Editing Hormone (section)

==Regulation==
The rate of hormone biosynthesis and secretion is often regulated by a [[homeostasis|homeostatic]] [[negative feedback]] control mechanism. Such a mechanism depends on factors that influence the [[metabolism]] and [[excretion]] of hormones. Thus, higher hormone concentration alone cannot trigger the negative feedback mechanism. Negative feedback must be triggered by overproduction of an "effect" of the hormone.<ref>{{cite book | vauthors = Campbell M, Jialal I | chapter = Physiology, Endocrine Hormones |date=2019 |url=http://www.ncbi.nlm.nih.gov/books/NBK538498/ | title = StatPearls |publisher=StatPearls Publishing |pmid=30860733|access-date=13 November 2019 }}</ref><ref>{{cite journal | vauthors = Röder PV, Wu B, Liu Y, Han W | title = Pancreatic regulation of glucose homeostasis | journal = Experimental & Molecular Medicine | volume = 48 | issue = 3 | pages = e219 | date = March 2016 | pmid = 26964835 | pmc = 4892884 | doi = 10.1038/emm.2016.6 }}</ref>
[[File:Negative Feedback Gif.gif|thumb|Blood glucose levels are maintained at a constant level in the body by a negative feedback mechanism. When the blood glucose level is too high, the pancreas secretes insulin and when the level is too low, the pancreas then secretes glucagon. The flat line shown represents the homeostatic set point. The sinusoidal line represents the blood glucose level.]]
Hormone secretion can be stimulated and inhibited by:
* Other hormones (''stimulating''- or ''releasing'' -hormones)
* Plasma concentrations of ions or nutrients, as well as binding [[globulin]]s
* [[Neuron]]s and mental activity
* Environmental changes, e.g., of light or temperature

One special group of hormones is the [[tropic hormone]]s that stimulate the hormone production of other [[endocrine system|endocrine glands]]. For example, [[thyroid-stimulating hormone]] (TSH) causes growth and increased activity of another endocrine gland, the [[thyroid]], which increases output of [[thyroid hormone]]s.<ref name="Shah, Shilpa Bhupatrai. 2012">{{Cite book|title=Allergy-hormone links| vauthors = Shah SB, Saxena R |date=2012 |publisher= Jaypee Brothers Medical Publishers (P) Ltd |isbn=978-93-5025-013-6 |location=New Delhi |oclc=761377585 }}</ref>

To release active hormones quickly into the [[circulatory system|circulation]], hormone biosynthetic cells may produce and store biologically inactive hormones in the form of [[prehormone|pre-]] or [[prohormone]]s. These can then be quickly converted into their active hormone form in response to a particular stimulus.<ref name="Shah, Shilpa Bhupatrai. 2012"/>

[[Eicosanoid]]s are considered to act as local hormones. They are considered to be "local" because they possess specific effects on target cells close to their site of formation. They also have a rapid degradation cycle, making sure they do not reach distant sites within the body.<ref>"Eicosanoids". www.rpi.edu. Retrieved 2017-02-08.</ref>

Hormones are also regulated by receptor agonists. Hormones are ligands, which are any kinds of molecules that produce a signal by binding to a receptor site on a protein. Hormone effects can be inhibited, thus regulated, by competing ligands that bind to the same target receptor as the hormone in question. When a competing ligand is bound to the receptor site, the hormone is unable to bind to that site and is unable to elicit a response from the target cell. These competing ligands are called antagonists of the hormone.<ref name="Silverthorn_2016">{{Cite book|title=Human physiology : an integrated approach| vauthors = Silverthorn DU, Johnson BR, Ober WC, Ober CW |isbn=978-0-321-98122-6|edition=Seventh|location= San Francisco | publisher = Pearson |oclc=890107246|year = 2016}}</ref>