Aim: Hippocampal long-term potentiation (LTP), an activity-dependent plasticity in synaptic transmission, is believed as a fundamental mechanism of learning and memory. This form of plasticity also exists in spinal dorsal horn. Our previous work showed that electrical as well as natural noxious stimulation of afferent C-fibers or acute injury of the sciatic nerve produces LTP of C-fiber evoked field potentials in spinal dorsal horn. Aim: Hippocampal long-term potentiation (LTP), an activity-dependent plasticity in synaptic transmission, is believed as a fundamental mechanism of learning and memory. This form of plasticity also exists in spinal dorsal horn. Our previous work showed that electrical as well as natural noxious stimulation of afferent C-fibers or acute injury of the sciatic nerve produces LTP of C-fiber evoked field potentials in spinal dorsal horn.