An update on the extraneuronal monoamine transporter (EMT): Characteristics, distribution and regulation

• Type: Another Publication in an International Scientific Journal
• Date: 2003

Authors

Martel, F (Author) FMUP; Azevedo, I (Author) Other

Journal

Title: Current Drug Metabolism

Vol. 4

Pages: 313-318

ISSN: 1389-2002

Publisher: Bentham

Indexing

ISI Web of Knowledge - 23 Citations

Scopus - 24 Citations

Other information

Authenticus ID: P-000-FMR

DOI: 10.2174/1389200033489433

Abstract (EN): Biological membranes prevent transmembrane diffusion in the majority of organic molecules that bear net charges at physiological pH. Consequently, these compounds must use more or less specific membrane-bound transport systems to be imported into or exported from cells or organisms. The extraneuronal monoamine transporter (EMT) is a transmembranar transport system involved in the transfer of monoamine compounds across cell membranes. It was identified more than 30 years ago [1], its functional characteristics being thereafter described [review by 2]. The recent cloning of this transporter in mail and rat reopened investigation and interest in this entity. EMT is a Na+ and Cl--independent, potential-dependent carrier, known to have a broad tissue distribution (ea. myocardium, vascular and non-vascular smooth muscle cells, glandular cells, placenta and CNS glial cells). According to its transport function and primary structure, EMT is included in the amphiphilic Solute facilitator (ASF) family of transporters. Physiological Substrates for EMT include the monoamines serotonin, dopamine, noradrenaline. adrenaline and histamine. Moreover, several xenobiotics including the neurotoxin 1-methyl-4-phenylpyridinium, clonidine, cimetidine and the K+-channel blocker tetraethylammonium interact with this transporter. The aim of this work is to review knowledge concerning EMT, making all Update on its functional characteristics. physiological importance and regulation. A special emphasis will be given to very recent investigations concerning regulation of EMT by intracellular second messenger systems and the interaction of modulators of P-glycoprotein, the product of the multidrug resistance gene MDR1, with EMT.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6