The Blue Light‐Responsive Lateral Pathway of the Retinohypothalamic Tract Promotes Endocannabinoid‐Driven Modulation of Orexin Neurons
Bibliographic record
Abstract
Circadian light influences brain functions in mammals. Photic non-image-forming stimuli are transduced into electrochemical signals by photosensitive retinal ganglion cells containing melanopsin, a selective blue light-responsive photopigment. The hypothalamus receives light-related information via the retinohypothalamic tract (RHT). Here, we demonstrate that, in the mouse, a lateral branch of the RHT (l-RHT) projects monosynaptically to orexin-A (OX-A) neurons in the perifornical hypothalamic area (PFH). Intravitreal injection of the anterograde tracer cholera toxin-β (CTβ) filled most of the vesicular glutamate transporter (VGluT1)/cannabinoid receptor 1 (CB1R)-positive retinal-derived inputs projecting to the OX-A neurons. Monocular injection of Fluo4-Dextran, a fluorimetric sensor of calcium mobilization, yielded fast labeling of these inputs 10 min after eye exposure to blue light, concomitantly with the enhancement of hypothalamic 2-arachidonoylglycerol (2-AG) levels, and inhibition of OX-A neuronal firing, an effect prevented by in vivo administration of the CB1R antagonist AM251. Our findings provide anatomical and functional evidence of a selective retino-hypothalamic network responsive to blue light, whose control should be suitable for therapies to counteract sleep disorders, seasonal affective disorder, or even conditions like narcolepsy or anxiety.
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) | 0.000 | 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) | 0.001 | 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 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".