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Histamine Agonists
A histamine agonist is a drug which causes increased activity at one or more of the four histamine receptor subtypes. H2: Betazole and Impromidine are examples of agonists used in diagnostics to increase histamine. H3: Betahistine is a weak Histamine1 agonist and a very strong Histamine3 antagonist (paradoxically histamine increasing). See also * Histamine antagonist Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides re ... External links * * {{pharmacology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histamine Receptor
The histamine receptors are a class of G protein–coupled receptors which bind histamine as their primary endogenous ligand. There are four known histamine receptors: * H1 receptor * H2 receptor * H3 receptor * H4 receptor Comparison There are several splice variants of H3 present in various species. Though all of the receptors are 7-transmembrane g protein coupled receptors, H1 and H2 are quite different from H3 and H4 in their activities. H1 causes an increase in PIP2 hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolys ..., H2 stimulates gastric acid secretion, and H3 mediates feedback inhibition of histamine. References External links *Holger Stark: Histamine Receptors, BIOTREND Reviews No. 01, November 2007 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betazole
Betazole (also known as ametazole) is a histamine H2 receptor agonist. Betazole hydrochloride is known as gastramine and histalog. It has been used as a gastric stimulant to test for maximal production of gastric secretion activity. The test can be used in diagnosis of diseases such as Zollinger-Ellison syndrome where there is excess acid production, in this case driven by over production of gastrin. The volume of acid secretion is measured following administration of betazole, diagnosis being secretion greater than 60% of the maximal acid secretion following betazole stimulation. This procedure can lead to complications and should be avoided in subjects with coronary artery disease. It is also used in diagnosis of gastritis in association with a test for secretin activity. Betazole is used as a stimulant in preference to histamine because of its specificity for the H2 receptor and its advantage of not generating the undesirable side effects that histamine would induce. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impromidine
Impromidine (INN) is a highly potent and specific histamine H2 receptor agonist. It has been used diagnostically as a gastric secretion indicator. See also * Histamine agonists A histamine agonist is a drug which causes increased activity at one or more of the four histamine receptor subtypes. H2: Betazole and Impromidine are examples of agonists used in diagnostics to increase histamine. H3: Betahistine is a weak Hist ... References Imidazoles Guanidines Thioethers {{gastrointestinal-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betahistine
Betahistine, sold under the brand name Serc among others, is an anti-vertigo medication. It is commonly prescribed for balance disorders or to alleviate vertigo symptoms. It was first registered in Europe in 1970 for the treatment of Ménière's disease but current evidence does not support its efficacy in treating it. Medical uses Betahistine was once believed to have some positive effects in the treatment of Ménière's disease and vertigo but more recent evidence casts doubt over its efficacy. There have been studies of the use of betahistine which showed a reduction in symptoms of vertigo and to a lesser extent, tinnitus, in subjects, but conclusive evidence is lacking at present. Oral betahistine has been approved for the treatment of Ménière’s disease and vestibular vertigo in more than 80 countries worldwide, and has been reportedly prescribed more than 130 million patients. However, betahistine has not been approved for marketing in the United States for the past ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histamine Antagonist
Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides relief from nasal congestion, sneezing, or hives caused by pollen, dust mites, or animal allergy with few side effects. Antihistamines are usually for short-term treatment. Chronic allergies increase the risk of health problems which antihistamines might not treat, including asthma, sinusitis, and lower respiratory tract infection. Consultation of a medical professional is recommended for those who intend to take antihistamines for longer-term use. Although people typically use the word "antihistamine" to describe drugs for treating allergies, doctors and scientists use the term to describe a class of drug that opposes the activity of histamine receptors in the body. In this sense of the word, antihistamines are subclassified according to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |