Matches in SemOpenAlex for { <https://semopenalex.org/work/W52647663> ?p ?o ?g. }
Showing items 1 to 61 of
61
with 100 items per page.
- W52647663 endingPage "98" @default.
- W52647663 startingPage "187" @default.
- W52647663 abstract "Previous work has shown that beating heart muscle cells with leaky sarcolemmae take up Ca2+ from the medium at a rate of 5.4 nmol/min/mg of protein while beating at a rate of 44 b.p.m. In the present work, we have used fragments of myocardium (MF), composed of such cells, to measure Ca2+ effux velocity and to compare influx and efflux rates to contraction frequency. The MF were estimated to be three cells thick, five cells wide, and three cells long, on the average. With MF suspended in fresh Pi-buffered medium containing 8.7 mumol/liter total Ca2+, the initial velocity of Ca2+ uptake (Vi) was much greater than the initial velocity of efflux (Vo). Vi, but not Vo, covaried with beating as a function of temperature and also showed ATP dependence. Thus, uptake, but not efflux, is a controlled process coupled to beating under these conditions. When cells were preloaded with Ca2+ and resuspended in Ca2+-depleted medium (total Ca2+ about 1 mumol/liter), approximating the steady state condition, Vi was reduced while Vo increased proportionally. These data suggest that contraction-activating Ca2+ is derived from extracellular sources during the pre-steady state conditions used here. Derivation from intracellular sites could occur in the steady state. The pre-steady state results conflict with mechanical behavior studies by us and others and, with Ca2+ flux in isolated sarcoplasmic reticulum (SR). The steady state results suggest that this conflict may be due to differences in Ca2+ loading and [Ca2+]i/[Ca2+]o." @default.
- W52647663 created "2016-06-24" @default.
- W52647663 creator A5003050869 @default.
- W52647663 date "1980-01-01" @default.
- W52647663 modified "2023-09-23" @default.
- W52647663 title "Ca2+ flux and beating in leaky heart cells." @default.
- W52647663 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/7423036" @default.
- W52647663 hasPublicationYear "1980" @default.
- W52647663 type Work @default.
- W52647663 sameAs 52647663 @default.
- W52647663 citedByCount "0" @default.
- W52647663 crossrefType "journal-article" @default.
- W52647663 hasAuthorship W52647663A5003050869 @default.
- W52647663 hasConcept C12554922 @default.
- W52647663 hasConcept C134018914 @default.
- W52647663 hasConcept C147789679 @default.
- W52647663 hasConcept C158617107 @default.
- W52647663 hasConcept C163415756 @default.
- W52647663 hasConcept C178790620 @default.
- W52647663 hasConcept C185592680 @default.
- W52647663 hasConcept C200082930 @default.
- W52647663 hasConcept C28406088 @default.
- W52647663 hasConcept C55493867 @default.
- W52647663 hasConcept C68709404 @default.
- W52647663 hasConcept C79879829 @default.
- W52647663 hasConcept C8171440 @default.
- W52647663 hasConcept C86803240 @default.
- W52647663 hasConceptScore W52647663C12554922 @default.
- W52647663 hasConceptScore W52647663C134018914 @default.
- W52647663 hasConceptScore W52647663C147789679 @default.
- W52647663 hasConceptScore W52647663C158617107 @default.
- W52647663 hasConceptScore W52647663C163415756 @default.
- W52647663 hasConceptScore W52647663C178790620 @default.
- W52647663 hasConceptScore W52647663C185592680 @default.
- W52647663 hasConceptScore W52647663C200082930 @default.
- W52647663 hasConceptScore W52647663C28406088 @default.
- W52647663 hasConceptScore W52647663C55493867 @default.
- W52647663 hasConceptScore W52647663C68709404 @default.
- W52647663 hasConceptScore W52647663C79879829 @default.
- W52647663 hasConceptScore W52647663C8171440 @default.
- W52647663 hasConceptScore W52647663C86803240 @default.
- W52647663 hasLocation W526476631 @default.
- W52647663 hasOpenAccess W52647663 @default.
- W52647663 hasPrimaryLocation W526476631 @default.
- W52647663 hasRelatedWork W2008029056 @default.
- W52647663 hasRelatedWork W2039334425 @default.
- W52647663 hasRelatedWork W2044438306 @default.
- W52647663 hasRelatedWork W2046092466 @default.
- W52647663 hasRelatedWork W2070229124 @default.
- W52647663 hasRelatedWork W2410085250 @default.
- W52647663 hasRelatedWork W2472870349 @default.
- W52647663 hasRelatedWork W3212407440 @default.
- W52647663 hasRelatedWork W4226452802 @default.
- W52647663 hasRelatedWork W84773772 @default.
- W52647663 hasVolume "2" @default.
- W52647663 isParatext "false" @default.
- W52647663 isRetracted "false" @default.
- W52647663 magId "52647663" @default.
- W52647663 workType "article" @default.