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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Extracellular ATP, ADP and GTP increased the intracellular free Ca2+ concentration ([Ca2+]i) in a suspension of isolated rat hepatocytes. The [Ca2+]i was determined by measuring fura-2 fluorescence, and its increase was biphasic. The initial transient rise was followed by a longer-lasting plateau. The peak of the early component preceded the plateau level of the second component. A time course of change in [Ca2+]i in single cells at 100 microM-ATP was very similar to that observed in the suspension system. Preincubation of hepatocytes with 40 mM-caffeine, 2 mM-oxalate or 60 microM-dantrolene sodium inhibited the P2 purinergic response. The plateau phase was not observed when measured in the presence of extracellular 100 microM-LaCl3 or in the absence of extracellular Ca2+. The distribution of [Ca2+]i in single hepatocytes was also determined by fluorescence image analysis. In the initial phase, the increase in [Ca2+]i is greater in the peripheral region than the central region of the cell. Degradation of extracellular ATP by ecto-ATPase in the hepatocyte suspension was measured; the amount of ATP degradation was less than 10-15% of the initial amount (100 microM) during the measurement of the intracellular [Ca2+]i in the cell suspension. Extracellular ATP stimulated glucose synthesis. The rate of glucose production also showed two components, the initial fast component within 1 min and the subsequent slower component. The rate of the initial fast component did not depend on the presence or absence of extracellular Ca2+, whereas the rate of the subsequent component depended on it. The present study shows that the initial transient rise in [Ca2+]i plays an important role in triggering the gluconeogenesis.

biochemical journal

Gluconeogenesis stimulated by extracellular ATP is triggered by the initial increase in the intracellular Ca2+ concentration of the periphery of hepatocytes