Challenges and Recent Advances in Mass Spectrometric Imaging of Neurotransmitters

Abstract

Mass spectrometric imaging (MSI) is a powerful tool that grants the ability to investigate a broad mass range of molecules, from small molecules to large proteins, by creating detailed distribution maps of selected compounds. To date, MSI has demonstrated its versatility in the study of neurotransmitters and neuropeptides of different classes toward investigation of neurobiological functions and diseases. These studies have provided significant insight in neurobiology over the years and current technical advances are facilitating further improvements in this field. neurotransmitters, focusing specifically on the challenges and recent Herein, we advances of MSI of neurotransmitters.

Imaging Mass Spectrometric Analysis of Neurotransmitters

“…29) Neuropeptides can be either excitatory or inhibitory neurotransmitters and thus, play seemingly antagonistic roles in various conditions, from euphoria 30) and pain reduction, 31) to anxiety 32) and panic attacks. 33) In the last 40 years, mass spectrometry has been a reliable tool to identify and quantify neuropeptides in samples from various sources.…”

“…One such problem is the need for proper sample preparation to minimise rapid molecular degradation. 29) In addition, most of the time matrices are required for MALDI analyses, but its use renders sample preparation more elaborate, and prevents the analyses of samples in their native form. Matrix selection and deposition on samples are critical to obtain high sensitivity, spatial resolution and speci c ionisation of sample analytes.…”

“…Glutamate, γ-aminobutyric acid (GABA), and serine, amongst others, are considered amino acids capable of transmitting these signals. 29) In the classic view, glutamate is the major mediator of excitatory signalling in the CNS, 44) whereas GABA is an inhibitory neurotransmitter. 45) Nonetheless, Chavas and Marty 46) recently showed that a dual role (inhibition and excitation) of GABA was found in the cerebellar interneuron network.…”

Is the Pen really Mightier than the Scalpel?

“…It has a greater advantage of being used for clinical or field application, as it is portable. 6 The major drawback of this technique is that it cannot be used for in vivo analysis as it includes use of organic solvent sprays, high-pressure nebulizing gas, and high voltages. 3,7,8 It is also known to have lower spatial resolution (180-200 μm).…”

“…3,7,8 It is also known to have lower spatial resolution (180-200 μm). 6 The MS coupled with ultraviolet lasers and infrared lasers is a laser desorption ionization (LDI)-MS analysis. Since it is reported that the ablation of thin tissue sections with lasers produces a characteristic phospholipid ion population, the laser surgery combined with MS detection can potentially be used during surgical interventions for the real-time, in situ identification of tissues.…”