Skeletal muscle microvascular hemodynamic responses during hyperinsulinemic-euglycemic clamp in a Zucker Diabetic Sprague Dawley rat model of type 2 diabetes
Bibliographic record
Abstract
Objective We sought to measure skeletal muscle microvascular hemodynamic responses in Sprague Dawley (SD) and Zucker Diabetic Sprague Dawley (ZDSD) rat model of type 2 diabetes (T2D) at rest and during a hyperinsulinemic-euglycemic clamp under resting conditions and during acute changes in local tissue oxygen concentration [(O2)]. Methods Male SD and ZDSD rats were fed a high-fat diet, transitioned to a high-fat high-sugar diet from 16–19 weeks old to induce T2D in the ZDSD strain, then returned to the high-fat diet until intravital video microscopy (IVVM). At 27 weeks of age animals were fasted overnight, and on the morning of the IVVM experiment animals were anaesthetized, instrumented, and mechanically ventilated. The extensor digitorum longus muscle was blunt dissected, isolated, and reflected over a glass coverslip or a gas exchange chamber (GEC) fitted in the stage of an inverted microscope. Microvascular hemodynamic responses were recorded during baseline and hyperinsulinemic-euglycemic clamp without perturbation (Protocol 1) and during sequential changes in GEC [O2] (7%-12%-2%-7%) (Protocol 2). Results In protocol 1, SD rats had a significant increase in red blood cell (RBC) velocity, RBC supply rate (SR), and RBC oxygen saturation (SO2) between baseline and euglycemia. However, ZDSD animals had no significant difference in hemodynamic responses and RBC SO2 between baseline and during hyperinsulinemic-euglycemic clamp. RBC SO2 was significantly higher in ZDSD than SD rats at baseline. In protocol 2, ZDSD rats had significantly higher RBC SO2 than their SD counterparts at 7% and 2% [O2]. RBC velocity, SR and capillary hematocrit showed no change from 7% in response to increased or decreased [O2] in either animal group. ZDSD rats had a significant increase between baseline and clamp in RBC SR at 12% as well as at 2% GEC [O2]. Conclusion SD rats had a robust increase in capillary hemodynamics during hyperinsulinemic-euglycemic clamp whereas the capillary hemodynamics in ZDSD rats did not significantly change. Additionally, SD and ZDSD rats lacked expected hemodynamic responses in response to local [O2] changes during baseline and hyperinsulinemic-euglycemic clamp. This finding suggests that hyperglycemia in T2D and high-fat feeding alter microvascular hemodynamic responses to acute changes in muscle [O2].
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 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) | 0.001 | 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".