English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Neonatal ventricular myocytes that were incubated in a well-defined serum-free medium containing 50 mM KCl did not contract and maintained stable cell size, as assessed by the protein/DNA ratio. The present study utilized KCl-arrested cells to examine the effect of constant rates of synchronous contraction in normal [K+]o (4 mM) as a physiological stimulus for myocyte growth. Cell growth increased following the onset of contraction when measured over 3 days. The rate of protein synthesis was accelerated in parallel by contraction, but the rate of protein degradation remained similar to rates in noncontracting cells. The capacity for protein synthesis was estimated by total RNA content and was increased in contracting as compared with KCl-arrested cells. This increase was accompanied by faster rates of RNA synthesis as determined from the incorporation of [3H]uridine into RNA and the specific activity of the cellular UTP pool. The rate of RNA degradation was accelerated during contraction but the difference between the rates of RNA synthesis and degradation resulted in net RNA accumulation of 49% after 3 days. These data demonstrated that 1) contractile activity stimulated myocyte growth through an increased capacity for protein synthesis and 2) the increased capacity for protein synthesis involved acceleration of the rate of RNA synthesis. Since enhancement of protein synthetic capacity is a common feature of myocyte hypertrophy in vivo and in vitro, this model can be used to examine the regulation of ribosome synthesis during hypertrophic growth.

Contraction modulates the capacity for protein synthesis during growth of neonatal heart cells in culture.