Assessment of Allodynia Relief by Tissue-Protective Molecules in a Rat Model of Nerve Injury-Induced Neuropathic Pain - Tissue-Protective Cytokines: Methods and Protocols - page 187

sciatic nerve, its branches, or the vessels that are situated in
that area.
18. Identify tibial, common peroneal and caudal cutaneous sural
nerve (Fig. 1c ). The tibial and common peroneal will be the
nerves that are going to be transected. The cutaneous sural
nerve will be spared.
19. Carefully free tibial and common peroneal nerve from their
surroundings with a cotton swab.
20. Place the curved Moria iris forceps under the tibial nerve and
use it to guide a 5-0 suture to pass under the nerve. Ligate the
nerve at approximately 1 cm distal from the trifurcation.
21. Repeat the previous step for the common peroneal nerve and
ligate with 5-0 suture at approximately 1 cm distal from the
trifurcation.
22. Lift the tibial nerve with the curved Moria forceps closed and
allow the forceps to open to have the nerve form a bridge of
about 4 mm between the two legs of the forceps.
23. Cut the nerve approximately 4 mm from the ligature (see Note 3).
24. Lift the tibial nerve and cut away approximately 3 mm of nerve
distal from the suture.
25. Lift the common peroneal nerve with the curved Moria for-
ceps closed and allow the forceps to open to have the nerve
form a bridge of about 4 mm between the two legs of the
forceps.
26. Cut the nerve approximately 4 mm from the ligature (see Note 4).
27. Lift the common peroneal nerve and cut away approximately
3 mm of nerve distal from the suture.
28. Carefully displace the proximal nerve stumps with a cotton
swab.
29. Restore muscle integrity and suture the fascia with 5-0 silk
suture
30. Close skin with four 4-0 nylon sutures.
31. Allow animal to awake and monitor for 30-60 min under a
heating source maintained at 38°C.
32. Transfer the animal to a cage with fresh sawdust, food and
water available. Animals can be housed 2 per cage.

3.2 Assessment
of Pain: Tactile
Allodynia

1. Place the animal in the Perspex cage on the grid and allow to
acclimatize for 10-20 min.
2. Stimulate the hind paw with the Semmes-Weinstein
monofilaments just lateral from the midline. Maintain the
filament perpendicular to the paw. Start with the filament that
applies the lowest amount of force (1,65). Apply at a rate of
1 Hz to a total of ten stimuli.