Fig. 4. Effect of chronic spinal transection on hind limb movement forces under isoflurane. ( A ) Individual example of hind limb movement forces elicited by supramaximal noxious mechanical stimulation of the forepaw ( top two traces ), hind paw ( middle two traces ,) and tail ( bottom two traces ) in a 28-day chronic spinal animal. Responses to forepaw clamp were repetitive and robust; however, responses to hind paw and tail clamp consisted of only single weak hind limb withdrawals at the onset or offset of clamp removal. ( B ) Mean force integrals, or area under the curve (AUC), elicited by tail, hind paw, and forepaw clamping at 0.6 and 0.8 minimum alveolar concentration (MAC). Solid black bars represent mean left limb force integral, and shaded bars represent mean right limb force integral. LFL = left forelimb; = right forelimb; RFL = right forelimb; LHL = left hind limb; RHL = right hind limb. * Significantly reduced hind limb forces compared with hind limb forces in cold-block animals after cooling (see “rewarm,” fig. 3B ) . Error bars = mean ± SD.