Histamine H|3 activation depresses cardiac function in experimental sepsis
Bibliographic record
Abstract
In the heart, histamine H$\\sb3$ receptors may function as inhibitory heteroreceptors that downregulate norepinephine exocytosis in pathological conditions associated with enhanced sympathetic neural activity. In sepsis, there is intense adrenergic stimulation as cardiovascular collapse develops over the course of the illness. Intense adrenergic stimulation may lead to histamine release and activation of cardiac H$\\sb3$ receptors. Inhibition of cardiac adrenergic responses could lead to a relative decrease in cardiac output contributing to cardiovascular collapse in a gram-negative sepsis. In the present study, it was hypothesized that H$\\sb3$ receptor blockade might improve cardiovascular function in sepsis. In a canine model of E. coli sepsis, it was observed that after 4 hrs of bacteremia, the H$\\sb3$ receptor blocker (thioperamide maleate or clobenproprit) caused an increase in cardiac output (3.6 to 5.3 L/min; p $<$ 0.05) and blood pressure (mean 76 to 96 mmHg, p $<$ 0.05) compared with pretreatment values. In the cardiac mechanics study, H$\\sb3$ receptor blockade improved left ventricular contractility in sepsis. Plasma histamine concentrations increased in the H$\\sb3$ blocker/sepsis group as compared with a nonsepsis time control group. In a ventricular trabecular preparation, H$\\sb3$ receptor blockade caused an increase in the adrenergic response in the presence of septic plasma. The present study shows that activation of H$\\sb3$ receptors may contribute to cardiovascular collapse in sepsis.
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 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".