scholarly journals D1-Dopamine Receptor Availability in First-Episode Neuroleptic Naive Psychosis Patients

2019 ◽  
Vol 22 (7) ◽  
pp. 415-425 ◽  
Author(s):  
Per Stenkrona ◽  
Granville J Matheson ◽  
Christer Halldin ◽  
Simon Cervenka ◽  
Lars Farde
Keyword(s):  
Positron Emission Tomography ◽  
Dopamine Receptor ◽  
Emission Tomography ◽  
First Episode ◽  
Control Subjects ◽  
Positron Emission ◽  
Significant Difference ◽  
D1 Dopamine Receptor ◽  
Dorsolateral Prefrontal ◽  
Dopamine Receptor Binding

Abstract Background Positron emission tomography studies examining differences in D1-dopamine receptor binding between control subjects and patients with schizophrenia have been inconsistent, reporting higher, lower, and no difference in the frontal cortex. Exposure to antipsychotic medication has been suggested to be a likely source of this heterogeneity, and thus there is a need for studies of patients at early stages of the disorder who have not been exposed to such drugs. Methods Here, we compared 17 healthy control subjects and 18 first-episode neuroleptic naive patients with schizophrenia or schizophreniform psychosis using positron emission tomography and the D1-dopamine receptor radioligand [11C]SCH23390. Results We observed a statistically significant difference in the dorsolateral prefrontal cortex. Contrary to our expectations, patients had less D1-dopamine receptor availability with a moderate effect size. In a Bayesian analysis, we show that the data are over 50 times more likely to have occurred under the decrease as opposed to the increase hypothesis. This effect was not global, as our analysis showed that the null hypothesis was preferred over either hypothesis in the striatum. Conclusions This investigation represents the largest single sample of neuroleptic-naive patients examined for D1-dopamine receptor availability using PET and suggests a reduction of prefrontal D1-dopamine receptor density in the pathophysiology of schizophrenia. However, further work will be required to reach a consensus.

D1 dopamine receptor binding in mood disorders measured by positron emission tomography

1992 ◽  
Vol 106 (1) ◽  
pp. 14-18 ◽  
Author(s):  
Tetsuya Suhara ◽  
Kazuhiko Nakayama ◽  
Osamu Inoue ◽  
Hiroshi Fukuda ◽  
Makoto Shimizu ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Mood Disorders ◽  
Dopamine Receptor ◽  
Receptor Binding ◽  
Emission Tomography ◽  
Positron Emission ◽  
D1 Dopamine Receptor ◽  
Dopamine Receptor Binding

Central D2 receptor blockade and antipsychotic effects of neuroleptics. Preliminary study with positron emission tomography

1990 ◽  
Vol 5 (4) ◽  
pp. 231-240 ◽  
Author(s):  
JL Martinot ◽  
ML Paillère-Martinot ◽  
C Loc'h ◽  
P Péron Magnan ◽  
B Mazoyer ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Dopamine Receptor ◽  
Negative Symptoms ◽  
Receptor Occupancy ◽  
Emission Tomography ◽  
Receptor Blockade ◽  
Low Doses ◽  
Receptor Density ◽  
Positron Emission ◽  
Significant Difference

SummaryThe striatal D2 receptor density/affinity index was assessed using positron emission tomography and 76Br-Bromolisuride in 15 schizophrenics, first untreated, and afterwards receiving neuroleptics, and in 14 control subjects. The patients received low or conventional doses of neuroleptics. The schizophrenics receiving low doses (n = 6) had preponderant negative symptoms. Mean D2 receptor occupancy was 24 ± 20%. Despite this weak central D2 receptor blockade, a significant decrease in negative symptoms was observed, a result consistent with the hypothesis of a disinhibitory action of some neuroleptics administered in low doses. The patients treated with conventional doses (n = 9) had mixed positive and negative symptoms, and the mean D2 receptor occupancy was 54 ± 13%. Significant decreases in positive symptoms, but also in negative symptoms, were obtained with this treatment. Before treatment, there was no significant difference in the striatal D2 receptor density/affinity index between: 1) patients and controls, 2) negative and mixed schizophrenics, and 3) the subsequent responder and non-responder patients. In addition, the D2 dopamine receptor occupancy by neuroleptics did not significantly differ in responder or nonresponder patients, suggesting that the central D2 dopamine receptor blockade is a necessary, but insufficient condition to account for the antipsychotic effect of neuroleptics.

Implications of Positron Emission Tomography Research for the Investigation of the Actions of Antipsychotic Drugs

1993 ◽  
Vol 163 (S22) ◽  
pp. 25-30 ◽  
Author(s):  
Stephen J. List ◽  
John M. Cleghorn
Keyword(s):  
Positron Emission Tomography ◽  
Blood Flow ◽  
Dopamine Receptor ◽  
Receptor Binding ◽  
Brain Metabolism ◽  
Emission Tomography ◽  
Regional Brain ◽  
Positron Emission ◽  
Dopamine Receptor Binding ◽  
The Relationship

Positron emission tomography studies of regional brain metabolic activity, cerebral blood flow and D2 dopamine receptor binding in schizophrenics and controls are reviewed. Methodological influences on the validity of the data generated by these technologies include problems with measurement as well as clinical and anatomical heterogeneity. Work in these fields to date, however, has produced strong support for the role of D2 dopamine receptor blockade in antipsychotic efficacy. Neuroleptic-induced changes in regional brain metabolism over time have also been observed; however, the relationship between such actions and symptomatic change needs to be further clarified. Future studies on time-course of neuroleptic-associated changes in regional brain metabolism, blood flow and dopamine receptor binding in schizophrenics have the potential to provide greater insight into the relationship of these actions to symptomatic changes and drug-induced side-effects.

Usefulness of positron emission tomography for differentiating gliomas according to the 2016 World Health Organization classification of tumors of the central nervous system

2020 ◽  
Vol 133 (4) ◽  
pp. 1010-1019 ◽  
Author(s):  
Hiroaki Takei ◽  
Jun Shinoda ◽  
Soko Ikuta ◽  
Takashi Maruyama ◽  
Yoshihiro Muragaki ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Pet Imaging ◽  
Who Classification ◽  
Standardized Uptake Value ◽  
Emission Tomography ◽  
World Health ◽  
Pet Tracers ◽  
Positron Emission ◽  
Significant Difference ◽  
The Mean

OBJECTIVEPositron emission tomography (PET) is important in the noninvasive diagnostic imaging of gliomas. There are many PET studies on glioma diagnosis based on the 2007 WHO classification; however, there are no studies on glioma diagnosis using the new classification (the 2016 WHO classification). Here, the authors investigated the relationship between uptake of 11C-methionine (MET), 11C-choline (CHO), and 18F-fluorodeoxyglucose (FDG) on PET imaging and isocitrate dehydrogenase (IDH) status (wild-type [IDH-wt] or mutant [IDH-mut]) in astrocytic and oligodendroglial tumors according to the 2016 WHO classification.METHODSIn total, 105 patients with newly diagnosed cerebral gliomas (6 diffuse astrocytomas [DAs] with IDH-wt, 6 DAs with IDH-mut, 7 anaplastic astrocytomas [AAs] with IDH-wt, 24 AAs with IDH-mut, 26 glioblastomas [GBMs] with IDH-wt, 5 GBMs with IDH-mut, 19 oligodendrogliomas [ODs], and 12 anaplastic oligodendrogliomas [AOs]) were included. All OD and AO patients had both IDH-mut and 1p/19q codeletion. The maximum standardized uptake value (SUV) of the tumor/mean SUV of normal cortex (T/N) ratios for MET, CHO, and FDG were calculated, and the mean T/N ratios of DA, AA, and GBM with IDH-wt and IDH-mut were compared. The diagnostic accuracy for distinguishing gliomas with IDH-wt from those with IDH-mut was assessed using receiver operating characteristic (ROC) curve analysis of the mean T/N ratios for the 3 PET tracers.RESULTSThere were significant differences in the mean T/N ratios for all 3 PET tracers between the IDH-wt and IDH-mut groups of all histological classifications (p < 0.001). Among the 27 gliomas with mean T/N ratios higher than the cutoff values for all 3 PET tracers, 23 (85.2%) were classified into the IDH-wt group using ROC analysis. In DA, there were no significant differences in the T/N ratios for MET, CHO, and FDG between the IDH-wt and IDH-mut groups. In AA, the mean T/N ratios of all 3 PET tracers in the IDH-wt group were significantly higher than those in the IDH-mut group (p < 0.01). In GBM, the mean T/N ratio in the IDH-wt group was significantly higher than that in the IDH-mut group for both MET (p = 0.034) and CHO (p = 0.01). However, there was no significant difference in the ratio for FDG.CONCLUSIONSPET imaging using MET, CHO, and FDG was suggested to be informative for preoperatively differentiating gliomas according to the 2016 WHO classification, particularly for differentiating IDH-wt and IDH-mut tumors.

Evaluation of individual skeletal muscle activity by glucose uptake during pedaling exercise at different workloads using positron emission tomography

2009 ◽  
Vol 107 (2) ◽  
pp. 599-604 ◽  
Author(s):  
Yuichi Gondoh ◽  
Manabu Tashiro ◽  
Masatoshi Itoh ◽  
Mohammad M. Masud ◽  
Hiroomi Sensui ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Positron Emission Tomography ◽  
Glucose Uptake ◽  
Muscle Activity ◽  
Rectus Femoris ◽  
Emission Tomography ◽  
Whole Body ◽  
Control Subjects ◽  
Positron Emission ◽  
Iliacus Muscle

Skeletal muscle glucose uptake closely reflects muscle activity at exercise intensity levels <55% of maximal oxygen consumption (V̇o2max). Our purpose was to evaluate individual skeletal muscle activity from glucose uptake in humans during pedaling exercise at different workloads by using [18F]fluorodeoxyglucose (FDG) and positron emission tomography (PET). Twenty healthy male subjects were divided into two groups (7 exercise subjects and 13 control subjects). Exercise subjects were studied during 35 min of pedaling exercise at 40 and 55% V̇o2max exercise intensities. FDG was injected 10 min after the start of exercise or after 20 min of rest. PET scanning of the whole body was conducted after completion of the exercise or rest period. In exercise subjects, mean FDG uptake [standardized uptake ratio (SUR)] of the iliacus muscle and muscles of the anterior part of the thigh was significantly greater than uptake in muscles of control subjects. At 55% V̇o2max exercise, SURs of the iliacus muscle and thigh muscles, except for the rectus femoris, increased significantly compared with SURs at 40% V̇o2max exercise. Our results are the first to clarify that the iliacus muscle, as well as the muscles of the anterior thigh, is the prime muscle used during pedaling exercise. In addition, the iliacus muscle and all muscles in the thigh, except for the rectus femoris, contribute when the workload of the pedaling exercise increases from 40 to 55% V̇o2max.

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