Target type: biologicalprocess
The chemical reactions and pathways resulting in the breakdown of any of a group of physiologically important biogenic amines that possess a catechol (3,4-dihydroxyphenyl) nucleus and are derivatives of 3,4-dihydroxyphenylethylamine. [GOC:jl, ISBN:0198506732]
Catecholamine catabolic process is a fundamental biochemical pathway that governs the breakdown and inactivation of catecholamines, a group of neurotransmitters and hormones including dopamine, norepinephrine, and epinephrine. This process is crucial for maintaining normal physiological function, particularly in the nervous system and cardiovascular system. The catabolism of catecholamines primarily occurs through two major pathways:
1. **O-methylation:** This pathway involves the enzymatic conversion of catecholamines into their corresponding methoxy derivatives, catalyzed by catechol-O-methyltransferase (COMT). For example, dopamine is converted to 3-methoxytyramine (also known as metaraminol), norepinephrine is converted to normetanephrine, and epinephrine is converted to metanephrine.
2. **Deamination:** The second pathway involves the removal of the amino group from catecholamines, catalyzed by monoamine oxidase (MAO). MAO exists in two major isoforms: MAO-A and MAO-B. MAO-A preferentially deaminates norepinephrine and serotonin, while MAO-B primarily deaminates dopamine. This step produces aldehyde intermediates, which are further metabolized by aldehyde dehydrogenase into inactive metabolites. For instance, dopamine is deaminated to 3,4-dihydroxyphenylacetaldehyde, which is then converted to homovanillic acid (HVA).
These two pathways can occur sequentially, with O-methylation often preceding deamination. However, the relative contribution of each pathway varies depending on the specific catecholamine and the tissue.
The breakdown products of catecholamine catabolism are excreted in urine and provide valuable clinical biomarkers for monitoring catecholamine metabolism and detecting potential disorders, such as pheochromocytoma (a tumor that secretes catecholamines).
In summary, catecholamine catabolic process is a complex and vital biochemical pathway that controls the levels of catecholamines in the body. It involves a series of enzymatic reactions that convert active catecholamines into inactive metabolites, ensuring proper neurotransmission and physiological function.'
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Protein | Definition | Taxonomy |
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Catechol O-methyltransferase | A catechol O-methyltransferase that is encoded in the genome of human. [PRO:DNx, UniProtKB:P21964] | Homo sapiens (human) |
Compound | Definition | Classes | Roles |
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oxyquinoline | Oxyquinoline: An antiseptic with mild fungistatic, bacteriostatic, anthelmintic, and amebicidal action. It is also used as a reagent and metal chelator, as a carrier for radio-indium for diagnostic purposes, and its halogenated derivatives are used in addition as topical anti-infective agents and oral antiamebics. quinolin-8-ol : A monohydroxyquinoline that is quinoline substituted by a hydroxy group at position 8. Its fungicidal properties are used for the control of grey mould on vines and tomatoes. | monohydroxyquinoline | antibacterial agent; antifungal agrochemical; antiseptic drug; iron chelator |
verapamil | 2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl](methyl)amino}-2-(propan-2-yl)pentanenitrile : A tertiary amino compound that is 3,4-dimethoxyphenylethylamine in which the hydrogens attached to the nitrogen are replaced by a methyl group and a 4-cyano-4-(3,4-dimethoxyphenyl)-5-methylhexyl group. verapamil : A racemate comprising equimolar amounts of dexverapamil and (S)-verapamil. An L-type calcium channel blocker of the phenylalkylamine class, it is used (particularly as the hydrochloride salt) in the treatment of hypertension, angina pectoris and cardiac arrhythmia, and as a preventive medication for migraine. Verapamil: A calcium channel blocker that is a class IV anti-arrhythmia agent. | aromatic ether; nitrile; polyether; tertiary amino compound | |
8-hydroxyquinoline-5-sulfonic acid | 8-hydroxyquinoline-5-sulfonic acid: RN given refers to parent cpd | ||
5'-methylthioadenosine | 5'-methylthioadenosine: structure 5'-S-methyl-5'-thioadenosine : Adenosine with the hydroxy group at C-5' substituted with a methylthio (methylsulfanyl) group. | thioadenosine | algal metabolite; Escherichia coli metabolite; human metabolite; mouse metabolite; Saccharomyces cerevisiae metabolite |
sitagliptin | sitagliptin : A triazolopyrazine that exhibits hypoglycemic activity. | triazolopyrazine; trifluorobenzene | EC 3.4.14.5 (dipeptidyl-peptidase IV) inhibitor; environmental contaminant; hypoglycemic agent; serine proteinase inhibitor; xenobiotic |
tolcapone | tolcapone : Benzophenone substituted on one of the phenyl rings at C-3 and C-4 by hydroxy groups and at C-5 by a nitro group, and on the other phenyl ring by a methyl group at C-4. It is an inhibitor of catechol O-methyltransferase. Tolcapone: A benzophenone and nitrophenol compound that acts as an inhibitor of CATECHOL O-METHYLTRANSFERASE, an enzyme involved in the metabolism of DOPAMINE and LEVODOPA. It is used in the treatment of PARKINSON DISEASE in patients for whom levodopa is ineffective or contraindicated. | 2-nitrophenols; benzophenones; catechols | antiparkinson drug; EC 2.1.1.6 (catechol O-methyltransferase) inhibitor |
entacapone | entacapone : A monocarboxylic acid amide that is N,N-diethylprop-2-enamide in which the hydrogen at position 2 is substituted by a cyano group and the hydrogen at the 3E position is substituted by a 3,4-dihydroxy-5-nitrophenyl group. entacapone: structure given in first source | 2-nitrophenols; catechols; monocarboxylic acid amide; nitrile | antidyskinesia agent; antiparkinson drug; central nervous system drug; EC 2.1.1.6 (catechol O-methyltransferase) inhibitor |
opicapone | opicapone: structure in first source | oxadiazole; ring assembly |