Huttner W B, Krone W, Seitz H J, Tarnowski W
Biochem J. 1974 Sep;142(3):691-8. doi: 10.1042/bj1420691.
Dibutyryl cyclic AMP stimulated the activity of phosphoenolpyruvate carboxykinase in perfused livers of rats, fed on a low-protein diet, linearly over a 6h period. The enzyme activity was also significantly elevated by dexamethasone, the effect being considerably lower than that of the cyclic nucleotide. Since the time-course of phosphoenolpyruvate carboxykinase activity in response to dibutyryl cyclic AMP resembled that observed after dibutyryl cyclic AMP injection into intact animals, it is suggested that induction of the enzyme in vivo is due to a direct action of the cyclic nucleotide on the liver. Combined administration of dibutyryl cyclic AMP and glucocorticoids did not lead to an additive increase of liver phosphoenolpyruvate carboxykinase activity, either in vivo or in the perfused organ.
二丁酰环磷腺苷（Dibutyryl cyclic AMP）在6小时内线性刺激了以低蛋白饮食喂养的大鼠灌流肝脏中磷酸烯醇丙酮酸羧激酶的活性。地塞米松也显著提高了该酶的活性，但其作用远低于环核苷酸。由于磷酸烯醇丙酮酸羧激酶活性对二丁酰环磷腺苷的时间进程类似于将二丁酰环磷腺苷注射到完整动物后观察到的情况，因此表明该酶在体内的诱导是由于环核苷酸对肝脏的直接作用。无论是在体内还是在灌流器官中，联合给予二丁酰环磷腺苷和糖皮质激素都不会导致肝脏磷酸烯醇丙酮酸羧激酶活性的累加增加。
