ULTRA-LOW DOSE OF NALOXONE POTENTIATES ANALGESIC EFFECT INDUCED BY ELECTROACUPUNCTURE, BUT DOES NOT AFFECT ITS SUPPRESSIVE EFFECT ON MORPHINE WITHDRAWAL IN RATS
Bibliographic record
Abstract
Aim: Naloxone ( NX) is a well-known opioid receptor antagonist that blocks opioid analgesia. However there was an unexpected and paradoxical observation that administration of extremely low doses of NX enhanced, rather than attenuated, the analgesic effects produced by small doses of morphine or other opioid agonists. The aim of this study was to determine whether ultra-low dose of NX could increase the efficacy of EA-induced analgesia and the suppression of morphine withdrawal in rats. Methods: (1 ) adult male Sprague Dawley ( SD) rats were randomly divided into seven groups of 8 -10 each, receiving normal saline (NS) , NX 10 ng/kg, 2 Hz EA, 100 Hz EA, 2 Hz or 100 Hz EA plus NX 10 ng/kg, or no treatment as blank control. Nociceptive threshold was measured by radiant heat-induced tail flick latency (TFL). (2) Adult male SD rats were made dependent on morphine by multiple injections of increasing doses of morphine for 5 days. The rats were randomly divided into six groups of 8 - 10 each, receiving NS, NX 10 ng/kg, 2 Hz EA, 100 Hz EA, and 2 Hz or 100 Hz EA plus NX 10 ng/kg, respectively. They were given EA for 30 min 6 h after the last injection of morphine, followed by intraperitoneal (i. p. ) administration of naloxone (1 mg/kg). Body weight loss (g) was measured before and 60 min after the NX injection. Results: (1) NX 10 ng/kg did not significantly influence the basal level of TFL, but significantly potentiate the analgesic effect induced by 2 Hz EA, with the effect lasting as long as 120 min. The analgesic effect produced by 100 Hz EA was not affected. (2) NX 10 ng/kg did not significantly influence NX-induced body weight loss in morphine-dependent rat. 2 Hz or 100 Hz EA for 30 min significantly reduced the body weight loss (P 0. 01). The efficacy of EA was not affected by NX 10 ng/ kg. Conclusion: (1 ) Ultra-low dose of NX selectively increases the analgesic effect induced by 2 Hz EA in the rat, which may have potential clinical impact. (2) It did not affect the efficacy of EA in suppressing body weight loss in morphine withdrawal rats.
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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 | 0.000 |
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".