Biomaterial Database

Monoamine oxidase and catechol-O-methyltransferase activity in hamster and rat insulinomas. 1979

J M Feldman, and D S Reintgen, and H F Seigler

Hamster and rat insulinomas were assayed for norepinephrine, dopamine and serotonin concentration and for monoamine oxidase and catechol-o-ethyltransferase (COMT) activity. The concentration of norepinephrine (mean 0.55 mumol/kg, range less than 0.20 to 2.64 mumol/kg) and serotonin (mean 5.22 mucol/kg, rang less than 0.6 to 26.5 mumol/kg) in hamster insulinomas were comparable to previously reported concentrations. Dopamine conentration (mean 0.34 mumol/kg, range less than 0.20 to 0.95 mumol/kg) was only 2 to 2.5% of that reported previously. Monoamine oxidase activity of the hamster and rat insulinomas were comparable to those of normal hamster islets. In contrast, the COMT activity of both insulinomas was much greater than the COMT activity of normal pancreatic islets of both species and was greater than in several other tissues and tumours. The tumour COMT, which was predominantly in the cytosol, was Mg2+ dependent and had a comparable sensitivity to inhibition by tropolone as purified beef-liver COMT. Hamster insulinoma monoamine oxidase was more sensitive than rat insulinoma monoamine oxidase to inhibition by tranylcypromine and deprenyl, while rat insulinoma monoamine oxidase was more sensitive to inhibition by clorgyline and was more heat labile.

UI	MeSH Term	Description	Entries
D007516	Adenoma, Islet Cell	A benign tumor of the pancreatic ISLET CELLS. Usually it involves the INSULIN-producing PANCREATIC BETA CELLS, as in INSULINOMA, resulting in HYPERINSULINISM.	Islet Cell Tumor,Islet of Langerhans Tumor,Nesidioblastoma,Pancreatic Islet Cell Tumors,Island Cell Tumor,Adenomas, Islet Cell,Island Cell Tumors,Islet Cell Adenoma,Islet Cell Adenomas,Islet Cell Tumors,Langerhans Tumor Islet,Nesidioblastomas,Tumor Islet, Langerhans,Tumor, Island Cell,Tumor, Islet Cell,Tumors, Island Cell,Tumors, Islet Cell
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008995	Monoamine Oxidase	An enzyme that catalyzes the oxidative deamination of naturally occurring monoamines. It is a flavin-containing enzyme that is localized in mitochondrial membranes, whether in nerve terminals, the liver, or other organs. Monoamine oxidase is important in regulating the metabolic degradation of catecholamines and serotonin in neural or target tissues. Hepatic monoamine oxidase has a crucial defensive role in inactivating circulating monoamines or those, such as tyramine, that originate in the gut and are absorbed into the portal circulation. (From Goodman and Gilman's, The Pharmacological Basis of Therapeutics, 8th ed, p415) EC 1.4.3.4.	Amine Oxidase (Flavin-Containing),MAO,MAO-A,MAO-B,Monoamine Oxidase A,Monoamine Oxidase B,Type A Monoamine Oxidase,Type B Monoamine Oxidase,Tyramine Oxidase,MAO A,MAO B,Oxidase, Monoamine,Oxidase, Tyramine
D009374	Neoplasms, Experimental	Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.	Experimental Neoplasms,Experimental Neoplasm,Neoplasm, Experimental
D009638	Norepinephrine	Precursor of epinephrine that is secreted by the ADRENAL MEDULLA and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the LOCUS CERULEUS. It is also found in plants and is used pharmacologically as a sympathomimetic.	Levarterenol,Levonorepinephrine,Noradrenaline,Arterenol,Levonor,Levophed,Levophed Bitartrate,Noradrenaline Bitartrate,Noradrénaline tartrate renaudin,Norepinephrin d-Tartrate (1:1),Norepinephrine Bitartrate,Norepinephrine Hydrochloride,Norepinephrine Hydrochloride, (+)-Isomer,Norepinephrine Hydrochloride, (+,-)-Isomer,Norepinephrine d-Tartrate (1:1),Norepinephrine l-Tartrate (1:1),Norepinephrine l-Tartrate (1:1), (+,-)-Isomer,Norepinephrine l-Tartrate (1:1), Monohydrate,Norepinephrine l-Tartrate (1:1), Monohydrate, (+)-Isomer,Norepinephrine l-Tartrate (1:2),Norepinephrine l-Tartrate, (+)-Isomer,Norepinephrine, (+)-Isomer,Norepinephrine, (+,-)-Isomer
D002394	Catechol O-Methyltransferase	Enzyme that catalyzes the movement of a methyl group from S-adenosylmethionone to a catechol or a catecholamine.	Catechol Methyltransferase,Catechol-O-Methyltransferase,Catechol O Methyltransferase,Methyltransferase, Catechol,O-Methyltransferase, Catechol
D003010	Clorgyline	An antidepressive agent and monoamine oxidase inhibitor related to PARGYLINE.	Clorgilin,Chlorgyline,Clorgiline
D004298	Dopamine	One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.	Hydroxytyramine,3,4-Dihydroxyphenethylamine,4-(2-Aminoethyl)-1,2-benzenediol,Dopamine Hydrochloride,Intropin,3,4 Dihydroxyphenethylamine,Hydrochloride, Dopamine
D006224	Cricetinae	A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.	Cricetus,Hamsters,Hamster
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia