| anterior pituitary-like hormone | A glycoprotein with a carbohydrate fraction composed of d-galactose and hexosamine, extracted from the urine of pregnant women and produced by the placental trophoblastic cells; its most important role appears to be stimulation, during the first trimester, of ovarian secretion of the oestrogen and progesterone required for the integrity of conceptus; it appears to play no significant role in the last two trimesters of pregnancy, as the oestrogen and progesterone are then formed by the placenta. Synonym: anterior pituitary-like hormone, choriogonadotropin, chorionic gonadotropic hormone, chorionic gonadotrophic hormone, placenta gonadotropin, placentagonadotropin. (05 Mar 2000) |
|---|---|
| receptors, pituitary hormone | Cell surface proteins that bind pituitary hormones with high affinity and trigger intracellular changes influencing the behaviour of cells. Since many pituitary hormones are also released by neurons as neurotransmitters, these receptors are also found in the nervous system. (12 Dec 1998) |
| receptors, pituitary hormone-regulating hormone | Cell surface receptors that bind the hypothalamic hormones regulating pituitary cell differentiation, proliferation, and hormone synthesis and release, including the pituitary-releasing and release-inhibiting hormones. The pituitary hormone-regulating hormones are also released by cells other than hypothalamic neurons, and their receptors also occur on non-pituitary cells, especially brain neurons, where their role is less well understood. Receptors for dopamine, which is a prolactin release-inhibiting hormone as well as a common neurotransmitter, are not included here. (12 Dec 1998) |
| pharyngeal pituitary | The embryonic remnant of the oral end of Rathke's pouch that is cut off from the adenohypophysis by the developing sphenoid bone; composed chiefly of chromophobes and, under normal conditions, considered physiologically inactive. See: hypophysis. (05 Mar 2000) |
| pituitary | <anatomy, endocrinology> An endocrine gland located at the base of the brain, in the small recess of a bone - certain sections of the pituitary each secretes important hormones including growth hormone (GH) and antidiuretic hormone (ADH). (16 Dec 1997) |
| pituitary adamantinoma | <oncology, tumour> A form of primary brain tumour which develops in the pituitary gland. These tumours often secrete increased quantities of pituitary hormones (for example growth hormone) which can result in conditions such as gigantism and acromegaly. They are often benign and rare and comprise less than 5% of childhood brain tumours. Other symptoms include vision changes, headache and weight gain. Treatment often includes a combination of surgery and radiation therapy. (27 Sep 1997) |
| pituitary adenoma | <radiology> Benign, slow-growing, arises from adenohypophysis (anterior lobe), 5-18% of all intracranial neoplasms plain film (unreliable): enlargement of sella and sloping of the sella floor, erosion of the anterior and posterior clinoid, erosion of the dorsum sellae, calcified in less than10%, may present as a mass in the nasopharynx functioning microadenoma, less than10 mm, 20-30% of pituitary adenomas, types: prolactinoma, corticotrophic adenoma, somatotrophic adenoma, nonfunctioning macroadenoma, more than 10 mm, 70-80% of pituitary adenomas (12 Dec 1998) |
| pituitary-adrenal system | The interactions between the anterior pituitary and adrenal glands, in which corticotropin (acth) stimulates the adrenal cortex and adrenal cortical hormones suppress the production of corticotropin by the anterior pituitary. (12 Dec 1998) |
| pituitary ameloblastoma | <oncology, tumour> A form of primary brain tumour which develops in the pituitary gland. These tumours often secrete increased quantities of pituitary hormones (for example growth hormone) which can result in conditions such as gigantism and acromegaly. They are often benign and rare and comprise less than 5% of childhood brain tumours. Other symptoms include vision changes, headache and weight gain. Treatment often includes a combination of surgery and radiation therapy. (27 Sep 1997) |
| pituitary apoplexy | Sudden haemorrhage into or ischemic necrosis of a normal or adenomatous pituitary gland. (12 Dec 1998) |
| pituitary cachexia | Anterior pituitary insufficiency due to trauma, vascular lesions, or tumours; usually developing postpartum as a result of pituitary necrosis caused by ischemia during a hypotensive episode during delivery; characterised clinically by asthenia, loss of weight and body hair, arterial hypotension, and manifestations of thyroid, adrenal, and gonadal hypofunction. Synonym: hypophysial cachexia, pituitary cachexia. (05 Mar 2000) |
| pituitary diverticulum | A tubular outgrowth of ectoderm from the stomodeum of the embryo; it grows dorsad toward the infundibular process of the diencephalon, around which it forms a cup-like mass, giving rise to the pars distalis and pars juxtaneuralis of the hypophysis. Synonym: craniopharyngeal canal, hypophyseal pouch, Rathke's diverticulum, Rathke's pocket, Rathke's pouch. (05 Mar 2000) |
| pituitary dwarf | Dwarfism as result of failure of growth hormone production because of hypothalamic or pituitary abnormality. Synonym: pituitary dwarf. (05 Mar 2000) |
| pituitary dwarfism | Short stature due to underpreformance of the pituitary gland (specifically of the anterior pituitary). (12 Dec 1998) |
| pituitary fossa | Fossa of the sphenoid bone housing the pituitary gland. See: sella turcica. Synonym: fossa hypophysialis, pituitary fossa. (05 Mar 2000) |