Fig. 1.

CCD increased the flinch responses evoked by intracutaneous injection of α,β-meATP. The flinching behavior was assessed by determining paw lift time per minute (PLTPM). The maximal flinch responses occurred at 1 min, and responses were completely diminished 10 min after the injection of α,β-meATP (50 nmol). The PLTPM at peak was ~twofold longer in CCD rats (right) than in sham-operated rats (left). The P2X receptor antagonist TNP–ATP (200 nmol) attenuated the flinch responses when co-injected with α,β-meATP. PBS did not produce any significant flinch responses. All rats received a single injection of 50 μl. n = 6 animals for all groups.