PET evidence of central GABAergic changes in stiff-person syndrome

We measured expression of central nervous system GABA-A receptors with 11C-flumazenil (11C-FMZ) and PET in two subjects with stiff person syndrome (SPS). We found reduced 11C-FMZ binding potential (BP) in motor-premotor cortex, and increased 11C-FMZ BP in the cerebellar nuclei. This is the first in vivo PET evidence of central GABA-A receptors dysfunction in SPS, possibly concurring to the motor symptoms.