The Influence of Ca on Gluconeogenesis Stimulation by Glucagon in the Liver of Arthritic Rats
نویسندگان
چکیده
Ca participates in the stimulation of hepatic gluconeogenesis by glucagon and there is evidence that Ca fluxes are modified in arthritic rats. These findings raise the question whether hepatic gluconeogenesis in arthritic rats responds differently to glucagon and Ca. The experimental system was the isolated perfused rat liver. In the presence of Ca, stimulation of hepatic gluconeogenesis by glucagon in arthritic rats was equal to that in normal rats in absolute terms, but higher in relative terms (104.5 and 45.2%, respectively). In the absence of Ca, however, stimulation of hepatic gluconeogenesis by glucagon in arthritic rats was smaller in both absolute and relative terms (18.5 and 41.9%, respectively). It can be concluded that the Ca-dependent component of gluconeogenesis activation by glucagon is more important in arthritic than in normal rats.
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