Hind paw mechanical allodynia
To evaluate the development of mechanical allodynia, the mice were
individually placed in transparent boxes on a wire mesh platform
allowing easy access to the right hind paw plantar surface. Filaments of
different stiffness were applied to the plantar surface of the hind paw,
ranging from 0.07 to 2.0 g (0.07, 0.16, 0.40, 0.60, 1.0, 1.4, 2.0 g).
The mechanical threshold was obtained according to the up-and-down
paradigm [51].
This paradigm continued for a total of six measurements, or until four
consecutive positive or four consecutive negative responses occurred.
The mechanical paw-withdrawal threshold (in g) response was then
calculated from the resulting scores [18]. To determine the baseline
thresholds, the animals were acclimatized for 60 minutes before the test
and all animals were assessed before stress induction (baseline values).
The mechanical threshold was evaluated on days 1, 3, 7, 10 and 14 days.
Hind paw mechanical allodynia was also measured before ST or NST
induction (Basal), after ST or NST induction (7 days after), and 1 and 4
hours after BIBN4096BS/vehicle treatment.