Repeated daily injections and osmotic pump infusion of isoproterenol cause similar increases in cardiac mass but have different effects on blood pressure
Bibliographic record
Abstract
We found in mice that repeated single daily subcutaneous (s.c.) isoproterenol (ISO) injections, like constant infusions using osmotic minipumps, caused increased biventricular mass or weight relative to body weight (VW/BW). We found that 5 (1/d) s.c. injections of 2, 10, or 20 microg/g body weight caused equivalent VW/BW increases as compared with 5-d infusions at 20 microg/(g.d)). While it is often presumed that ISO elicits hypertrophy by a direct effect on the myocytes, growth may also be secondary to systemic hemodynamic effects. The 2 modes of ISO administration had different effects on mean arterial blood pressure (MABP) and heart rate. Using telemetry we observed that single injections of ISO (0, 0.5, 2, and 10 microg/g) were associated with hypotension and tachycardia with a duration but not a magnitude that was dose dependent. MABP dropped rapidly to 60 mm Hg for more than 2 h at the highest dose. Constant s.c. infusion of ISO at 20 microg/(g.d) initially lowered MABP to about 70 mm Hg for 24 h. At 48 h MABP was normal, but rose 10 mm Hg higher than baseline by day 5. Thus, different routes of administration of ISO that cause comparable increases in VW/BW had different effects on MABP. Thus when evaluating mouse models of ISO-induced cardiac hypertrophy, both repeated daily injections or infusions can cause similar increases in VW/BW, but the daily doses that are required are not the same. Furthermore, these different routes of administration have different hemodynamic sequelae and could potentially evoke different cardiac phenotypes.
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 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.003 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
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".