Proteinase activated receptor‐2 (PAR‐2) inhibits spontaneous activity in rat colon via adrenergic nerves
Bibliographic record
Abstract
Rat colonic smooth muscle shows spontaneous contractile activity which is generated by pacemaker cells. We have investigated whether this spontaneous activity can be modulated by proteinase activated receptor-2 (PAR-2), a G-protein coupled receptor activated by proteolytic cleavage. Strips of rat colon longitudinal muscle were suspended in organ baths and increasing concentrations of the PAR-2 mimetic peptide f-LIGRL were applied. f-LIGRL induced concentration-dependent inhibition of spontaneous contractile activity of rat colon that was sensitive to apamin, an inhibitor of small conductance Ca2+-activated potassium channels. Tetrodotoxin, an inhibitor of neurotransmission, blocked the effects of f-LIGRL as did phentolamine, an α-adrenoceptor antagonist. Propanolol, a β-adrenoceptor antagonist, had only small inhibitory effect on f-LIGRL-evoked responses. The adrenergic neuronal blocker guanethidine reduced responses to f-LIGRL supporting our conclusion that PAR-2 activation inhibits spontaneous contractile activity in the rat colon by releasing noradrenaline from adrenergic neurons to act on α-adrenoceptors on pacemaker cells. Supported by NSERC
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 | 0.001 |
| 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".