Neuropathic pain

PAIN

Porsolt offers models of acute and chronic pain and inflammation matching the needs of the industry and maintaining a recognized expertise, which addresses pain therapeutic endpoints and pain associated symptoms and side effects.

Neuropathic pain

SURGICAL MODELS

Chung / SNL and Bennett / CCI model of neuropathic pain in the rat

Surgery is performed according to Chung /SNL or Bennett/CCI protocol. When the chronic pain state is fully established, rats are submitted to a pre-test (electronic von Frey) of the hind paws to confirm neuropathic pain. On Testing days, only the lesioned paw is evaluated. Electronic von Frey, plantar, pinchmeter and cold plate tests are proposed as pain endpoint after dosing.

A baseline (except in the cold plate test) is performed before dosing and data are usually expressed using the difference between test and baseline measurement.  

Several pain measures can be used:
> Thermal stimulation (heat hyperalgesia or cold allodynia): measured using the Hargreaves method or the cold plate test (4°C), respectively.
> Tactile stimulation (tactile allodynia or tactile hyperalgesia): measured using an electronic von Frey apparatus or a pinchmeter.

And non-evoked pain measures:
> Activity meter
> Rotarod
> Neurological score

Plantar, Cold Plate, Electronic Von Frey, Pinchmeter Morphine i.p. yes
Plantar, Cold Plate, Electronic Von Frey, Pinchmeter Tramadol i.p. yes
Plantar, Cold Plate, Electronic Von Frey, Pinchmeter Pregabalin p.o. yes
Plantar, Cold Plate, Pinchmeter Duloxetine p.o. yes
BENNETT/CHUNG IN THE RAT
MEASURE REFERENCE ROUTE EFFECT*

* Positive effects are observed on selected measures

Modified Bennett/CCI model in the mouse

Surgery is performed according to a modified Bennett/CCI protocol. Mice are submitted to a pre-test (electronic von Frey) of the hind paws to verify neuropathic pain. Electronic von Frey and pinchmeter tests are proposed as pain endpoint after dosing.

CHEMOTHERAPY MODEL

Vincristine-induced neuropathic pain in the rat

Vincristine is administered daily (except for week-end) during a period of 11 days. Rats are submitted to a pre-test (electronic von Frey) of the hind paws to confirm neuropathic pain. Electronic von Frey test is proposed as pain endpoint after dosing.