TY - JOUR

T1 - A systematic search and mapping review of studies on intracerebral microdialysis of amino acids, and systematized review of studies on circadian rhythms

AU - Leenaars, Cathalijn H.C.

AU - Freymann, Jennifer

AU - Jakobs, Koen

AU - Menon, Julia M.L.

AU - van Ee, Thomas J.

AU - Elzinga, Janneke

AU - Kempkes, Rosalie W.M.

AU - Zoer, Bea

AU - Drinkenburg, Pim W.H.I.M.

N1 - Funding Information: ZonMW (114024103), the DFG (FOR2591, BL 953/11-1) and the Federal State of Lower Saxony (R2N) provided funding for this project. The authors would like to thank Rob de Vries and Judith van Luijk for advice in protocol development, Alice Tillema for help in optimising the search strategy, and Judith van Luijk and Katya Tsaioun for assistance in screening. Publisher Copyright: © 2018 Ubiquity Press. All rights reserved.

PY - 2021

Y1 - 2021

N2 - Background: Microdialysis can be used to measure amino acids in the extracellular space in vivo, based on the principle of diffusion. Variations in experimental set-up result in variations in baseline levels of the compounds measured. Variations may also be due to circadian rhythms. Method: We systematically searched and mapped the literature on all studies reporting baseline microdialysis measurements of histamine and the amino acids asparagine, aspartate, GABA, glutamate, glutamine, glycine, proline and taurine. We fully reviewed the studies describing circadian rhythms for histamine and the selected amino acids. Results: We retrieved 2331 papers describing baseline measurements of one or more of the compounds of interest. We provide a numerical summary and lists of the publications by compound. We retrieved 11 references describing studies on the circadian rhythms of the compounds of interest. Aspartate, glutamate and histamine are generally higher during the dark than during the light phase in nocturnal rodents. For glutamine, no rhythmicity was observed. For GABA, the results were too inconsistent to generalise. For asparagine, glycine, proline and taurine, insufficient data are available. Conclusion: The literature on intracerebral microdialysis measurements of the amino acids is vast, but certain primary studies are still warranted. Future systematic reviews on the individual compounds can shed light on the effects of experimental variations on baseline concentrations.

AB - Background: Microdialysis can be used to measure amino acids in the extracellular space in vivo, based on the principle of diffusion. Variations in experimental set-up result in variations in baseline levels of the compounds measured. Variations may also be due to circadian rhythms. Method: We systematically searched and mapped the literature on all studies reporting baseline microdialysis measurements of histamine and the amino acids asparagine, aspartate, GABA, glutamate, glutamine, glycine, proline and taurine. We fully reviewed the studies describing circadian rhythms for histamine and the selected amino acids. Results: We retrieved 2331 papers describing baseline measurements of one or more of the compounds of interest. We provide a numerical summary and lists of the publications by compound. We retrieved 11 references describing studies on the circadian rhythms of the compounds of interest. Aspartate, glutamate and histamine are generally higher during the dark than during the light phase in nocturnal rodents. For glutamine, no rhythmicity was observed. For GABA, the results were too inconsistent to generalise. For asparagine, glycine, proline and taurine, insufficient data are available. Conclusion: The literature on intracerebral microdialysis measurements of the amino acids is vast, but certain primary studies are still warranted. Future systematic reviews on the individual compounds can shed light on the effects of experimental variations on baseline concentrations.

KW - Amino acids

KW - Circadian rhythm

KW - Histamine

KW - Microdialysis

KW - Systematic map

U2 - 10.5334/JCR.172

DO - 10.5334/JCR.172

M3 - Review

AN - SCOPUS:85071886230

VL - 16

JO - Journal of Circadian Rhythms

JF - Journal of Circadian Rhythms

SN - 1740-3391

IS - 1

M1 - 172

ER -