Optical Modulation of Metabotropic Glutamate Receptor Type 5 In Vivo Using a Photoactive Drug

  • Marc López-Cano
  • Joan Font
  • Amadeu Llebaria
  • Víctor Fernández-Dueñas
  • Francisco CiruelaEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1947)


Optopharmacology is a very promising approach based on the use of light-deliverable drugs, which allows manipulating physiological processes with high spatiotemporal resolution. Light-dependent drugs (i.e. caged-compounds) targeting G protein-coupled receptors (GPCRs) have been developed to provide great pharmacological precision on the control of pain. Metabotropic glutamate type 5 (mGlu5) receptors are widely expressed through the pain neuraxis and play a key role in pain transmission. In line with this, selective mGlu5 receptor negative allosteric modulators (NAMs) have consistently shown analgesic activity in experimental animal models of inflammatory pain. Accordingly, we synthesized a light-deliverable drug (i.e. caged compound) using the chemical structure of raseglurant, a mGlu5 receptor NAM, as a molecular scaffold. And thereafter, we evaluated the analgesic activity of the caged compound in formalin-injected (hind paw) mice upon light irradiation (405 nm). Of note, light was both delivered at the peripheral (i.e. hind paw) and central level (i.e. thalamus), by means of brain-implanted fiber-optics. The novel light-deliverable drug, JF-NP-26, showed antinociceptive activity upon violet light irradiation either of the hind paw or the thalamus, demonstrating the ability of precisely activating, in time and space, the caged compound. Here, we describe in detail the protocol used to perform a reliable and reproducible formalin nociception test in mice using an optopharmacology approach (i.e. light-deliverable compounds).

Key words

mGlu5 receptor Optopharmacology Pain Analgesia Mice 



This work was supported by MINECO/ISCIII (SAF2017-87349-R and PIE14/00034), the Catalan government (2017 SGR 1604), Fundació la Marató de TV3 (Grant 20,152,031), FWO (SBO-140028) to FC. MINECO (PCIN-2013-017-C03-01 and CTQ2014-57020-R), the Catalan government (2014SGR109 and 2014CTP0002) to AL. We thank Esther Castaño and Benjamín Torrejón, from the CCiT-Bellvitge Campus of the University of Barcelona for the technical assistance.


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Copyright information

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

Authors and Affiliations

  • Marc López-Cano
    • 1
    • 2
  • Joan Font
    • 3
  • Amadeu Llebaria
    • 3
  • Víctor Fernández-Dueñas
    • 1
    • 2
  • Francisco Ciruela
    • 1
    • 2
    Email author
  1. 1.Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina i Ciències de la Salut, IDIBELL, L’Hospitalet de LlobregatUniversitat de BarcelonaBarcelonaSpain
  2. 2.Institut de NeurociènciesUniversitat de BarcelonaBarcelonaSpain
  3. 3.MCS, Laboratory of Medicinal ChemistryInstitute for Advanced Chemistry of Catalonia (IQAC-CSIC)BarcelonaSpain

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