The effect of aging on vasomotion responses to varying rates of local heating.
Bibliographic record
Abstract
We compared the cutaneous microvascular vasomotion responses of 8 young (23 ± 1 yr) and 8 older (68 ± 2 yr) adults in the forearm and leg using laser‐Doppler fluxmetry (LDF) and wavelet analysis to investigate endothelial, neurogenic, and myogenic activity. We measured cutaneous microvascular responses at uncontrolled basal temperature (27 ± 2.2 °C), controlled basal temperature (33 °C), and initial vasodilation (onset of heating), and sustained vasodilation, at 42 and 44 °C, in response to both a slow (0.1 °C · 10 s‐1) and a fast (0.5 °C · 10 s‐1) local heating protocol. At baseline (no heating), there were no differences between the groups (all P > 0.05). At a controlled local temperature of 33 °C (thermoneutral), neurogenic activity was higher in the leg of the young compared to the older group ( P = 0.04). Following the initiation of the heating protocols, the young participants responded with higher neurogenic activity in the forearm compared to the older group during fast local heating ( P = 0.03), but not in response to slow local heating ( P > 0.05). In the leg, the young group had higher endothelial nitric oxideindependent activity compared to the older group ( P = 0.01) for both heating protocols. The young group also had an increase in endothelial nitric oxide‐dependent activity during the slow protocol ( P < 0.001), while the older cohort experienced increases in neurogenic ( P = 0.02) and myogenic ( P = 0.04) activity. Following 35 min at 42 °C, neurogenic activity was significantly increased in the leg of the older group compared to the young group during the slow heating protocol ( P = 0.02). Furthermore, after increasing local temperature from 42 to 44 °C, the older adults had higher endothelial nitric oxide‐independent activity ( P = 0.04) in the forearm of the fast protocol while the young subjects had higher neurogenic activity ( P = 0.04). Neurogenic activity in the leg of the older group was increased ( P = 0.02) during the fast protocol at 44 °C. These results suggest that regional differences in the response to local heating persist with age and that the primary mechanisms responsible for vasodilation caused by local heating are diminished with age; however, overall vasodilation is offset by the other mechanisms. Moreover, our results suggest that as we age the reliance on endothelial activity shifts from endothelial nitric oxide‐dependent to endothelial nitric oxide‐independent mechanisms. These data suggest that the cutaneous bioavailability of nitric oxide is diminished with age. Support or Funding Information Ball State University SPA Fellows Stipend This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .
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 | 0.001 | 0.001 |
| 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) | 0.001 | 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".