Formalin (automated test)

  • Presentation


    Formalin test in mice is considered to better mirror clinical conditions of pain than tests that use a brief and high intensity mechanical or thermal stimulation and measure spinal-mediated reflex responses.
    As in the clinical setting, the pain induced by the injection of dilute formalin solution is persistent (tonic) and comprises neurogenic and inflammatory components.

  • Compound testing


    Painkillers or anti-inflammatory drugs are usually tested in this model but other treatments could also be considered. Please feel free to contact us to discuss the feasibility of your study.

  • Endpoints


    ☐ Flinches

  • Validation data

  • Manual counting of pain behaviour by an observer is a hassle and time-consuming endeavour.
    NEUROFIT implements a system capable of automated detection of mouse flinches to measure pain behaviour.

    Injection of dilute formalin into mouse footpad elicits a typical biphasic nociceptive behaviour :



  • an early transient phase (0 - 5min) which is believed to be a consequence of direct stimulation of sensory nerve fibers and ...

    Morphin but not Gabapentin markedly reduces the early phase nociceptive response to Formalin.
    *, p < 0.05 as compared to untreated Formaline group



  • a late tonic phase (15 - 45min) which is believed to be a result of inflammatory response to Formalin-induced tissue injury

    Both Morphin and Gabapentin markedly suppress the late nociceptive response to Formalin.
    *, p < 0.05 as compared to untreated Formaline group

  • Gabapentin reduces in dose-dependent the pain behaviour response (flinches) to formalin injection in the mouse during the late tonic phase.

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