User:Cvcorle/sandbox

Local hormones are a large group of signaling molecules that do not circulate within the blood. Local hormones are produced by nerve and gland cells and bind to either neighboring cells or the same type of cell that produced them. Local hormones are activated and inactivated quickly. They are released during physical work and exercise. They mainly control smooth and vascular muscle dilation. Strength of response is dependent upon the concentration of receptors of target cell and the amount of ligand ( the specific local hormone).

Eicosanoids (ī′kō-să-noydz; eicosa = twenty, eidos = formed) are a primary type of local hormone. These local hormones are formed by a chain of 20 amino acids and fatty acids from phospholipids in the cell membrane. There are two main types of eicosanoids: prostaglandins and leukotrienes, which initiate either autocrine stimulation or paracrine stimulation. Ecosanoids are the result of a ubiquitous pathway which first produces arachidonic acid, and then the ecosanoid product.

Prostaglandins are the most diverse category of eicosanoids and are thought to be synthesized in most tissues of the body. This type of local hormone stimulates pain receptors and increases the inflammatory response. Nonsteroidal anti-inflammatory drugs stop the formation of prostaglandins, thus inhibiting these responses.

Leukotrienes are a type of ecosanoids that are produced in leukocytes and function in inflammatory mediation.

Paracrines (para- = beside or near) are local hormones that involve cell-cell communication to act on neighboring cells. This type of signaling involves the secretion of paracrine factors, which travel a short distance in the extracellular environment to effect nearby cells. These factors can be excitatory or inhibitory. There are a few families of factors that are very important in embryo development including fibroblast growth factor (FGF), the Hedgehog family, the Wnt family, and the TGF-β superfamily.

Autocrines (auto- = self) are local hormones that act on the same cell that secreted them.

Juxtacrines ( juxta = near) are local hormones that require close contact and act on either the cell which emitted them or on adjacent cells.

Autacoids are biologically functional signaling molecules which act like local hormones and are linked to inflammatory responses and pain.

Gastrin family[edit]

The Gastrin family is a group of peptides evolutionarily similar in structure and function. Commonly synthesized in antroduodenal G-cells. Regulate gastric function along with gastric acid secretion and mucosal growth.

1. Gastrin
2. Cholecystokinin (CCK)

Secretin family[edit]

The Secretin family are peptides that act as local hormones which regulate regulate activity of G-protein coupled receptors. Most often found in the pancreas and the intestines. Secretin was discovered in 1902 by E. H. Starling. It was later linked to chemical regulation and was the first substance to be deemed a hormone.

1. Secretin
2. Glucagon
3. Glicentin (GLI)
4. Vasoactive intestinal peptide (VIP)
5. Gastric inhibitory polypeptide (GIP)

References[edit]

4.Salmon, John A; Higgs, Gerald A (1987). "Prostaglandins and leukotrienes as inflammatory mediators". British Medical Bulletin. 43 (2): 285–96. PMID 2825898

5. SF Gilbert. (2000). Developmental Biology 6th Edition.

6. Jan M. Keppel Hesselink.(2016). "Autacoids: A New Fundament for Pain Medicine of the 21th Century".

7. Rehfeld JF1, Friis-Hansen L, Goetze JP, Hansen TV. (2007). "The biology of cholecystokinin and gastrin peptides". Curr Top Med Chem. 2007;7(12):1154-65.

8. Henriksen JH, de Muckadell OB. (2000). "Secretin, its discovery, and the introduction of the hormone concept.". Scand J Clin Lab Invest. 2000 Oct;60(6):463-71.

9. Mark H. Whitnall, William G. Haynes, David J. Webb (1997). Principles of Medical Biology.