Gabazine (GBZ)

Gabazine (SR-95531) is a drug that acts as an antagonist at GABAA receptors. It is used in scientific research and has no role in medicine, as it would be expected to produce convulsions if used in humans. Gabaminergic drugs (such as benzodiazepines and barbiturates) would likely antagonize gabazines effects, effectively functioning as antidotes.

Gabazine binds to the GABA recognition site of the receptor-channel complex and acts as an allosteric inhibitor of channel opening. The net effect is to reduce GABA-mediated synaptic inhibition by inhibiting chloride flux across the cell membrane, and thus inhibiting neuronal hyperpolarization. While phasic (synaptic) inhibition is gabazine-sensitive, tonic (extrasynaptic) inhibition is relatively gabazine-insensitive.