Gabapentin inhibits excitatory synaptic transmission in the hyperalgesic spinal cord

In the present study we tested the effects of the antihyperalgesic compound gabapentin on dorsal horn neurones in adult spinal cord. Slices were taken from control and hyperalgesic animals suffering from streptozocin-induced diabetic neuropathy. At concentrations up to 100 mu M, bath application fai led to affect the resting membrane properties of dorsal horn neurones taken from both groups of animal. In contrast, bath application of gabapentin dr amatically reduced the magnitude of the excitatory postsynaptic current (EP SC) in neurones taken from hyperalgesic animals without altering the magnit ude of the EPSC in control animals. Using a paired pulse stimulation protoc ol, together with analysis of miniature EPSC's, it was possible to demonstr ate that gabapentin mediated these effects via a pre-synaptic site of actio n.