Regulation of gluconeogenesis from pyruvate and lactate in the isolated perfused rat liver.
Regulation of gluconeogenesis from pyruvate and lactate in the isolated perfused rat liver.
复制标题
离体灌注大鼠肝脏中丙酮酸和乳酸糖异生的调节。
DOI：
10.1016/0167-4889(86)90231-4
复制
发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Olson,MS
中科院分区：
文献类型：
--
作者：
Patel,TB;Olson,MS
The effects of glucagon and the α-adrenergic agonist, phenylephrine, on the rate of14CO2production and gluconeogenesis from [1-14C]lactate and [1-14C]pyruvate were investigated in isolated perfused livers of 24-h-fasted rats. Both glucagon and phenylephrine stimulated the rate of14CO2production from [1-14C]lactate but not from [1-14C]pyruvate. Neither glucagon nor phenylephrine affected the activation state of the pyruvate dehydrogenase complex in perfused livers derived from 24-h-fasted rats. 3-Mercaptopicolinate, an inhibitor of the phosphoenolpyruvate carboxykinase reaction, inhibited the rates of14CO2production and glucose production from [1-14C]lactate by 50% and 100%, respectively. Furthermore, 3-Mercaptopicolinate blocked the glucagon- and phenylephrine-stimulated14CO2production from [1-14C]lactate. Additionally, measurements of the specific radioactivity of glucose synthesized from [1-14C]lactate, [1-14C]pyruvate and [2-14C]pyruvate indicated that the14C-labeled carboxyl groups of oxaloacetate synthesized from 1-14C-labeled precursors were completely randomized and pyruvate → oxaloacetate → pyruvate substrate cycle activity was minimal. The present study also demonstrates that glucagon and phenylephrine stimulation of the rate of14CO2production from [1-14C]lactate is a result of increased metabolic flux through the phosphoenolpyruvate carboxykinase reaction, and phenylephrine-stimulated gluconeogenesis from pyruvate is regulated at step(s) between phosphoenolpyruvate and glucose.
