Myelinated Afferents Are Involved in Pathology of the Spontaneous Electrical Activity and Mechanical Hyperalgesia of Myofascial Trigger Spots in Rats

Figure 3

Mechanical pain thresholds at MTrSs/non-MTrSs that evoked ipsilateral hind-limb nociceptive withdrawal reflex (NWR). “#” represents, before the TTX injection, MPTs at MTrSs were significantly lower than those at non-MTrSs (). “@” represents, 5 min, 15 min, and 30 min after the TTX injection, MPTs at MTrSs increased significantly (). “” represents, 5 min after the TTX injection, MPTs at non-MTrSs decreased (). “!” represents, 15 min and 30 min after the TTX injection, MPTs at non-MTrSs were higher than those at non-MTrSs before injection, but the differences did not reach the significant level (). “&” represents, 30 min after TTX injection, MPTs at MTrSs were significantly lower than those at non-MTrSs ().