PMID- 23010256
OWN - NLM
STAT- MEDLINE
DCOM- 20131202
LR  - 20211021
IS  - 1488-2434 (Electronic)
IS  - 1180-4882 (Print)
IS  - 1180-4882 (Linking)
VI  - 38
IP  - 2
DP  - 2013 Mar
TI  - Dopamine D2 and D3 binding in people at clinical high risk for schizophrenia, 
      antipsychotic-naive patients and healthy controls while performing a cognitive 
      task.
PG  - 98-106
LID - 10.1503/jpn.110181 [doi]
AB  - BACKGROUND: The dopamine (DA) D2 receptors exist in 2 states: a high-affinity 
      state (D2 high) that is linked to second messenger systems, responsible for 
      functional effects, exhibits high affinity for agonists (e.g., DA), and a 
      low-affinity state that is functionally inert exhibits lower affinity for 
      agonists. The DA D3 receptor subtype exhibits high agonist affinity, whereas the 
      existence of the multiple affinity states is controversial. Preclinical studies 
      in animal models of psychosis have shown a selective increase of D2 high as the 
      common factor in psychosis, and the D3 receptor has been suggested to be involved 
      in the pathophysiology of schizophrenia. METHODS: We studied D2 high and D3 in 
      people at clinical high risk (CHR) for schizophrenia and in antipsychotic-naive 
      patients with schizophrenia using the novel positron emission tomography 
      radiotracer, [11C]-(+)-PHNO. The binding potential nondisplaceable (BP(ND)) was 
      examined in the regions of interest (ROI; caudate, putamen, ventral striatum, 
      globus pallidus, substantia nigra and thalamus) using an ROI and a voxel-wise 
      approach while participants performed a cognitive task. RESULTS: We recruited 12 
      CHR individuals and 13 antipsychotic-naive patients with schizophrenia-spectrum 
      disorder, whom we compared with 12 age- and sex-matched healthy controls. The 
      BP(ND) between patients and controls did not differ in any of the ROIs, 
      consistent with the voxel-wise analysis. Correlations between the BP(ND) in 
      D3-rich regions and psychopathology warrant further investigation. LIMITATIONS: 
      In the absence of resting-state (baseline) BP(ND) data, or following a depletion 
      paradigm (i.e., alpha-methyl partyrosine), it is not possible to ascertain whether 
      the lack of difference among the groups is owing to different levels of baseline 
      DA or to release during the cognitive task. CONCLUSION: To our knowledge, the 
      present study represents the first effort to measure the D2 and D3 receptors 
      under a cognitive challenge in individuals putative/prodromal for schizophrenia 
      using [11C]-(+)-PHNO.
FAU - Suridjan, Ivonne
AU  - Suridjan I
AD  - PET Centre, Centre for Addiction and Mental Health, Toronto, Ont.
FAU - Rusjan, Pablo
AU  - Rusjan P
FAU - Addington, Jean
AU  - Addington J
FAU - Wilson, Alan A
AU  - Wilson AA
FAU - Houle, Sylvain
AU  - Houle S
FAU - Mizrahi, Romina
AU  - Mizrahi R
LA  - eng
GR  - U01 MH066134/MH/NIMH NIH HHS/United States
GR  - U01MH066134/MH/NIMH NIH HHS/United States
GR  - MOP-74702/CAPMC/CIHR/Canada
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
PL  - Canada
TA  - J Psychiatry Neurosci
JT  - Journal of psychiatry & neuroscience : JPN
JID - 9107859
RN  - 0 (Dopamine Agonists)
RN  - 0 (Oxazines)
RN  - 0 (Receptors, Dopamine D2)
RN  - 0 (Receptors, Dopamine D3)
RN  - 22Z7E0X6OF (naxagolide)
SB  - IM
MH  - Adolescent
MH  - Adult
MH  - Brain/*diagnostic imaging/metabolism
MH  - Case-Control Studies
MH  - Cognition/*physiology
MH  - Dopamine Agonists
MH  - Female
MH  - Humans
MH  - Magnetic Resonance Imaging
MH  - Male
MH  - Oxazines
MH  - Positron-Emission Tomography/methods
MH  - Receptors, Dopamine D2/*metabolism
MH  - Receptors, Dopamine D3/metabolism
MH  - Schizophrenia/*diagnostic imaging/metabolism
MH  - Young Adult
PMC - PMC3581597
EDAT- 2012/09/27 06:00
MHDA- 2013/12/16 06:00
PMCR- 2013/03/01
CRDT- 2012/09/27 06:00
PHST- 2012/09/27 06:00 [entrez]
PHST- 2012/09/27 06:00 [pubmed]
PHST- 2013/12/16 06:00 [medline]
PHST- 2013/03/01 00:00 [pmc-release]
AID - 10.1503/jpn.110181 [pii]
AID - pg98 [pii]
AID - 10.1503/jpn.110181 [doi]
PST - ppublish
SO  - J Psychiatry Neurosci. 2013 Mar;38(2):98-106. doi: 10.1503/jpn.110181.