Stimulation of Amylase Release by Orexin is Mediated by Orexin 2 Receptor in AR42J Cells
Bibliographic record
Abstract
INTRODUCTION AND AIMS: Orexins have been demonstrated to have mainly central physiological functions, including regulation of food and water intake, sleep, and arousal. However, little is known about their direct peripheral effects, if any. As a first step toward understanding the role of Orexin in non-neuronal tissues or cells, we initiated studies to examine expression of Orexin receptors (OXR) in an established pancreatic tumor cell line AR42J. Secondly, we wanted to determine whether Orexins, in various molecular forms, are active to stimulate any known pancreatic cell functions in AR42J cells. METHODOLOGY: Reverse transcription-PCR analysis was performed to identify the presence of specific Orexin receptor subtypes. Intracellular calcium mobilization and cAMP levels were measured following stimulation by Orexin A and B peptides, their respective C-terminal decapeptide fragments, and hypocretin-2-gly (glycine-extended Orexin B). Release of alpha-amylase was measured in conditioned media after acute stimulation with the set of Orexin peptides for 30 minutes. Cell proliferation was determined by H-thymidine incorporation after 24 hours following treatment with Orexins under serum-free condition. RESULTS: RT-PCR and sequencing results showed that Orexin receptor subtype 2 (OX2R) was the main form expressed in AR42J cells. Orexins stimulated dose-dependent increases in intracellular calcium mobilization with EC50 0.05 nM for Orexin A and 0.1 nM for Orexin B but were unable to stimulate any significant cAMP accumulation or DNA synthesis even at micromolar concentrations. Both Orexin-A and -B, but not hypocretin-2-gly, also stimulated dose-dependent increases in amylase release in the AR42J cells. Orexin-A and -B carboxyl-terminal decapeptides elicited significant but much lower calcium and amylase responses. CONCLUSION: Our data demonstrate that OX2R mediates Ca -dependent amylase release in AR42J cells, suggesting that Orexins may have secretory functions in pancreatic tumor cells.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 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) | 0.004 | 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; both teacher heads agree on what is shown here.
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".