U cilju brzog oslobađanja aktivnih hormona u [[Cirkulatorni sistem|krvotok]], ćelije biosintetičkih hormona mogu proizvoditi i čuvati biološke neaktivne hormone u vidu pre- ili prohormona. Ovi potom mogu brzo biti, kao rezultat odgovarajućih stimulansa, konvertovani u svoje aktivne forme hormona.
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.
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
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.
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.
[[Eicosanoids]] are considered to act as local hormones.
== Receptori ==