Cell density
Dotaz
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- MeSH
- cytologické techniky MeSH
- hybridní buňky imunologie MeSH
- myši MeSH
- protilátky MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
Alterations in ion channel expression and function known as "electrical remodeling" contribute to the development of hypertrophy and to the emergence of arrhythmias and sudden cardiac death. However, comparing current density values - an electrophysiological parameter commonly utilized to assess ion channel function - between normal and hypertrophied cells may be flawed when current amplitude does not scale with cell size. Even more, common routines to study equally sized cells or to discard measurements when large currents do not allow proper voltage-clamp control may introduce a selection bias and thereby confound direct comparison. To test a possible dependence of current density on cell size and shape, we employed whole-cell patch-clamp recording of voltage-gated sodium and calcium currents in Langendorff-isolated ventricular cardiomyocytes and Purkinje myocytes, as well as in cardiomyocytes derived from trans-aortic constriction operated mice. Here, we describe a distinct inverse relationship between voltage-gated sodium and calcium current densities and cell capacitance both in normal and hypertrophied cells. This inverse relationship was well fit by an exponential function and may be due to physiological adaptations that do not scale proportionally with cell size or may be explained by a selection bias. Our study emphasizes the need to consider cell size bias when comparing current densities in cardiomyocytes of different sizes, particularly in hypertrophic cells. Conventional comparisons based solely on mean current density may be inadequate for groups with unequal cell size or non-proportional current amplitude and cell size scaling.
- MeSH
- kardiomegalie * metabolismus patologie MeSH
- kardiomyocyty * metabolismus patologie MeSH
- metoda terčíkového zámku MeSH
- myši MeSH
- velikost buňky * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
... 61 -- Structure and distribution of membrane glycerophospholipids 62 -- Properties of sterols 64 -- Cell ... ... Cells and subcellular fractions 106 -- Balanced salt solutions ? ... ... 6 -- Composition of selected animal cell culture media 107 -- Selected animal cell lines ? ... ... culture media 113 -- MEM noncssential amino acids 114 -- Animal cell culture lines 115 -- Mammalian ... ... surface receptors and their mode of action 126 Properties of cell organelles 127 -- Contents -- >111 ...
Essential data series
xv, 224 s. : il. ; 19 cm
- MeSH
- biologie buňky MeSH
- buňky MeSH
- molekulární biologie MeSH
- Publikační typ
- příručky MeSH
- Konspekt
- Buněčná biologie. Cytologie
- NLK Obory
- cytologie, klinická cytologie
BACKGROUND AND AIMS: Stomatal density (SD) generally decreases with rising atmospheric CO2 concentration, Ca. However, SD is also affected by light, air humidity and drought, all under systemic signalling from older leaves. This makes our understanding of how Ca controls SD incomplete. This study tested the hypotheses that SD is affected by the internal CO2 concentration of the leaf, Ci, rather than Ca, and that cotyledons, as the first plant assimilation organs, lack the systemic signal. METHODS: Sunflower (Helianthus annuus), beech (Fagus sylvatica), arabidopsis (Arabidopsis thaliana) and garden cress (Lepidium sativum) were grown under contrasting environmental conditions that affected Ci while Ca was kept constant. The SD, pavement cell density (PCD) and stomatal index (SI) responses to Ci in cotyledons and the first leaves of garden cress were compared. (13)C abundance (δ(13)C) in leaf dry matter was used to estimate the effective Ci during leaf development. The SD was estimated from leaf imprints. KEY RESULTS: SD correlated negatively with Ci in leaves of all four species and under three different treatments (irradiance, abscisic acid and osmotic stress). PCD in arabidopsis and garden cress responded similarly, so that SI was largely unaffected. However, SD and PCD of cotyledons were insensitive to Ci, indicating an essential role for systemic signalling. CONCLUSIONS: It is proposed that Ci or a Ci-linked factor plays an important role in modulating SD and PCD during epidermis development and leaf expansion. The absence of a Ci-SD relationship in the cotyledons of garden cress indicates the key role of lower-insertion CO2 assimilation organs in signal perception and its long-distance transport.
- MeSH
- Arabidopsis cytologie účinky léků MeSH
- buk (rod) cytologie účinky léků MeSH
- dehydratace MeSH
- Helianthus cytologie účinky léků MeSH
- kotyledon účinky léků fyziologie MeSH
- Lepidium cytologie účinky léků MeSH
- oxid uhličitý farmakologie MeSH
- počet buněk MeSH
- průduchy rostlin cytologie účinky léků MeSH
- životní prostředí MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
