SLC22A3
Encyclopedia
Solute carrier family 22 member 3 (SLC22A3) also known as the organic cation transporter 3 (OCT3) or extraneuronal monoamine transporter (EMT) is a protein
that in humans is encoded by the SLC22A3 gene
.
. Capacity for transport and affinity for these substrates may vary between rat and human isoforms however.
Transport activity of OCT3 is inhibited by recreational and pharmaceutical drugs, including MDMA, PCP, MK-801, amphetamine, methamphetamine and Cocaine. Transport is also inhibited by the chemical decynium-22 and physiological concentrations of corticosterone
and cortisol
. Ki values for decynium-22 and corticosterone inhibition of OCT3 transport are respectively 10 and 100 times lower than Ki values of OCT1 and OCT2.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the SLC22A3 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Distribution
OCT3 is widely distributed in brain tissue. It is not yet completely clear whether its location is primarily neuronal or glial. Areas of the brain in which it has been reported include: hippocampus, retrosplenial cortex, visual cortex, hypothalamus, amygdala, nucleus accumbens, thalamus, raphe nucleus, subiculum, superior and inferior colliculi, and islands of Calleja.Pharmacology
Organic cation transporter 3 is a polyspecific transporter whose transport is independent of sodium. Known substrates for transport include: histamine, serotonin, norepinephrine, dopamine and MPP+MPP+
MPP+ is a positively charged molecule with chemical formula C12H12N+. It is toxic and acts by interfering with oxidative phosphorylation in mitochondria, causing depletion of ATP and cell death...
. Capacity for transport and affinity for these substrates may vary between rat and human isoforms however.
Transport activity of OCT3 is inhibited by recreational and pharmaceutical drugs, including MDMA, PCP, MK-801, amphetamine, methamphetamine and Cocaine. Transport is also inhibited by the chemical decynium-22 and physiological concentrations of corticosterone
Corticosterone
Corticosterone is a 21-carbon steroid hormone of the corticosteroid type produced in the cortex of the adrenal glands.-Roles:In many species, including amphibians, reptiles, rodents and birds, corticosterone is a main glucocorticoid, involved in regulation of fuel, immune reactions, and stress...
and cortisol
Cortisol
Cortisol is a steroid hormone, more specifically a glucocorticoid, produced by the adrenal gland. It is released in response to stress and a low level of blood glucocorticoids. Its primary functions are to increase blood sugar through gluconeogenesis; suppress the immune system; and aid in fat,...
. Ki values for decynium-22 and corticosterone inhibition of OCT3 transport are respectively 10 and 100 times lower than Ki values of OCT1 and OCT2.