Small effect of dopamine release and no effect of dopamine depletion on [18F]fallypride binding in healthy humans

@article{Cropley2008SmallEO,
  title={Small effect of dopamine release and no effect of dopamine depletion on [18F]fallypride binding in healthy humans},
  author={Vanessa L. Cropley and Robert B. Innis and Pradeep J. Nathan and Amira K. Brown and Janet Sangare and Alicja Lerner and Yong Hoon Ryu and Kelly E. Sprague and Victor W. Pike and Masahiro Fujita},
  journal={Synapse},
  year={2008},
  volume={62}
}
Molecular imaging has been used to estimate both drug‐induced and tonic dopamine release in the striatum and most recently extrastriatal areas of healthy humans. However, to date, studies of drug‐induced and tonic dopamine release have not been performed in the same subjects. This study performed positron emission tomography (PET) with [18F]fallypride in healthy subjects to assess (1) the reproducibility of [18F]fallypride and (2) both D‐amphetamine‐induced and α‐methyl‐p‐tyrosine (AMPT… 

Striatal and extrastriatal dopamine release measured with PET and [18F] fallypride

TLDR
It is concluded that [18F] fallypride is a suitable ligand for measuring amphetamine effect in striatum and limbic regions, but it is not suitable for measuring the effect in cortical regions and may not provide the most powerful way to measure the effectIn striatum.

[18F]fallypride PET measurement of striatal and extrastriatal dopamine D2/3 receptor availability in recently abstinent alcoholics

TLDR
Receptor availability was unaltered by acute withdrawal, but increased in the subgroup of patients with long‐term follow‐up, suggesting reversibility of receptor changes.

Failure to detect amphetamine‐induced dopamine release in the cortex with [11C]FLB 457 positron emission tomography (PET): Methodological considerations

TLDR
Data is presented from a cohort of twelve healthy controls in whom an oral amphetamine challenge did not lead to a significant reduction in [11C]FLB 457 BPND (i.e., binding potential relative to non‐displaceable uptake), highlighting the methodological challenges that continue to plague the field with respect to imaging dopamine release in the cortex.

No effect of dopamine depletion on the binding of the high‐affinity D2/3 radiotracer [11C]FLB 457 in the human cortex

TLDR
The findings support the use of [11C]FLB 457 to measure changes in cortical synaptic DA induced by amphetamine and examine the effects of DA depletion with α‐methyl‐para‐tyrosine (α‐MPT) on [ 11C] FLB 457 binding in the cortex.

Reproducibility of Post-Amphetamine [11C]FLB 457 Binding to Cortical D2/3 Receptors

TLDR
Reconcibility and reliability of [11C]FLB 457 binding potential relative to non-displaceable uptake (BPND) following an acute amphetamine challenge are reported on to demonstrate that the post-amphetamine [ 11C] FLB 457 BPND is reproducible.

Characterization of extrastriatal D2 in vivo specific binding of [18F](N‐methyl)benperidol using PET

TLDR
These findings indicate that PET with [18F]NMB measures specific binding in extrastriatal regions, making it a viable radioligand to study extrastiatal D2R levels in healthy and diseased states.

Imaging dopamine transmission in the frontal cortex: a simultaneous microdialysis and [11C]FLB 457 PET study

TLDR
The magnitude of dialysate dopamine release is correlated with the magnitude of the reduction in [11C]FLB 457 BPND in the frontal cortex, which should allow for characterization of prefrontal cortical dopamine release in neuropsychiatric disorders such as schizophrenia and addiction.

The effects of d-amphetamine on extrastriatal dopamine D2/D3 receptors: a randomized, double-blind, placebo-controlled PET study with [11C]FLB 457 in healthy subjects

TLDR
This placebo-controlled study showed that d-amphetamine does not induce marked changes in measures of extrastriatal dopamine D2/D3 receptor binding, indicating that [11C]FLB 457 PET is not a useful method for measuring extrastiatal dopamine release in humans.

Imaging dopamine transmission in the frontal cortex: a simultaneous microdiaysis and [11C]FLB 457 PET study

TLDR
The magnitude of dialysate DA release is correlated with the magnitude of the reduction in [11C]FLB 457 BPND in the frontal cortex, which should allow for characterization of prefrontal cortical DA release in neuropsychiatric disorders such as schizophrenia and addiction.

Estimating the effect of endogenous dopamine on baseline [11C]‐(+)‐PHNO binding in the human brain

TLDR
The agonist radiotracer [11C]‐(+)‐PHNO can detect the impact of endogenous DA levels at D2/3R in the living human brain from a single baseline scan, and may be more sensitive to this impact than other commonly employed radiot Racers.
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