Fluorescent reporters of monoamine transporter distribution and function.

Serotonin is a monoamine serving as a chemical messenger in diverse brain regions, as well as in blood and various other organs. We synthesized six ethylamine functionalized fluorophores as fluorescent probes for serotonin. The one with best spectral properties and aqueous solubility, 6-amino-2-(2-aminoethyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione, was studied in detail both in vivo and in vitro.

Fluorescent neuroactive probes based on stilbazolium dyes.

A set of spectrally diverse stilbazolium dyes was identified in an uptake assay using cultured brainstem and cerebellum cells isolated from e19 chicks. Pretreatment of cells with indatraline, a monoamine reuptake inhibitor, allowed identification of dyes that may interact with monoamine transporters. Two structurally related, yet spectrally segregated, probes, (E)-1-methyl-4-[2-(2-naphthalenyl)ethenyl]-pyridinium iodide (NEP+, 3A) and (E)-4-[2-(6-hydroxy-2-naphthalenyl)ethenyl]-1-methyl-pyridinium iodide (HNEP+, 4A), were selected and further investigated using HEK-293 cells selectively expressing dopamine, norepinephrine or serotonin transporters.

Fluorescent mimics of 5-hydroxytryptamine based on N-alkylated derivatives of 6-hydroxycarbostyril.

Fluorescent probes based on a 6-hydroxycarbostyril core accumulate inside neurons and astroglia in the absence of a serotonin uptake inhibitor.