Pituitary Glossary starting with G

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An element used in contrast media for magnetic resonance imaging.

A metal element that is used in magnetic resonance imaging (MRI) and other imaging methods. It is a contrast agent, which helps show abnormal tissue in the body during imaging with a special machine. Gadolinium texaphyrin is a substance that is being studied in the treatment of cancer. It may make tumor cells more sensitive to radiation therapy, improve tumor images using magnetic resonance imaging (MRI), and kill cancer cells. It is a type of metalloporphyrin complex. Also called motexafin gadolinium.


A frame housing the x-ray tube, collimators, and detectors in a CT machine, with a large opening into which the patient is inserted.

Part of a CT scanning machine – During a CT scan, the patient will be asked to lie on a narrow table (gantry) that slides into the center of the scanner.

Gastrointestinal (GI)

Relating to the stomach and intestines.

The gastrointestinal system consists of the gastrointestinal tract, a tube extending from the mouth to the anus; its purpose is to break down food, prepare it for absorption and eliminate waste.


Nonproprietary, or not protected by trademark registration.

A drug not protected by a trademark. Also, the scientific name as opposed to the proprietary, brand name.


The beginning of a process.

The beginning or origin; into being of something; the process or mode of origin.

Genetic Engineering

A variety of techniques that molecular biologists use to manipulate DNA molecules to study the expression of a gene.

A laboratory technique sometimes used to identify a defective gene in an unborn child which may cause a particular disease.


Glomerular filtration rate.

GFR is a calculation of how efficiently the kidneys are filtering wastes from the blood. A traditional GFR calculation requires an injection into the bloodstream of a substance that is later measured in a 24-hour urine collection. Recently, scientists found they could calculate GFR without an injection or urine collection. The new calculation requires only a measurement of the creatinine in a blood sample.
Creatinine is a waste product in the blood created by the normal breakdown of muscle cells during activity. Healthy kidneys take creatinine out of the blood and put it into the urine to leave the body. When kidneys are not working well, creatinine builds up in the blood.


Growth Hormone, secreted by the pituitary gland; the major hormone responsible for height growth

Also plays a role in maintenance of bone density in adults, body composition in that it builds muscle and breaks down fat, regulates lipids, and may play a role in cardiovascualr health.


Growth hormone releasing hormone.

GHRH, or growth hormone releasing hormone is a hypothalamic peptide that regulates the synthesis and secretion of growth hormone in the anterior pituitary gland.
The growth hormone (GH) stimulation test measures the level of growth hormone (GH) in the blood after you receive arginine or GH-releasing hormone. The test measures the ability of the pituitary gland to release GH.


Growth hormone release inhibiting hormone (same as SRIF)

Somatostatin inhibits growth hormone release in response to GHRH


Growth hormone releasing peptide.

Growth hormone releasing peptide (GHRP-6) is a synthetic hexapeptide which specifically stimulates secretion of growth hormone.


An organ of the body that produces materials (hormones) released into the bloodstream, such as the pituitary or pineal gland. Hormones influence metabolism and other body functions.

Endocrine glands include the Adrenals, Hypothalamus, Islets of Langerhans in the pancreas, Ovaries, Parathyroids, Pineal, Pituitary, Testes, and Thyroid

Glucagon Test

Glucagon is a hormone that is produced by cells in the pancreas the function of which is to raise blood sugar.

An alternative to the insulin tolerance test; used to test for normal function of the hypothalamus and pituitary gland; glucagon increases blood sugar levels, causing a number of hormones (e.g., growth hormone and cortisol) to be released in response.


Medications used to decrease swelling around tumors. Medication to duplicate the effects of cortisol.

Often used to treat adrenal insufficiency.


A type of sugar found in the blood; an important source of energy in the body.

Aldohexose occurring as the D form and found as a free monosaccharide in fruits and other parts of plants and in the normal blood of all animals; the end product of carbohydrate metabolism and the chief source of energy for most living organisms.

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