PET Neurochemical Imaging Modes

Abstract

Positron emission tomography (PET) has deep roots in neuroscience stemming from its first applications in brain tumor and brain metabolism imaging. Over the past few decades, PET emerged and continues to play a prominent role in the study of neurochemistry in the living human brain. Over time, neurochemical imaging with PET has been expanded to address a host of research questions related to among many others, protein density, drug occupancy and endogenous neurochemical release. Each of these imaging modes has distinct design and analysis considerations that are critical for enabling quantitative measurements. The number of considerations required for a neurochemical PET study can make it unapproachable. This seminar aims to orient those interested in neurochemical PET imaging to three of the common imaging modes and to provide some perspective on needs that exist for expansion of neurochemical PET imaging.

Kappa-opioid receptors, dynorphin, and cocaine addiction: a positron emission tomography study

“…Although the exact mechanism of this is unclear, recent PET imaging studies in rodents show that [ 11 C]GR103545 binding is reduced by the administration of KOR agonists (salvinorin and U-50488), whereas kappa receptor antagonist radiotracers were not affected [48,49]. Previous PET studies have imaged changes in endogenous neurotransmitters, such as dopamine or endorphin, using a dopamine D 2 or mu receptor radiotracers, indicating that a change in radiotracer binding can be used to indirectly measure increases in neurotransmitter levels [50,51]. In this study, the mechanism behind the decrease in [ 11 C]GR103545 V T has not been identified.…”

Hydrofluoromethylation of alkenes with fluoroiodomethane and beyond

“…[46][47][48] Compounds labelled with the radioisotope F-18 are important for applications in Positron Emission Tomography (PET). [49][50][51][52][53] The synthesis of [ 18 F]CH 2 FI in high molar activity (A m ) is well-established and has been automated. [54][55][56][57] To date, this labelled reagent is mainly employed for the electrophilic 18 F-fluoromethylation of phenols.…”

Imaging cardiac SCN5A using the novel F-18 radiotracer radiocaine

“…Lidocaine exhibits micromolar affinity for SCN5A and provided a structural basis for PET radiotracer development. Typically, PET radiotracer design is biased toward higher affinity (low nM) compounds in order to adequately provide signal to background contrast, in particular for low-density targets 16 . However, we recognized that low affinity could be advantageous for SCN5A for two primary reasons: (1) SCN5A density is high in the myocardium and (2) faster dissociation kinetics would accelerate reaching binding equilibrium conditions.…”