We have demonstrated that purinergic and NMDA receptor mechanisms are involved in the mustard oil (MO)-induced neuroplastic changes reflecting central sensitization in nociceptive neurons in trigeminal subnuclei caudalis (Vc; medullary dorsal horn) and oralis (Chiang et al. SfN Abst 175.14, 2003; Hu et al. J Neurophysiol 88:1614, 2002). This study tested whether Vc central sensitization induced by MO application to the tooth pulp depends on the functional integrity of glia by the use of a glia Kreb cycle blocker, sodium fluoroacetate (FA). Extracellular recordings of single neuronal activity were made from nociceptive-specific and wide dynamic range neurons in the deep Vc laminae in urethane/alpha-chloralose-anesthetized adult rats. The mechanoreceptive field (RF), mechanical activation threshold and responses to graded pinch or pressure of each neuron were assessed as baseline values. Then 2 assessments were made at 5 and 15 min after superfusion (i.t., 0.6 ml/hr for 50 min) of FA (1-10 mM) or saline (as ...