Gene SLC22A3
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Also known as
Solute Carrier Family 22 Member 3, OCT3, EMTOverview
SLC22A3 (Solute Carrier Family 22 Member 3) encodes organic cation transporter 3 (OCT3), a polyspecific transporter protein that mediates the uptake and clearance of various endogenous compounds and xenobiotics. OCT3 is widely expressed throughout the body, including in the brain, heart, liver, kidney, and placenta, where it transports monoamine neurotransmitters (dopamine, norepinephrine, serotonin, and histamine), as well as various drugs and toxins. In the brain, OCT3 plays an important role in terminating neurotransmitter signaling by removing excess monoamines from the extracellular space, complementing the more specific reuptake transporters.Genetic variants in SLC22A3 have been associated with several phenotypes related to its diverse substrate profile. Some polymorphisms may influence individual responses to drugs that are OCT3 substrates, including certain antidepressants, antihistamines, and chemotherapy agents. Variants have also been linked to cardiovascular disease risk, potentially through effects on catecholamine clearance and blood pressure regulation. Because OCT3 plays a role in histamine transport, SLC22A3 genetic variation may influence histamine-related conditions and responses to antihistamine medications. Understanding SLC22A3 genetic variation could help personalize medication selection and dosing for drugs that depend on this transporter for their pharmacokinetics.