HORMON LOKAL(Dr. I Dewa Ayu Susilawati, drg. M. Kes)TujuanSetelah mempelajari bab ini, anda diharapkan mampu:1. Menjelaskan pengertian hormon lokal2. Menjelaskan jenis-jenis hormon lokal3. Menjelaskan mekanisme kerja hormon lokal

Target sel hormon lokal berada di jaringan atau sel di sekitar sekretori sel* Hormone parakrin : target sel di sekitar sel sekretori* Hormon autokrin disekresi suatu sel dan aksinya mempengaruhi sel itu sendiri.* Sedangkan juxtakrin adalah jenis komunikasi interselular yang melibatkan sel-sel yang letaknya berdempetan.

Beberapa jenis hormon lokalAutokoids: bradikinin, histamin, prostaglandin(berperan pada reaksi inflamatori)NeurotransmiterSitokin

Bradykinin is a peptide that causes blood vessels to enlarge (dilate), and therefore causes blood pressure to lower. A class of drugs called ACE inhibitors, which are used to lower blood pressure, increase bradykinin (by inhibiting its degradation) further lowering blood pressure. Bradykinin works on blood vessels through the release of prostacyclin, nitric oxide, and Endothelium-Derived Hyperpolarizing Factor.

Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter.[1] Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by basophils and by mast cells found in nearby connective tissues. Histamine increases the permeability of the capillaries to white blood cells and other proteins, in order to allow them to engage foreign invaders in the infected tissues.[2] It is found in virtually all animal body cells

Prostaglandin is any member of a group of lipid compounds that are derived enzymatically from fatty acids and have important functions in the animal body. Every prostaglandin contains 20 carbon atoms, including a 5-carbon ring.They are mediators and have a variety of strong physiological effects, such as regulating the contraction and relaxation of smooth muscle tissue.[1] Prostaglandins are autocrine or paracrine, which are locally acting messenger molecules.

Neurotransmitters: chemical released by neurons to stimulate neighbouring neurons, allowing impulses to be passed from one cell to the next throughout the nervous system. A nerve impulse arriving at the axon terminal of one neuron stimulates release of a neurotransmitter, which crosses the microscopic gap (see synapse) in milliseconds to the adjoining neuron's dendrite. Many chemicals are believed to act as neurotransmitters. The few that have been identified include acetylcholine, dopamine, and serotonin.

Cytokines (Greek cyto-, cell; and -kinos, movement) are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication. Cytokines can be classified as proteins, peptides, or glycoproteins; the term "cytokine" encompasses a large and diverse family of regulators produced throughout the body by cells of diverse embryological origin.

- limfokin diproduksi limfosit- interleukin komunikasi antar lekositsitokin diproduksi oleh berbagai selContoh sitokin:- Interleukin- TNF alfa- Interferon gama

Interleukins are a group of cytokines (secreted proteins/signaling molecules) that were first seen to be expressed by white blood cells (leukocytes). The term interleukin derives from (inter-) "as a means of communication", and (-leukin) "deriving from the fact that many of these proteins are produced by leukocytes and act on leukocytes". The name is something of a relic though (the term was coined by Dr. Paetkau, University of Victoria); it has since been found that interleukins are produced by a wide variety of body cells. The function of the immune system depends in a large part on interleukins, and rare deficiencies of a number of them have been described, all featuring autoimmune diseases or immune deficiency. The majority of interleukins are synthesized by helper CD4+ T lymphocytes, as well as through monocytes, macrophages, and endothelial cells. They promote the development and differentiation of T, B, and hematopoietic cells.

Tumor necrosis factor (TNF, cachexin or cachectin and formerly known as tumor necrosis factor-alpha) is a cytokine involved in systemic inflammation and is a member of a group of cytokines that stimulate the acute phase reaction.The primary role of TNF is in the regulation of immune cells. TNF is able to induce apoptotic cell death, to induce inflammation, and to inhibit tumorigenesis and viral replication. Dysregulation of TNF production has been implicated in a variety of human diseases, as well as cancer.

Interferon-gamma (IFN-) is a dimerized soluble cytokine that is the only member of the type II class of interferons.[2] This interferon was originally called macrophage-activating factor, a term now used to describe a larger family of proteins to which IFN- belongs.IFN-, or type II interferon, is a cytokine that is critical for innate and adaptive immunity against viral and intracellular bacterial infections and for tumor control. Aberrant IFN- expression is associated with a number of autoinflammatory and autoimmune diseases

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