different growth cycles.
    • In this stage, mammary gland development depends on systemic (and maternal) hormones, but is also under the local regulation of paracrine communication between neighboring epithelial and mesenchymal cells by parathyroid hormone-related protein.
    • Cross-section of the mammary-gland. 1.