Spinal Bicuculline Produces Hypersensitivity of Dorsal Horn Neurons: Effects of Excitatory Amino Acid Antagonists
August 1998
in “
Pain
”
TLDR Blocking GABA(A) receptors increases neuron sensitivity, showing GABA and glycine have different roles in pain.
The study investigated the effects of GABAA receptor antagonism using bicuculline on dorsal horn neurons in anesthetized cats. Bicuculline increased evoked activity in nociceptive neurons, particularly affecting responses to hair deflection and mechanical stimulation. It also increased background discharge and afterdischarge to noxious stimuli. The study found that co-administration of an NMDA receptor antagonist (AP-7) did not affect the bicuculline-enhanced responses, whereas a non-NMDA receptor antagonist (CNQX) blocked mechanical input. These findings highlighted differences in the roles of GABA and glycine in spinal dorsal horn inhibitory control, suggesting distinct components of neuropathic pain modulation.
