Resnick S M, Gur R E, Alavi A, Gur R C, Reivich M
PET Center, University of Pennsylvania, Philadelphia 19104.
Psychiatry Res. 1988 Apr;24(1):1-11. doi: 10.1016/0165-1781(88)90134-5.
Our previous observation of a disturbed subcortical-to-cortical gradient of activity in schizophrenia was further elucidated by examining glucose metabolism in three subcortical structures: lenticular nucleus, caudate nucleus, and thalamus. Local cerebral glucose metabolism was determined with 18F-fluorodeoxyglucose using positron emission tomography (PET) in a sample of 20 unmedicated schizophrenics and 18 normal volunteers. Repeated evaluations were performed for 12 schizophrenics following treatment with psychotropic medications and for 11 controls. Unmedicated schizophrenics had lower cortical and caudate absolute metabolic rates. Subcortical-to-cortical ratios for the lenticular nucleus and thalamus were increased in schizophrenics compared with controls, reflecting a preservation of activity in these structures relative to decreased cortical metabolism. When patients were grouped by length of medication-free period before the initial study, there was a trend for patients who had been medication free less than 6 months to have higher subcortical ratios. However, there were no consistent effects of medication in the subsample of patients whose PET studies were repeated following treatment. The results demonstrate relative hypermetabolism in structures implicated in dopamine pathways. An understanding of the physiological significance of this finding awaits the combined measurement of metabolic activity and neuroreceptors in schizophrenics.
通过检测三个皮质下结构（豆状核、尾状核和丘脑）的葡萄糖代谢情况，我们先前关于精神分裂症患者皮质下到皮质活动梯度紊乱的观察结果得到了进一步阐明。使用正电子发射断层扫描（PET）技术，以18F-氟脱氧葡萄糖测定了20名未接受药物治疗的精神分裂症患者和18名正常志愿者样本的局部脑葡萄糖代谢情况。对12名接受精神药物治疗后的精神分裂症患者和11名对照者进行了重复评估。未接受药物治疗的精神分裂症患者皮质和尾状核的绝对代谢率较低。与对照组相比，精神分裂症患者豆状核和丘脑的皮质下与皮质代谢率比值升高，这反映出相对于皮质代谢降低，这些结构中的活动得以保留。当根据初次研究前无药期的长短对患者进行分组时，无药期少于6个月的患者有皮质下比值较高的趋势。然而，在治疗后重复进行PET研究的患者亚组中，未发现药物有一致的影响。结果表明，与多巴胺通路相关的结构存在相对代谢亢进。对这一发现的生理意义的理解有待于对精神分裂症患者代谢活动和神经受体进行联合测量。
