Vacuolar H+-ATPase and Na+/K+-ATPase energize Na+ uptake mechanisms in the nuchal organ of the hyperregulating freshwater crustacean <i>Daphnia magna</i>
Bibliographic record
Abstract
The nuchal organ of the embryos and neonates of the cladoceran, Daphnia magna, has been shown to be a site of Na+ influx and H+, NH4+ and Cl- efflux. This study combines the scanning ion-selective electrode technique with application of inhibitors of specific transporters to assess the mechanisms of Na+ transport across the nuchal organ. Na+ influx across the nuchal organ was inhibited both by inhibitors of the Na+/K+-ATPase (ouabain, bufalin) and by inhibitors of the vacuolar H+-ATPase (bafilomycin, N-ethylmaleimde, 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole, KM91104, S-nitrosoglutathione). Na+ influx was unaffected by the epithelial Na+ channel blocker benzamil, but was sensitive to ethylisopropyl amiloride and elevated external ammonium concentrations, consistent with roles for Na+/H+ and Na+/NH4+ exchangers in the apical membrane but not Na+ channels. Transport across the basolateral membrane into the haemolymph is proposed to involve the Na+/K+-ATPase and a thiazide-sensitive Na+/Cl- cotransporter.
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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) | 0.000 | 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) | 0.000 | 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".