In vitro Biochemical Characterization and Autoradiographic Distribution of <sup>3</sup> H-Thyrotropin-Releasing Hormone Binding Sites in Rat Brain Sections
Bibliographic record
Abstract
In the present study, we describe the biochemical characteristics and the autoradiographic distribution of thyrotropin-releasing hormone (TRH) receptors in the rat central nervous system (CNS) after in vitro incubation of brain slices with 3H-TRH. Scatchard analysis showed that, in the range of concentrations tested (0.7-35 nM), 3H-TRH bound to a single-class of receptors with a dissociation constant of 6 nM and a number of binding sites of 20 fmol/mg protein. Increasing concentrations of unlabeled TRH produced a dose-dependent inhibition of 3H-TRH binding. The only analogue as potent as TRH to displace 3H-TRH binding was 3-Me-TRH, whereas 1-Me-TRH or TRH-free acid as well as pGlu-His, pGlu-Pro-NH2 or His-Pro-diketopiperazine were ineffective. Neither Luteinizing hormone-releasing hormone (LHRH), neurotensin, somatostatin, D-Ala-Met-enkephalin nor VIP showed any significant affinity for TRH binding sites. Autoradiograms obtained by apposition of LKB 3H-Ultrofilm showed that the highest concentrations of 3H-TRH binding sites were found in the ventral dentate gyrus of the hippocampal formation, the lateral amygdaloid nucleus, the nucleus accumbens, and the thalamic paraventricular nucleus. The biochemical characterization of 3H-TRH binding in brain sections is in good agreement with previous reports on membrane preparations and the autoradiographic localization of the binding sites provides anatomical support for the effects of TRH in the CNS.
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 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 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
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 source (direct Gemma or distilled Codex), 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".