- 作者：Alice Egerton ; Christopher A. Chaddock ; Toby T. Winton-Brown ; Michael A.P. Bloomfield ; Sagnik Bhattacharyya ; Paul Allen ; Philip K. McGuire ; Oliver D. Howes
- 关键词：Dopamine ; imaging ; positron emission tomography ; psychosis ; schizophrenia ; striatum
- 刊名：Biological Psychiatry
- 出版年：2013
- 出版时间：15 July, 2013
- 年：2013
- 卷：74
- 期：2
- 页码：106-112
- 全文大小：146 K
Background
Using positron emission tomography (PET), we previously observed increases in 3,4-dihydroxy-6-[18F]fluoro-L-phenylalanine (18F-DOPA) uptake in the striatum of subjects at ultra-high risk (UHR) for psychosis, indicating elevated presynaptic dopamine synthesis capacity. The purpose of this study was to test if this finding would be replicated in a second UHR cohort.Methods
18F-DOPA PET was used to estimate dopamine synthesis capacity in the striatum of an entirely new cohort of 26 individuals at UHR for psychosis (14 males, mean¡ÀSD age = 22.7¡À4.7 years) and 20 healthy volunteers matched for age and gender (11 males, mean¡ÀSD age = 24.5¡À4.5 years).
Results
Dopamine synthesis capacity was elevated in the whole [t(44) = 2.6; p = .01, effect size = .81] and associative striatum [t(44) = 2.6; p = .01, effect size = .73] of UHR compared with control subjects. When the two samples were combined to give a final sample of 32 control and 50 UHR subjects, the higher levels of dopamine synthesis capacity in the UHR group reached significance across the whole [F(1,81) = 11.0; p = .001], associative [F(1,81) = 12.7; p = .001], and sensorimotor [F(1,81) = 4.7; p = .03], but not the limbic [F(1,81) = 2.1; p = .2], striatum.
Conclusions
The findings indicate that elevated dopamine synthesis capacity in the dorsal striatum is a robust feature of individuals at UHR for psychosis and provide further evidence that dopaminergic abnormalities precede the onset of psychosis.