Laser Doppler Flowmetry to Study the Regulation of Cerebral Blood Flow by G Protein-Coupled Receptors in Rodents

  • Xavier Toussay
  • Mario Tiberi
  • Baptiste LacosteEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1947)


A large body of evidence suggests that G protein-coupled receptors (GPCRs) play an important role in the regulation of peripheral vascular reactivity. Meanwhile, the extent of GPCR influence on the regulation of brain vascular reactivity, or cerebral blood flow (CBF), has yet to be fully appreciated. This is of physiological importance as the modulation of CBF depends on an intricate interplay between neurons, astrocytes, pericytes, and endothelial cells, all of which partaking in the formation of a functional entity referred to as the neurovascular unit (NVU). The NVU is the anatomical substrate of neurovascular coupling (NVC) mechanisms, whereby increased neuronal activity leads to increased blood flow to accommodate energy, oxygen, and nutrients demands. In light of growing evidence showing impaired NVC in several neurological disorders, and the fact that GPCRs represent the most important targets of FDA-approved drugs, it is of utmost importance to use experimental approaches to study GPCR-induced regulation of NVC for the future development of pharmaceutical compounds that could normalize CBF function. Herein, we describe a minimally invasive approach called laser Doppler flowmetry (LDF) that, when used in combination with a whisker stimulation paradigm in rodents, allows gauging blood perfusion in activated cerebral cortex. We comprehensively explain the surgical procedure and data acquisition in mice, and discussed about important experimental considerations for the study of CBF regulation by GPCRs using pharmacological agents.

Key words

Laser doppler flowmetry Cerebral blood flow GPCRs Rodents Physiology 


  1. 1.
    Wootten D et al (2018) Mechanisms of signalling and biased agonism in G protein-coupled receptors. Nat Rev Mol Cell Biol 19:638–653CrossRefGoogle Scholar
  2. 2.
    Rosenbaum DM, Rasmussen SG, Kobilka BK (2009) The structure and function of G-protein-coupled receptors. Nature 459(7245):356–363CrossRefGoogle Scholar
  3. 3.
    Venkatakrishnan AJ et al (2013) Molecular signatures of G-protein-coupled receptors. Nature 494(7436):185–194CrossRefGoogle Scholar
  4. 4.
    Husted AS et al (2017) GPCR-mediated signaling of metabolites. Cell Metab 25(4):777–796CrossRefGoogle Scholar
  5. 5.
    Vass M et al (2018) Chemical diversity in the G protein-coupled receptor superfamily. Trends Pharmacol Sci 39(5):494–512CrossRefGoogle Scholar
  6. 6.
    Hauser AS et al (2017) Trends in GPCR drug discovery: new agents, targets and indications. Nat Rev Drug Discov 16(12):829–842CrossRefGoogle Scholar
  7. 7.
    Hauser AS et al (2018) Pharmacogenomics of GPCR drug targets. Cell 172(1–2):41–54.e19CrossRefGoogle Scholar
  8. 8.
    Sriram K, Insel PA (2018) G protein-coupled receptors as targets for approved drugs: how many targets and how many drugs? Mol Pharmacol 93(4):251–258CrossRefGoogle Scholar
  9. 9.
    Andreone BJ, Lacoste B, Gu C (2015) Neuronal and vascular interactions. Annu Rev Neurosci 38:25–46CrossRefGoogle Scholar
  10. 10.
    Cauli B, Hamel E (2010) Revisiting the role of neurons in neurovascular coupling. Front Neuroenerg 2:9CrossRefGoogle Scholar
  11. 11.
    Lecrux C, Hamel E (2011) The neurovascular unit in brain function and disease. Acta Physiol (Oxf) 203(1):47–59CrossRefGoogle Scholar
  12. 12.
    Micheels J, Alsbjorn B, Sorensen B (1984) Laser doppler flowmetry. A new non-invasive measurement of microcirculation in intensive care? Resuscitation 12(1):31–39CrossRefGoogle Scholar
  13. 13.
    Rajan V et al (2009) Review of methodological developments in laser Doppler flowmetry. Lasers Med Sci 24(2):269–283CrossRefGoogle Scholar
  14. 14.
    Bonner R, Nossal R (1981) Model for laser Doppler measurements of blood flow in tissue. Appl Opt 20(12):2097–2107CrossRefGoogle Scholar
  15. 15.
    Fredriksson I, Fors C, Johansson J (2007) Laser doppler flowmetry—a theoretical framework. Department of Biomedical Engineering, Linköping University, Linköping. Scholar
  16. 16.
    Lacoste B et al (2013) Cognitive and cerebrovascular improvements following kinin B1 receptor blockade in Alzheimer'’ disease mice. J Neuroinflammation 10:57CrossRefGoogle Scholar
  17. 17.
    Toussay X et al (2013) Locus coeruleus stimulation recruits a broad cortical neuronal network and increases cortical perfusion. J Neurosci 33(8):3390–3401CrossRefGoogle Scholar
  18. 18.
    Maguire JJ, Davenport AP (2005) Regulation of vascular reactivity by established and emerging GPCRs. Trends Pharmacol Sci 26(9):448–454PubMedGoogle Scholar
  19. 19.
    Magalhaes AC, Dunn H, Ferguson SS (2012) Regulation of GPCR activity, trafficking and localization by GPCR-interacting proteins. Br J Pharmacol 165(6):1717–1736CrossRefGoogle Scholar
  20. 20.
    Eichel K, von Zastrow M (2018) Subcellular organization of GPCR Signaling. Trends Pharmacol Sci 39(2):200–208CrossRefGoogle Scholar
  21. 21.
    Larach DR, Schuler HG (1991) Direct vasodilation by sevoflurane, isoflurane, and halothane alters coronary flow reserve in the isolated rat heart. Anesthesiology 75(2):268–278CrossRefGoogle Scholar
  22. 22.
    Schwinn DA, McIntyre RW, Reves JG (1990) Isoflurane-induced vasodilation: role of the alpha-adrenergic nervous system. Anesth Analg 71(5):451–459CrossRefGoogle Scholar
  23. 23.
    Endoh H et al (2001) Cerebral autoregulation during sevoflurane or isoflurane anesthesia: evaluation with transient hyperemic response. Masui 50(12):1316–1321PubMedGoogle Scholar
  24. 24.
    Crystal GJ, Salem MR (2003) Isoflurane causes vasodilation in the coronary circulation. Anesthesiology 98(4):1030CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Xavier Toussay
    • 1
    • 2
  • Mario Tiberi
    • 1
    • 2
  • Baptiste Lacoste
    • 1
    • 2
    Email author
  1. 1.Ottawa Hospital Research Institute (Neurosciences)OttawaCanada
  2. 2.Department of Cellular and Molecular Medicine, University of Ottawa Brain and Mind Research InstituteUniversity of OttawaOttawaCanada

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