Publications by authors named "Penny G Threlkeld"

A series of 1-aryloxy-3-piperidinylpropan-2-ols possessing potent dual 5-HT1A receptor antagonism and serotonin reuptake inhibition was discovered. 1-(1H-Indol-4-yloxy)-3-(4-benzo[b]thiophen-2-ylpiperidinyl)propan-2-ols exhibited selective and high affinities at the 5-HT1A receptor and serotonin reuptake site in vitro. In vivo evaluation of this series of compounds demonstrated elevated extracellular serotonin levels from the basal and quick recovery of neuron firing that was presumably suppressed by the initial acute activation of 5-HT1A somatodendritic autoreceptors.

View Article and Find Full Text PDF

A series of 1-(1H-indol-4-yloxy)-3-(4-arylpiperidinyl)propan-2-ols possessing potent dual 5-HT(1A) receptor antagonism and serotonin reuptake inhibition was discovered. The fused aryl ring moiety contributed to the robust dual activities irrespective of the regiochemistry associated with its connectivity to the piperidine central ring.

View Article and Find Full Text PDF

A series of 1-aryloxy-3-piperidinylpropan-2-ols possessing potent dual 5-HT(1A) receptor antagonism and serotonin reuptake inhibition was discovered. Modification of potential metabolic sites of 1-(1H-indol-4-yloxy)-3-(4-benzo[b]thiophen-2-ylpiperidinyl)propan-2-ols further improved the in vitro binding affinities and functional antagonism.

View Article and Find Full Text PDF
Article Synopsis
  • The study examines the effectiveness of four dual transporter inhibitors—chlorimipramine, duloxetine, milnacipran, and venlafaxine—in blocking serotonin (5-HT) and norepinephrine (NE) transporters for potential antidepressant use.
  • While all compounds blocked both transporters to some extent, chlorimipramine and duloxetine showed higher potency, significantly increasing extracellular levels of monoamines in rat brain.
  • In contrast, milnacipran had a weaker effect on NE levels, and venlafaxine predominantly affected 5-HT at lower doses, suggesting varying levels of efficacy among the inhibitors when targeting both transporters.
View Article and Find Full Text PDF

Potent 5-HT1A/SSRIs at low nanomolar and subnanomolar concentrations were identified in a series of 1-(1H-indol-4-yloxy)-3-(4-benzo[b]thiophen-2-ylpiperidinyl)propan-2-ols. Incorporation of an alpha-Me group in the piperidine ring with its specific stereochemistry enhanced binding affinity at the 5-HT reuptake site and in vitro 5-HT(1A) antagonist functional activity.

View Article and Find Full Text PDF

A series of 1-aryloxy-3-piperidinylpropan-2-ols possessing potent dual 5-HT(1A) receptor antagonism and serotonin reuptake inhibition was discovered. 1-(1H-Indol-4-yloxy)-3-(4-benzo[b]thiophen-2-ylpiperidinyl)propan-2-ols exhibited selective and high affinity at the 5-HT(1A) receptor and serotonin reuptake inhibition at nanomolar concentrations for dual activities.

View Article and Find Full Text PDF

The selective serotonin reuptake inhibitor fluoxetine consists of equal amounts of R and S stereoisomers. In this study, we investigated the pharmacologic properties of the stereoisomers using transporter and receptor binding assays and in vivo microdialysis in freely moving rats. Binding to the transporter confirmed selectivity of R- and S-fluoxetine for the 5-HT transporter versus the dopamine (DA) and norepinephrine (NE) human transporters.

View Article and Find Full Text PDF

The selective norepinephrine (NE) transporter inhibitor atomoxetine (formerly called tomoxetine or LY139603) has been shown to alleviate symptoms in Attention Deficit/Hyperactivity Disorder (ADHD). We investigated the mechanism of action of atomoxetine in ADHD by evaluating the interaction of atomoxetine with monoamine transporters, the effects on extracellular levels of monoamines, and the expression of the neuronal activity marker Fos in brain regions. Atomoxetine inhibited binding of radioligands to clonal cell lines transfected with human NE, serotonin (5-HT) and dopamine (DA) transporters with dissociation constants (K(i)) values of 5, 77 and 1451 nM, respectively, demonstrating selectivity for NE transporters.

View Article and Find Full Text PDF