Contribution of nitric oxide synthase to cutaneous vasodilatation and sweating in men of black‐African and Caucasian descent during exercise in the heat
Bibliographic record
Abstract
New Findings What is the central question of this study? Nitric oxide modulates cutaneous vasodilatation and sweating during exercise‐induced heat stress in young men. However, it remains uncertain whether these effects are reduced in black‐African descendants, who commonly demonstrate reduced nitric oxide bioavailability. Therefore, we assessed whether black‐African descendants display reduced nitric oxide‐dependent cutaneous vasodilatation and sweating compared with Caucasians in these conditions. What is the main finding and its importance? Nitric oxide‐dependent cutaneous vasodilatation and sweating were similar between groups, indicating that reduced nitric oxide bioavailability in black‐African descendants does not attenuate these heat‐loss responses during an exercise‐induced heat stress. Abstract Men of black‐African descent are at an increased risk of heat‐related illness relative to their Caucasian counterparts. This might be attributable, in part, to reduced cutaneous nitric oxide (NO) bioavailability in this population, which might alter local cutaneous vasodilatation and sweating. To evaluate this, we compared these heat‐loss responses in young men (18–30 years of age) of black‐African ( n = 10) and Caucasian ( n = 10) descent during rest, exercise and recovery in the heat. Participants were matched for physical characteristics and fitness, and they were all born and raised in the same temperate environment (i.e. Canada; second generation and higher). Both groups rested for 10 min and then performed 50 min of moderate‐intensity exercise at 200 W m −2 , followed by 30 min of recovery in hot, dry heat (35°C, 20% relative humidity). Local cutaneous vascular conductance (CVC %max ) and sweat rate (SR) were measured at two forearm skin sites treated with either lactated Ringer solution (control) or 10 m m N G ‐nitro‐ l ‐arginine methyl ester ( l ‐NAME, a nitric oxide (NO) synthase inhibitor). l ‐NAME significantly reduced CVC %max throughout rest, exercise and recovery in both groups (both P < 0.001). However, there were no significant main effects for the contribution of NO to CVC %max between groups (all P > 0.500). l ‐NAME significantly reduced local SR in both groups (both P < 0.050). The contribution of NO to SR was similar between groups such that l ‐NAME reduced SR relative to control at 40 and 50 min into exercise (both P < 0.05). We demonstrate that ethnicity per se does not influence NO‐dependent cutaneous vasodilatation and sweating in healthy young men of black‐African and Caucasian descent during exercise in dry heat.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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 teacher head, 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".