Conducting states of a mammalian serotonin transporter

doi:10.1016/0896-6273(94)90337-9

Neuron

Volume 12, Issue 4, April 1994, Pages 845-859

https://doi.org/10.1016/0896-6273(94)90337-9 Get rights and content

Abstract

We have studied permeation at a cloned rat 5-HT transporter expressed in Xenopus oocytes. [³H)5-HT uptake and [¹²⁵I]RTI-55 binding yield a turnover rate of ∼1/s that does not depend on membrane potential. However, in voltage-clamp experiments, three distinct currents result from 5-HT transporter expression. First, a steady-state, voltage-dependent transport-associated current is induced by 5-HT application. Second, a transient inward current is activated by voltage jumps to high negative potentials in the absence of 5-HT and is blocked by 5-HT itself. Third, a small leakage current is observed in the absence of 5-HT. All the observed currents are blocked by inhibitors of 5-HT uptake but are differentially affected by Na⁺, Li⁺, K⁺, Ba²⁺, Cs⁺, Cl⁻, and amiloride. The conducting states of the 5-HT transporter may reflect the existence of a permeation pathway similar to that of ionic channels.

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Neuron

ArticleConducting states of a mammalian serotonin transporter

Abstract

Neuron

Biochim. Biophys. Acta

J. Biol. Chem.

Biochim. Biophys. Acta

Neuron

J. Biol. Chem.

J. Biol. Chem.

Meth. Neurosci.

Biochem. Pharmacol.

J. Biol. Chem.

Biochim. Biophys. Acta

J. Biol. Chem.

J. Biol. Chem.

Biophys. J.

J. Biol. Chem.

Neuropharmacology

Neurotransmitter transporters-recent progress

Annu. Rev. Neurosci.

Electrogenic glutamate uptake in glial cells is activated by intracellular potassium

Nature

Cloning and expression of a functional serotonin transporter from rat brain

Nature

High affinity binding of [125]RTI-55 to dopamine and serotonin transporters in rat brain

Synapse

Control of Torpedo acetylcholine receptor biosynthesis in Xenopus oocytes

A Drosophila serotonin transporter: cloning, expression, and electrophysiological characterization

Extracellular access to the Na,K pump: pathway similar to ion channel

Science

Article
Conducting states of a mammalian serotonin transporter

High affinity binding of [¹²⁵]RTI-55 to dopamine and serotonin transporters in rat brain