Research report Decreased benzodiazepine receptor density in the cerebellum of early blind human subjects

b ´ Abstract As a first approach to study the effect of early visual deprivation in the GABA-ergic inhibitory system, the distribution of 11 11 benzodiazepine receptors (BZR) was accurately estimated using ( C)flumazenil (( C)FMZ). Measurements were carried out in five 11 subjects who became blind early in life and in five sighted control subjects. The interactions between ( C)FMZ and BZR were described using a non-linear compartmental analysis which permitted to estimate the BZR synaptic density independently of other model parameters. The distribution of BZR in the visual areas and other cortical regions of blind subjects was qualitatively and quantitatively similar to that of controls. However, the BZR density in the cerebellum was significantly lower in blind than in control subjects (P,0.01). Our findings suggest that modifications of the cerebellar neural circuitry may be concomitant to the already observed compensatory reorganization in cerebral areas of blind subjects. © 2001 Elsevier Science B.V. All rights reserved. Theme: Neurotransmitters, modulators, transporters, and receptors