A Positron Emission Tomography Study of Quetiapine in Schizophrenia: A Preliminary Finding of an Antipsychotic Effect With Only Transiently High Dopamine D2 Receptor Occupancy
Why is this work in the frame?
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Full frame distilled prediction
Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
- Candidate categories
- Meta-epidemiology (narrow)
- Consensus categories
- none
- Domain
- Candidate signal: noneConsensus signal: none
- Study design
- Candidate signal: ObservationalConsensus signal: Observational
- Genre
- Candidate signal: EmpiricalConsensus signal: Empirical
- Teacher disagreement score
- 0.255
- Threshold uncertainty score
- 1.000
- Validation status
machine_predicted_unvalidated·codex-gemma-dda1882f352a
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
- Teacher spread
- 0.264 · how far apart the two teachers sit on this one work
- Validation status
score_only:v0-immature-baseline· verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it
Abstract
BACKGROUND: Quetiapine is a new atypical antipsychotic medication. As such, relatively little has been published regarding its in vivo effects at the dopamine type 2 (D2) and serotonin type 2a (5-HT2a) receptor systems. The following study was undertaken to explore these effects across the clinical dose range and relate this information to its clinical profile. METHODS: Twelve patients with schizophrenia were randomly assigned to doses of 150 to 600 mg/d (n=3, at 150, 300, 450, and 600 mg/d) of quetiapine. After 3 weeks of treatment, D2 and 5-HT2a occupancy were measured using positron emission tomography (PET) imaging, 12 to 14 hours after the last dose. Clinical efficacy and adverse effect ratings were obtained at baseline, at the time of PET scanning, and at 12 weeks. Two additional patients were included to examine the effects of the drug 2 to 3 hours after last dose. RESULTS: Quetiapine was an effective antipsychotic and improved the extrapyramidal symptoms and prolactin level elevation noted at baseline. It achieved these results with minimal (0%-27%) D2 occupancy 12 hours after the last dose. Study of the additional subjects revealed that quetiapine does give rise to transiently high (58%-64%) D2 occupancy 2 to 3 hours after a single dose that then decreases to minimal levels in 12 hours. CONCLUSIONS: Quetiapine shows a transiently high D2 occupancy, which decreases to very low levels by the end of the dosing interval. Quetiapine's low D2 occupancy can explain its freedom from extrapyramidal symptoms and prolactin level elevation. The data suggest that transient D2 occupancy may be sufficient for its antipsychotic effect. Future studies controlling for nonpharmacological effects as well as activities on other receptors will be necessary to confirm this suggestion.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
The record
- Venue
- Archives of General Psychiatry
- Topic
- Schizophrenia research and treatment
- Field
- Medicine
- Canadian institutions
- University of Toronto
- Funders
- not available
- Keywords
- QuetiapineExtrapyramidal symptomsDopamine receptor D2Quetiapine FumarateMedicineAtypical antipsychoticAntipsychoticAdverse effectSchizophrenia (object-oriented programming)Positron emission tomographyInternal medicinePsychologyPharmacologyDopamineNuclear medicinePsychiatry
- Has abstract in OpenAlex
- yes