Effect of hindlimb unloading on sympathetic vasoconstriction in resting and contracting skeletal muscle (1165.3)
Bibliographic record
Abstract
We hypothesized that hindlimb unloading (HU) would increase sympathetic vasoconstrictor responsiveness and diminish nitric oxide (NO) mediated inhibition of sympathetic vasoconstriction in resting and contracting skeletal muscle. Sprague‐Dawley rats (n=21) were randomized to sedentary time‐control (S; n = 9) or HU (n = 12) groups for 21d. Rats were anesthetized and instrumented for stimulation of the lumbar sympathetic chain and measurement of femoral vascular conductance (FVC). Sympathetic stimulations were delivered at 2Hz and 5Hz at rest and during contraction of the triceps surae muscles at 60% of maximal contractile force before and after NO synthase blockade (L‐NAME; 5mg·kg ‐1 IV). The percentage decrease in FVC in response to sympathetic stimulation was not different (P > 0.05) between groups at rest (HU: 2Hz: ‐29 ± 10%; 5Hz: ‐50 ± 12%; S: 2Hz: ‐26 ± 10%, 5Hz: ‐44 ± 8%) and during contraction (HU: 2Hz: ‐9 ± 4%; 5Hz: ‐22 ± 7%; S: 2Hz: ‐7 ± 5%; 5Hz:‐18 ± 7%). In the presence of L‐NAME the vasoconstrictor response was not different (P > 0.05) between groups at rest (HU: 2Hz: ‐43 ± 7%; 5Hz: ‐63 ± 10%; S: 2Hz: ‐42 ± 8%; 5Hz: ‐57 ± 6%) and during contraction (HU: 2Hz: ‐12 ± 3%; 5Hz: ‐24 ± 6%; S: 2Hz: ‐12 ± 4%; 5Hz: ‐28 ± 8%). We conclude that HU does not alter sympathetic vasoconstrictor responsiveness or NO mediated inhibition of sympathetic vasoconstriction in resting and contracting skeletal muscle. Grant Funding Source : Supported by NSERC, Canada.
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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) | 0.001 | 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) | 0.003 | 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".