Table 2.
Main results of TSPO PET/SPECT studies in Schizophrenia.
| Radiotracer | Population | m/f (%males) |
Age Range (mean) |
Main Information | TSPO Methodology: Scan Acquisition and Analysis | Main Results | Reference |
|---|---|---|---|---|---|---|---|
| 11C-PBR28 | 8 HAB-FEP 8 MAB-FEP 9 HAB-HC 7 MAB-HC |
FEP: 11/5 HC: 7/9 |
FEP: (28) HC: (26) |
Nicotine 2 in FEP 0 in HC FEP: 5 with benzodiazepine treatment |
0–91 min VT |
FEP < HC: F, T, Hipp | [106] |
| 11C-DPA-713 | 8 HAB-SCZ 4 MAB-SCZ 2 LAB-SCZ 9 HAB-HC 5 MAB-HC 2 LAB-HC |
SCZ: 11/3 (79) HC: 9/7 (56) |
SCZ: (24) HC: (25) |
Nicotine: 2 in HC 3 in SCZ SCZ: 2 unmedicated (last month) 1 with two antipsychotic 11 with one antipsyxchotic [range: 0–1119 chlorpromazine equivalent] |
0–90 min VT Logan |
LAB were excluded. HAB-SCZ = HAB-HC MAB-SCZ = MAB-HC |
[107] |
| 18F-FEPPA | 14 HAB-FEP 5 MAB-FEP 14 HAB-HC 6 MAB-HC |
FEP: 12/19 (63) HC: 9/11 (45) |
FEP: (28) HC: (28) |
FEP: 14 antipsychotic naïve, 5 unmedicated (last 4 weeks) |
0–125 min VT |
HAB-FEP = HAB-HC
MAB-FEP = MAB-HC |
[108] |
| 18F-FEPPA | 10 HAB-SCZ 6 MAB-SCZ 1 LAB-SCZ 19 HAB-HC 8 MAB-HC 0 LAB-HC |
SCZ. 10/6 HC: 10/17 |
SCZ: (43) HC: (44) |
SCZ: 16 with antipsychotics and others (antidepressants…) | 0–125 min VT |
HAB-SCZ = HAB-HC
MAB-SCZ = MAB-HC |
[110] |
| 11C-PK11195 | 16 SCZ 16 HC |
11/5 11/5 |
(33) (33) |
Nicotine 11 in SCZ 0 in HC SCZ: 8 antipsychotic-free |
0–60 min BPSRTM with RefCE |
Nicotine status SCZ > HC BPSRTM SCZ antipsychotic-free = HC SCZ > SCZ antipsychotic-free (83% of increase but p = 0.097) |
[109] |
| 11C-PK11195 | 19 SCZ 17 HC |
16/3 14/3 |
(24) (47) |
Nicotine 13 in SCZ 5 in HC SCZ: 4 antipsychotic-free, 16 with antipsychotic |
60 min BPSRTM with RefCluster Analysis |
SCZ = HC | [113] |
| 11C-PBR28 | 7 HAB-UHR 7 MAB-UHR 10 HAB-HC 4 MAB-HC 13 HAB-SCZ 1 MAB-SCZ 14 HAB-HC |
UHR: 7/7 (50) HC: 4/10 SCZ: 3/12 3/12 |
UHR: (24) HC: (28) SCZ: (47) (46) |
2 UHR with citalopram by the past | 0–90 min. DVR (VT target/VT whole brain) |
UHR > HC: Gm, F, T UHR excluding 2 subjects with citalopram > HC: F HAB-UHR > HAB-HC: Gm MAB-UHR > MAB-HC: Gm SCZ > HC: F, T UHR: Positive correlations between the mean PBR28 DVR and CAARMS |
[105] |
The TSPO density was evaluated in several studies using different radioligands, population characteristics and methods of analyses. Ref is the reference region. The RefCluster Analysis means that authors used a cluster analysis to extract voxels with normal ligand kinetics to serve as the reference input function. Empty spaces in the table correspond to data not clearly given in papers. Current abbreviations: SZC, patients with schizophrenia; DVR, distribution volume ratio; FEP, first episode patients; HAB, high-affinity binders; HC, healthy control; LAB, low-affinity binders; MAB, mix affinity binders; UHR, ultra-high-risk patients; VT, volume of distribution. List of brain areas abbreviations: F, frontal cortex areas; Hipp, hippocampus; T, temporal cortex area.