Leptin-Induced Endothelium-Independent Vasoconstriction in Thoracic Aorta and Pulmonary Artery of Spontaneously Hypertensive Rats: Role of Calcium Channels and Stores
Bibliographic record
Abstract
Decreased leptin-induced endothelium-dependent vasodilation has been reported in spontaneously hypertensive rats (SHR). Here, we report leptin-induced vasoconstriction in endothelium-denuded pulmonary artery and thoracic aorta from SHR and sought to characterize calcium handling underlying these mechanisms. Vasoreactivity to leptin was evaluated on pulmonary artery and thoracic aorta rings from 18 weeks old male SHR with or without calcium free medium, caffeine + thapsigargin + carbonyl cyanide-4-trifluoromethoxyphenylhydrazone emptying intracellular calcium stores, nifedipine a voltage-gated calcium channel inhibitor, SKF-96365 a transient receptor potential cation channels (TRPC) inhibitor, wortmaninn, a phosphatidylinositide 3-kinases (PI3K) inhibitor, or PD98059 a mitogen-activated protein kinase kinase (MAPKK) inhibitor. Calcium imaging was performed on cultured vascular smooth muscle cells incubated with leptin in presence or not of wortmaninn or PD98059. Leptin induced vasoconstriction in denuded pulmonary artery and thoracic aorta from SHR. Response was abolished when intra- or extracellular calcium stores were emptied, after blocking TRPC or voltage-dependent calcium channels or when using MAPKK or PI3K inhibitors. In vascular smooth muscle cells, leptin increased intracellular calcium. This rise was higher in SHR and abolished by MAPKK or PI3K inhibitors. TRPC6 gene expression was upregulated in arteries from SHR. Leptin-induced vasoconstriction in denuded arteries of SHR requires intracellular stores and is TRPC- and voltage-gated calcium channels dependent. Intracellular calcium increase is more pronounced in spontaneously hypertensive rats.
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) | 0.000 | 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 | 0.001 |
| 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".