Fig. 4. Percent reduction in hyperalgesia (top ) and allodynia (bottom ) from intrathecal injection of adenosine as a function of time of the second capsaicin injection compared with intrathecal adenosine administration. Each symbol represents the mean ± SE of six volunteers. For hyperalgesia and for allodynia, the reduction in area from adenosine was statistically similar when the second capsaicin injection was administered from 30 min to 24 h after adenosine.