Effect of acute antipsychotic administration on dopamine synthesis in rodents and human subjects using 6‐[<sup>18</sup>F]‐L‐<i>m</i>‐tyrosine
Bibliographic record
Abstract
Clinical effects of antipsychotic drugs are thought to be mediated primarily through antagonism of the dopamine D2 receptors. Recent studies have demonstrated increased aromatic decarboxylase activity following acute administration of dopamine D2 receptor antagonists both in vivo and ex vivo. However, this effect has never been demonstrated in human subjects. We studied the effect of acute antipsychotic administration on dopamine synthesis in rodents and healthy human subjects using 6-[18F]-L-m-tyrosine. In rats, we studied the effect of a single subcutaneous injection of haloperidol and risperidone on dopamine synthesis using 6-[18F]-L-m-tyrosine. In our human study, six healthy volunteers underwent two 6-[18F]-L-m-tyrosine PET scans, before and after 3 mg risperidone to measure the rate of accumulation of radioactivity in the striatum as an index of dopamine synthesis. The striatal/cerebellar radioactivity count ratio and the ratio of dopamine metabolites to dopamine concentration was significantly higher in all rodent treatment groups compared to controls. In the PET study we found no significant change in the rate of uptake in the striatum. Our results suggest that 6-[18F]-L-m-tyrosine PET may not be a useful tool in the study of the effect of antipsychotics on dopamine synthesis in human subjects.
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.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. 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.
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) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| 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)
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.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".