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Corticotropin-releasing hormone (CRH) also known as corticotropin-releasing factor (CRF) or corticoliberin is a peptide hormone and neurotransmitter involved in the stress response. It is a releasing hormone that belongs to corticotropin-releasing factor family. In humans, it is encoded by the ''CRH'' gene.〔 Its main function is the stimulation of the pituitary synthesis of ACTH, as part of the HPA Axis. Corticotropin-releasing hormone (CRH) is a 41-amino acid peptide derived from a 196-amino acid preprohormone. CRH is secreted by the paraventricular nucleus (PVN) of the hypothalamus in response to stress. Increased CRH production has been observed to be associated with Alzheimer's disease and major depression, and autosomal recessive hypothalamic corticotropin deficiency has multiple and potentially fatal metabolic consequences including hypoglycemia.〔 In addition to being produced in the hypothalamus, CRH is also synthesized in peripheral tissues, such as T lymphocytes, and is highly expressed in the placenta. In the placenta, CRH is a marker that determines the length of gestation and the timing of parturition and delivery. A rapid increase in circulating levels of CRH occurs at the onset of parturition, suggesting that, in addition to its metabolic functions, CRH may act as a trigger for parturition.〔(【引用サイトリンク】 url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=1392 )〕 A recombinant version for diagnostics is called corticorelin (INN). ==Hormonal actions== CRH is produced by parvocellular neuroendocrine cells within the paraventricular nucleus of the hypothalamus and is released at the median eminence from neurosecretory terminals of these neurons into the primary capillary plexus of the hypothalamo-hypophyseal portal system. The portal system carries the CRH to the anterior lobe of the pituitary, where it stimulates corticotropes to secrete adrenocorticotropic hormone (ACTH) and other biologically-active substances (β-endorphin). ACTH stimulates the synthesis of cortisol, glucocorticoids, mineralocorticoids and DHEA.〔(【引用サイトリンク】url=http://www.yourhormones.info/hormones/corticotrophinreleasing_hormone.aspx )〕 In the short term, CRH can suppress appetite, increase subjective feelings of anxiety, and perform other functions like boosting attention. Although the distal action of CRH is immunosuppression via the action of cortisol, CRH itself can actually heighten inflammation, a process being investigated in multiple sclerosis research. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Corticotropin-releasing hormone」の詳細全文を読む スポンサード リンク
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