Casteleijn E, van Rooij H C, van Berkel T J, Koster J F
FEBS Lett. 1986 Jun 9;201(2):193-7. doi: 10.1016/0014-5793(86)80607-x.
Isolated rat hepatocytes were incubated in the absence or presence of glucagon and the activity of fructose-1,6-bisphosphatase was measured in cell extracts. After glucagon treatment the Vmax was increased (20-50%) whereas the Km remained unchanged. The stimulation was complete at 5 min after addition of glucagon. The glucagon concentration needed for maximal stimulation was 10(-9) M. After gel filtration the fructose-1,6-bisphosphatase activity in extracts of glucagon-treated cells was lowered to the control level. The effect of glucagon could not be completely mimicked by dibutyryl cAMP. The data indicate that in addition to the possible regulatory role of enzyme phosphorylation, a positive effector is involved in the stimulation of fructose-1,6-bisphosphatase activity by glucagon.
将分离的大鼠肝细胞在不存在或存在胰高血糖素的情况下进行孵育，并在细胞提取物中测量果糖-1,6-二磷酸酶的活性。胰高血糖素处理后，Vmax增加（20%-50%），而Km保持不变。添加胰高血糖素后5分钟刺激完成。最大刺激所需的胰高血糖素浓度为10^(-9) M。凝胶过滤后，胰高血糖素处理细胞提取物中的果糖-1,6-二磷酸酶活性降至对照水平。二丁酰环磷腺苷不能完全模拟胰高血糖素的作用。数据表明，除了酶磷酸化可能的调节作用外，一种正效应物参与了胰高血糖素对果糖-1,6-二磷酸酶活性的刺激。
