Information about Paracrine
Paracrine signaling is a form of cell signaling in which the target cell is close to ("para" = alongside of or next to, but this strict prefix definition is not meticulously followed here) the signal releasing cell.
The signal chemical is called the paracrine agent.
The distinction is sometimes made between paracrine and autocrine signaling. In both types of signalling, the signal is limited to other cells in the local area. However, paracrine signalling affects cells of a different type than the cell performing the secretion, while autocrine signaling affects cells of the same type.
Alternatively, the signal may only reach nearby cells for one of the following reasons:
In mature organisms paracrine signaling functions include responses to allergens, repairs to damaged tissue, formation of scar tissue, and clotting.
Overproduction of some paracrine growth factors has been linked to the development of cancer.
Other examples of paracrine agents are somatostatin and histamine.
For example, testosterone secreted from the testes acts in an endocrine manner to stimulate peripheral events (e.g. muscle growth), and in a paracrine manner to stimulate spermatogenesis in the adjacent seminiferous tubules.
The signal chemical is called the paracrine agent.
The distinction is sometimes made between paracrine and autocrine signaling. In both types of signalling, the signal is limited to other cells in the local area. However, paracrine signalling affects cells of a different type than the cell performing the secretion, while autocrine signaling affects cells of the same type.
Reasons for degradation
Sometimes, the reason that the effects are limited to a local area is because the signal chemical is broken down too quickly to be carried to other parts of the body.Alternatively, the signal may only reach nearby cells for one of the following reasons:
- (1) the nearby cells take up the signal at a very high rate, leaving little signal free to travel further.
- (2) the signal gets stuck in the extracellular-matrix, or structure surrounding the signal releasing cell, and thus the signal is unable to travel far from the signal releasing cell.
Examples
Examples of paracrine signaling agents include growth factor and clotting factors. Growth factor signalling plays an important role in many aspects of development.In mature organisms paracrine signaling functions include responses to allergens, repairs to damaged tissue, formation of scar tissue, and clotting.
Overproduction of some paracrine growth factors has been linked to the development of cancer.
Other examples of paracrine agents are somatostatin and histamine.
Autocrine and endocrine actions
Some paracrine agents also have autocrine, intracrine or endocrine actions as well.For example, testosterone secreted from the testes acts in an endocrine manner to stimulate peripheral events (e.g. muscle growth), and in a paracrine manner to stimulate spermatogenesis in the adjacent seminiferous tubules.
See also
External links
- MeSH Paracrine+Signaling
- Paracrine at eMedicine Dictionary
- p_04/12611500 at Dorland's Medical Dictionary
- -1335164869 at GPnotebook
Cell physiology: cell signaling | |
|---|---|
| Key concepts | Ligand - Cell signaling networks - Signal transduction - Apoptosis - Second messenger system (Ca2+ signaling, Lipid signaling) |
| Processes | Paracrine - Autocrine - Juxtacrine - Neurotransmitters - Endocrine (Neuroendocrine) |
| Types of proteins | Receptor (Transmembrane, Intracellular) - Transcription factor (General, Preinitiation complex, TFIID, TFIIH) - Adaptor protein |
Cell signaling is part of a complex system of communication that governs basic cellular activities and coordinates cell actions. The ability of cells to perceive and correctly respond to their microenvironment is the basis of development, tissue repair, and immunity as well as
..... Click the link for more information.
..... Click the link for more information.
Para may refer to:
..... Click the link for more information.
- Para-, in English, is an affix of ancient Greek and Latin origin
- Para Dog-faced Bat, a bat species from South and Central America
- Para Loga, one among the seven Logas (seven upper worlds) in Ayyavazhi mythology
..... Click the link for more information.
Autocrine signalling is a form of hormonal signalling in which a cell secretes a hormone, or chemical messenger (called the autocrine agent) that binds to autocrine receptors on the same cell, leading to changes in the cell.
..... Click the link for more information.
..... Click the link for more information.
extracellular matrix (ECM) is the extracellular part of animal tissue that usually provides structural support to the cells in addition to performing various other important functions. The extracellular matrix is the defining feature of connective tissue in animals.
..... Click the link for more information.
..... Click the link for more information.
The term growth factor refers to a naturally occurring protein capable of stimulating cellular proliferation and cellular differentiation. Growth factors are important for regulating a variety of cellular processes.
..... Click the link for more information.
..... Click the link for more information.
Coagulation is a complex process by which blood forms solid clots. It is an important part of hemostasis (the cessation of blood loss from a damaged vessel) whereby a damaged blood vessel wall is covered by a platelet- and fibrin-containing clot to stop bleeding and begin repair of
..... Click the link for more information.
..... Click the link for more information.
allergen.[1]
Sensitivities vary from one person to another and it is possible to be allergic to an extraordinary range of substances.
..... Click the link for more information.
Sensitivities vary from one person to another and it is possible to be allergic to an extraordinary range of substances.
Types of allergies
..... Click the link for more information.
Scar tissue can refer to:
..... Click the link for more information.
- Granulation tissue, a product of healing in major wounds
- Scar Tissue, a Red Hot Chili Peppers song
- Scar Tissue (book), the autobiography of Anthony Kiedis, lead singer of the Red Hot Chili Peppers
..... Click the link for more information.
Coagulation is a complex process by which blood forms solid clots. It is an important part of hemostasis (the cessation of blood loss from a damaged vessel) whereby a damaged blood vessel wall is covered by a platelet- and fibrin-containing clot to stop bleeding and begin repair of
..... Click the link for more information.
..... Click the link for more information.
Editing of this page by unregistered or newly registered users is currently disabled due to vandalism.
If you are prevented from editing this page, and you wish to make a change, please discuss changes on the talk page, request unprotection, log in, or .
..... Click the link for more information.
If you are prevented from editing this page, and you wish to make a change, please discuss changes on the talk page, request unprotection, log in, or .
..... Click the link for more information.
Somatostatin (also known as growth hormone inhibiting hormone (GHIH) or somatotropin release-inhibiting hormone (SRIF)) is a peptide hormone that regulates the endocrine system and affects neurotransmission and cell proliferation via interaction with
..... Click the link for more information.
..... Click the link for more information.
Histamine is a biogenic amine involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter.[1] New evidence also indicates that histamine plays a role in chemotaxis of white blood cells.
..... Click the link for more information.
..... Click the link for more information.
Autocrine signalling is a form of hormonal signalling in which a cell secretes a hormone, or chemical messenger (called the autocrine agent) that binds to autocrine receptors on the same cell, leading to changes in the cell.
..... Click the link for more information.
..... Click the link for more information.
Intracrine refers to a hormone that acts inside a cell. Steroid hormones act through intracellular (mostly nuclear) receptors and are thus considered as intracrines. In contrast, peptide or protein hormones generally act as endocrines, autocrines or paracrines by binding to their
..... Click the link for more information.
..... Click the link for more information.
1. Pineal gland 2. Pituitary gland 3. Thyroid gland 4. Thymus 5. Adrenal gland 6. Pancreas 7. Ovary 8. Testes]]
The endocrine system
..... Click the link for more information.
The endocrine system
..... Click the link for more information.
Testosterone is a steroid hormone from the androgen group. Testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid.
..... Click the link for more information.
..... Click the link for more information.
The testicle (from Latin testis, meaning "witness",[1] plural testes) or ballock is the male generative gland in animals. This article will concentrate on mammalian testicles unless otherwise noted.
..... Click the link for more information.
..... Click the link for more information.
Spermatogenesis is the process by which male spermatogonia develop into mature spermatozoa. Spermatozoa are the mature male gametes, in many sexually reproducing organisms. Thus, spermatogenesis is the male version of gametogenesis.
..... Click the link for more information.
..... Click the link for more information.
Seminiferous tubules are located in the testicles, and are the specific location of meiosis, and the subsequent creation of gametes, namely spermatozoa.
The epithelium of the tubule consists of sustentacular or Sertoli cells, which are tall, columnar type cells that line
..... Click the link for more information.
The epithelium of the tubule consists of sustentacular or Sertoli cells, which are tall, columnar type cells that line
..... Click the link for more information.
1. Pineal gland 2. Pituitary gland 3. Thyroid gland 4. Thymus 5. Adrenal gland 6. Pancreas 7. Ovary 8. Testes]]
The endocrine system
..... Click the link for more information.
The endocrine system
..... Click the link for more information.
Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed
..... Click the link for more information.
..... Click the link for more information.
eMedicine is an online clinical medical knowledge base that was founded in 1996 by Scott Plantz and Richard Lavely, two medical doctors. It was sold to WebMD in January 2006.
..... Click the link for more information.
..... Click the link for more information.
Dorland's is the brand name of several different medical dictionaries and ancillary products, chiefly Dorland's Illustrated Medical Dictionary (currently in its 31st edition) and Dorland's Pocket Medical Dictionary (currently in its 27th edition).
..... Click the link for more information.
..... Click the link for more information.
GPnotebook is a British medical database for general practitioners (GPs).[1] It is an online encyclopaedia of medicine that provides an immediate reference resource for clinicians worldwide. The database consists of over 30,000 pages of information.
..... Click the link for more information.
..... Click the link for more information.
Cell physiology (or cellular electrophysiology) is the biological study of the cell's mechanism and interaction in its environment.
In the context of human physiology, cell physiology is often the term used to describe the physiology of membrane transport, neuron
..... Click the link for more information.
In the context of human physiology, cell physiology is often the term used to describe the physiology of membrane transport, neuron
..... Click the link for more information.
Cell signaling is part of a complex system of communication that governs basic cellular activities and coordinates cell actions. The ability of cells to perceive and correctly respond to their microenvironment is the basis of development, tissue repair, and immunity as well as
..... Click the link for more information.
..... Click the link for more information.
ligand (latin ligare = to bind) is a molecule that is able to bind to and form a complex with a biomolecule to serve a biological purpose. In a narrower sense, it is an effector molecule binding to a site on a target protein, by intermolecular forces such as ionic bonds,
..... Click the link for more information.
..... Click the link for more information.
Cell signaling pathways interact with one another to form networks in natural systems.
Such networks are highly complex in their organization and can exhibit a number of emergent properties including bistability and ultrasensitivity.
..... Click the link for more information.
Such networks are highly complex in their organization and can exhibit a number of emergent properties including bistability and ultrasensitivity.
..... Click the link for more information.
In biology, signal transduction refers to any process by which a cell converts one kind of signal or stimulus into another, most often involving ordered sequences of biochemical reactions inside the cell, that are carried out by enzymes, activated by second messengers resulting in
..... Click the link for more information.
..... Click the link for more information.
In cell physiology, a secondary messenger system (also known as a second messenger system) is a method of cellular signalling where the signalling molecule does not enter the cell, but rather utilizes a cascade of events that transduces the signal into a cellular change.
..... Click the link for more information.
..... Click the link for more information.
This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.
Herod_Archelaus
