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The term tropic is from Ancient Greek τροπικός (tropikós), in the sense "of or pertaining to a turn or change", meaning "causing a change, affecting"; this is the same origin as tropic and trope. This should not be confused with trophic, as in similar-sounding trophic hormone – the words and concepts are both unrelated. [3]
Trophic hormones can be found in body systems including the endocrine, gastrointestinal, urinary, and nervous systems. The term trophic is from Ancient Greek τροφικός ( trophikós ) meaning "pertaining to food or nourishment", here used to mean "growth"; this is the same origin as atrophy .
If there is an excess of growth hormone, it is usually because of over-secretion of somatotrope cells in the anterior pituitary gland. A significant amount of excess somatotrope secretion before puberty or before the end of new bone tissue growth can lead to gigantism, a disease that causes excess growth of body (e.g. being over 7 ft. tall) and unusually long limbs.
Releasing hormones and inhibiting hormones are hormones whose main purpose is to control the release of other hormones, either by stimulating or inhibiting their release. They are also called liberins ( / ˈ l ɪ b ə r ɪ n z / ) and statins ( / ˈ s t æ t ɪ n z / ) (respectively), or releasing factors and inhibiting factors .
The migration of the growth cone is mediated through the interaction of numerous trophic and tropic factors; netrins, slits, ephrins and semaphorins are four well-studied tropic cues . The growth cone is capable of modifying its sensitivity to these guidance molecules as it migrates to its target; this sensitivity regulation is an important ...
A prolactin cell (also known as a lactotropic cell, epsilon acidophil, lactotrope, lactotroph, mammatroph, mammotroph) is a cell in the anterior pituitary which produces prolactin (a peptide hormone) in response to hormonal signals including dopamine (which is inhibitory), thyrotropin-releasing hormone and estrogen (especially during pregnancy), which are stimulatory.
The hypothalamus produces the hormones oxytocin and vasopressin in its endocrine cells (left). These are released at nerve endings in the posterior pituitary gland and then secreted into the systemic circulation. The hypothalamus releases tropic hormones into the hypophyseal portal system to the anterior pituitary (right).
The following is a list of hormones found in Humans. Spelling is not uniform for many hormones. For example, current North American and international usage uses [citation needed] estrogen and gonadotropin, while British usage retains the Greek digraph in oestrogen and favours the earlier spelling gonadotrophin.