Cyclothiazide (Anhydron, Acquirel, Doburil, Fluidil, Renazide, Tensodiural, Valmiran), sometimes abbreviated CTZ, is a benzothiadiazide (

thiazide Thiazide () refers to both a class of sulfur-containing organic molecules and a class of diuretics based on the chemical structure of benzothiadiazine. The thiazide drug class was discovered and developed at Merck and Co. in the 1950s. The fir ...

)

diuretic A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics in ...

and

antihypertensive Antihypertensives are a class of drugs that are used to treat hypertension (high blood pressure). Antihypertensive therapy seeks to prevent the complications of high blood pressure, such as stroke and myocardial infarction. Evidence suggests that ...

that was originally introduced in the United States in 1963 by

Eli Lilly Eli Lilly (July 8, 1838 – June 6, 1898) was an American soldier, pharmacist, chemist, and businessman who founded the Eli Lilly and Company pharmaceutical corporation. Lilly enlisted in the Union Army during the American Civil War and r ...

and was subsequently also marketed in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

and Japan. Related

drug A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via inhal ...

s include diazoxide,

hydrochlorothiazide Hydrochlorothiazide is a diuretic medication often used to treat high blood pressure and swelling due to fluid build-up. Other uses include treating diabetes insipidus and renal tubular acidosis and to decrease the risk of kidney stones in th ...

, and

chlorothiazide Chlorothiazide, sold under the brand name Diuril among others, is an organic compound used as a diuretic and as an antihypertensive. It is used both within the hospital setting or for personal use to manage excess fluid associated with congestive ...

. In 1993, it was discovered that cyclothiazide is a

positive allosteric modulator In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a receptor to change that receptor's response to stimulus. Some of them, like benzodiazepines, are drugs. The site that an allosteric modulator binds to ...

of the

AMPA α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, better known as AMPA, is a compound that is a specific agonist for the AMPA receptor, where it mimics the effects of the neurotransmitter glutamate. There are several types of glutamaterg ...

and

kainate receptor Kainate receptors, or kainic acid receptors (KARs), are ionotropic receptors that respond to the neurotransmitter glutamate. They were first identified as a distinct receptor type through their selective activation by the agonist kainate, a dr ...

s, capable of reducing or essentially eliminating rapid desensitization of the former receptor, and potentiating AMPA-mediated

glutamate Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can syn ...

currents by as much as 18-fold at the highest concentration tested (100

μM The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Uni ...

). Additionally, in 2003, cyclothiazide was also found to act as a GABA_A receptor

negative allosteric modulator In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a receptor to change that receptor's response to stimulus. Some of them, like benzodiazepines, are drugs. The site that an allosteric modulator binds t ...

, potently inhibiting GABA_A-mediated currents. In animals it is a powerful

convulsant A convulsant is a drug which induces convulsions and/or epileptic seizures, the opposite of an anticonvulsant. These drugs generally act as stimulants at low doses, but are not used for this purpose due to the risk of convulsions and consequent exci ...

, robustly enhancing

epileptiform Epilepsy is a group of non-communicable neurological disorders characterized by recurrent epileptic seizures. Epileptic seizures can vary from brief and nearly undetectable periods to long periods of vigorous shaking due to abnormal electrical ...

activity and inducing

seizure An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with l ...

s, but without producing any apparent neuronal death. Cyclothiazide has been found to act as a

non-competitive antagonist A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of rec ...

of the

mGluR1 The glutamate receptor, metabotropic 1, also known as GRM1, is a human gene which encodes the metabotropic glutamate receptor 1 (mGluR1) protein. Function L-glutamate is the major excitatory neurotransmitter in the central nervous system and ...

. It is selective for mGluR1 over other

metabotropic glutamate receptor The metabotropic glutamate receptors, or mGluRs, are a type of glutamate receptor that are active through an indirect metabotropic process. They are members of the group C family of G-protein-coupled receptors, or GPCRs. Like all glutamate re ...

Synthesis

References

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Pharmacodynamics Pharmacodynamics (PD) is the study of the biochemical and physiologic effects of drugs (especially pharmaceutical drugs). The effects can include those manifested within animals (including humans), microorganisms, or combinations of organisms ( ...

, titlestyle = background:#ccccff , list1 = {{GABAA receptor modulators {{Glutamate receptor modulators Diuretics Sulfonamides AMPA receptor positive allosteric modulators Kainate receptor agonists Benzothiadiazines Chloroarenes GABAA receptor negative allosteric modulators Carbonic anhydrase inhibitors Convulsants MGlu1 receptor antagonists Alkene derivatives

Synthesis

See also

References