Searching across hundreds of databases
Acid–base transport in the vascular wall remains incompletely understood. Here, we investigated (a) implications of Na(+)/H(+) exchanger NHE1 knockout for vascular smooth muscle (VSMC) and endothelial cell (EC) pH(i) regulation, mesenteric artery morphology, vasomotor function and blood pressure regulation, and (b) consequences of sustained EC and VSMC acidification for vasomotor function. Na(+)/H(+) exchange activity was abolished in VSMCs and ECs from NHE1 knockout mice, but with CO(2)/HCO(3)(−) present, steady-state pH(i) was unaffected. Active tension was 30% smaller in arteries from NHE1 knockout than wild-type mice, and media thickness equally reduced. Number of VSMCs per unit artery length was unchanged whereas volume and cross-sectional area of individual VSMCs were reduced. Media stress, force production per VSMC cross-sectional area and VSMC Ca(2+) responses were unaffected. Blood pressure was 25 mmHg lower in NHE1 knockout than wild-type mice. Omission of CO(2)/HCO(3)(−) caused VSMCs and ECs to acidify substantially more in NHE1 knockout (0.3–0.6 pH-units) than wild-type (0.02–0.1 pH units) mice. Removing CO(2)/HCO(3)(−) inhibited acetylcholine-induced NO-mediated relaxations in arteries from NHE1 knockout but not wild-type mice. Without CO(2)/HCO(3)(−), effects of NO synthase and rho kinase inhibition on noradrenaline-induced contractions were smaller in arteries from NHE1 knockout than wild-type mice whereas the EC Ca(2+) response to acetylcholine, VSMC Ca(2+) response to noradrenaline and vasorelaxation to S-nitroso-N-acetylpenicillamine were unaffected. In conclusion, NHE1 mediates the Na(+)/H(+) exchange in ECs and VSMCs. Under physiological conditions, CO(2)/HCO(3)(−)-dependent mechanisms mask the pH(i)-regulatory function of NHE1. NHE1 knockout causes hypotrophy of VSMCs, reduced artery tension and lower blood pressure. At acidic pH(i), NO-mediated vasorelaxation and rho kinase-dependent VSMC Ca(2+) sensitivity are reduced.
Pubmed ID: 22351634 RIS Download
Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.
THIS RESOURCE IS NO LONGER IN SERVICE, documented May 10, 2017. A pilot effort that has developed a centralized, web-based biospecimen locator that presents biospecimens collected and stored at participating Arizona hospitals and biospecimen banks, which are available for acquisition and use by researchers. Researchers may use this site to browse, search and request biospecimens to use in qualified studies. The development of the ABL was guided by the Arizona Biospecimen Consortium (ABC), a consortium of hospitals and medical centers in the Phoenix area, and is now being piloted by this Consortium under the direction of ABRC. You may browse by type (cells, fluid, molecular, tissue) or disease. Common data elements decided by the ABC Standards Committee, based on data elements on the National Cancer Institute''s (NCI''s) Common Biorepository Model (CBM), are displayed. These describe the minimum set of data elements that the NCI determined were most important for a researcher to see about a biospecimen. The ABL currently does not display information on whether or not clinical data is available to accompany the biospecimens. However, a requester has the ability to solicit clinical data in the request. Once a request is approved, the biospecimen provider will contact the requester to discuss the request (and the requester''s questions) before finalizing the invoice and shipment. The ABL is available to the public to browse. In order to request biospecimens from the ABL, the researcher will be required to submit the requested required information. Upon submission of the information, shipment of the requested biospecimen(s) will be dependent on the scientific and institutional review approval. Account required. Registration is open to everyone., documented September 29, 2016. A workbench tool to make existing population genetic software more accessible and to facilitate the integration of new tools for analyzing patterns of DNA sequence variation, within a phylogenetic context. Collectively, SNAP tools can serve as a bridge between theoretical and applied population genetic analysis. The exploration of DNA sequence variation for making inferences on evolutionary processes in populations requires the coordinated implementation of a Suite of Nucleotide Analysis Programs (SNAP), each bound by specific assumptions and limitations.
View all literature mentionsThe SciCrunch Infrastructure was developed as a cooperative data platform to be used by diverse communities in making data more FAIR.
scicrunch.org
