Corticotropin-releasing hormone: A hormone made by the hypothalamus that stimulates the release of corticotropin by the anterior pituitary gland. Corticotropin-releasing hormone is abbreviated and often referred to as CRH.
CRH is chemically classed as a neuropeptide hormone — a protein-like molecule made up of a short chain of amino acids produced in the brain that functions as a hormone.
The hypothalamus where CRH is produced is an area of the brain that also controls body temperature, hunger, and thirst.
The anterior pituitary where CRH acts is the front portion of the pituitary, a small gland in the head. It secretes hormones that influence growth, sexual development, skin pigmentation, and thyroid function, as well as the function of the adrenal cortex.
Prodded by CRH, the anterior pituitary releases corticotropin which travels down to the adrenal cortex (the outer part of the adrenal gland), stimulating its growth and its secretion of corticosteroids (cortisone-like hormones). Corticotropin is also called adrenocorticotropic hormone (ACTH).
CRH is normally released by the mother and the embryo soon after the embryo implants in the uterus (womb). The function of the CRH appears to protect the embryo from immunologic rejection by the mother. Without CRH, the embryo may be rejected by the mother, resulting in a miscarriage (spontaneous abortion).
Cortisol: A metabolite of the primary stress hormone cortisone. Cortisol is an essential factor in the proper metabolism of starches, and it is the major natural glucocorticoid (GC) in humans.
Cosmid: DNA from a bacterial virus into which is spliced a small fragment of a genome to be amplified and sequenced. A cosmid is an artificially constructed structure. It is used in cloning (copying) pieces of DNA. (On a technical level, a cosmid contains the cos gene of phage lambda and can be packaged in […]
- Costal margin
Costal margin: The lower edge of the chest (thorax), formed by the bottom edge of the rib cage.
Inflammation and swelling of the cartilage of the chest wall, usually involving the cartilage that surrounds the breastbone (sternum) but sometimes including the adjacent tip of a rib. Costochondritis causes local pain and tenderness of the chest around the sternum. Treatment options include anti-inflammatory medications and, in severe cases, corticosteroid injections. Also known as Tietze […]
Cotinine: The major metabolite (breakdown product) of nicotine. Exposure to nicotine can be measured by analyzing the cotinine level in the blood, saliva, or urine. Since nicotine is highly specific to tobacco smoke, serum cotinine levels track exposure to tobacco smoke and its toxic constituents. Cotinine assays provide an objective quantitative measure that is more […]