Modulation of pyruvate dehydrogenase kinase activity in cultured hepatocytes by glucagon and n-octanoate.
نویسندگان
چکیده
The activity of pyruvate dehydrogenase kinase in extracts of mitochondria from rat hepatocytes cultured for 21 h in medium 199 was increased 2.5-fold by the presence of 55 nM-glucagon and 1 mM-sodium n-octanoate in the culture medium. The change was comparable with that induced in vivo by 48 h starvation. The potential contribution of branched-chain complex to estimates of PDH-complex activity in rat liver mitochondria has been defined.
منابع مشابه
Longer-term regulation of pyruvate dehydrogenase kinase in cultured rat hepatocytes.
The activities of pyruvate dehydrogenase (PDH) kinase and of PDH kinase activator protein (KAP) were increased 2-2.4-fold during 25 h of culture of hepatocytes from fed rats with glucagon plus n-octanoate. PDH kinase activity in hepatocytes from starved rats (initially 2.2 x fed control) fell during 25 h of culture in medium 199 (to 1.5 x fed control), but was maintained by glucagon plus octano...
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عنوان ژورنال:
- The Biochemical journal
دوره 234 1 شماره
صفحات -
تاریخ انتشار 1986