抄録
We examined the effects of one-night sleep deprivation (SD) on the brain GABAA receptor binding using PET with macaque monkeys(macaca mulatta). Monkeys were trained in a continuous simple reaction task (CSRT), which is required to repeat a visual-guided lever pressing, until they had been skillful in performing the task by a long-term training. The reaction time (RT) which is required for responding to the visual cue and for repeating trials was measured to estimate the behavioral performance. To measure the binding activity of the GABAA receptor, two 11C-labeled benzodiazepine analogues, [11C]Ro15-4513 and [11C]Ro15-1788, were used. Parametric images of the binding potential (BP) which were generated by a simplified reference tissue model (SRTM) based on pixel-wise kinetic modeling using a time activity curve of the pons as a reference were statistically analyzed using SPM99 software. RT for CSRT was significantly prolonged by the SD. BPs of [11C]Ro15-4513, but not of [11C]Ro15-1788, in the limbic structures such as the anterior cingulate and amygdala were significantly increased by SD. In addition, BPs of [11C]Ro15-4513 in the mediodorsal nucleus of thalamus was changed dependent on the performance state that was estimated by the reaction time of CSRT. These results strongly indicate that changes of behavioral performance state caused by SD might be associated with changes in GABAergic neurotransmission in the limbic structure and the mediodorsal nucleus of thalamus. [J Physiol Sci. 2007;57 Suppl:S41]
