Myogenic Constriction is not Dependent on Endothelium in Arcuate and Mesenteric Arteries of Normotensive and Hypertensive Rats
Notice bibliographique
Résumé
Background Myogenic response (MR) is defined as contraction of small arteries in response to increased intraluminal pressure. Impaired MR is associated with hypertension and Chronic Kidney Disease (CKD). MR has been shown to be regulated by endothelium (ENDO) through production of vasodilators and vasoconstrictors which are differentially produced in different vascular beds. Despite this evidence, there are conflicting literature reports on the dependency of MR on ENDO. This dependency was never investigated in arcuate and mesenteric arteries of normotensive and hypertensive rats. We hypothesized that MR is dependent on ENDO and removing ENDO abolishes MR in arcuate and mesenteric arteries of Wistar Kyoto (WKY, normotensive) and Spontaneously Hypertensive Rats (SHR, hypertensive) rats. Methods Arteries were mounted in a pressure myograph chamber (PMC) filled with oxygenated Hank Balance Salt Solution (HBSS) to create a blind sac and allowed 30 min to equilibrate. Intact vascular smooth muscle cell (VSMC) and ENDO layers were evaluated by addition of a pre‐determined median effective dose of phenylephrine (0.2 μM) and carbachol (10 μM) respectively. MR was measured in response to step‐wise increases in intraluminal pressure from 80 to 180 mmHg (20 mmHg increments, 5 min each) (E‐intact MR). The arteries were then transferred into a petri dish containing human hair and moved through the length of the hair 5 times to remove ENDO (Osol et al., 1989). The vessels were re‐mounted, HBSS was flushed through the arteries for 5 mins, and blind sac was re‐created. Phenylephrine and carbachol were added and MR was re‐measured (E‐removed MR). Physical absence of ENDO was further assessed by Scanning Electron Microscopy (SEM). Results All arteries contracted to phenylephrine before and after ENDO removal and did not relax significantly to carbachol after ENDO removal. SEM micrographs showed complete physical absence of the ENDO. MC in E‐removed vessels were not significantly different from MC in E‐intact in mesenteric and arcuate arteries of WKY and SHR rats. Conclusions Our study validated an ENDO removal method that was described by Osol, et al . in 1989. Additionally, MR was shown to be independent of ENDO in mesenteric and arcuate arteries of WKY and SHR rats. Support or Funding Information This work was supported by Canadian Institutes of Health Research grants to Dr. Jeffrey G. Dickhout (PJT148499). This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».