Rossi I, Olea J, Herias M, Pereda C, Felíu J E
Servicio de Gastroenterología, Hospital Puerta de Hierro, Facultad de Medicina, Universidad Autónoma de Madrid, Spain.
Metabolism. 1992 Mar;41(3):339-44. doi: 10.1016/0026-0495(92)90281-e.
In isolated rabbit gastric glands incubated in the presence of 1 mmol/L glucose, the content of fructose 2,6-bisphosphate (F-2,6-P2) was 5.7 +/- 0.5 pmol/mg dry weight. This value was progressively incremented by increasing glucose concentration in the incubation medium, and was almost doubled at 10 mmol/L glucose. Under these conditions, a close correlation could be established between the levels of F-2,6-P2 and the rate of L-lactate formation (r = .98; P less than .05). Both histamine (0.1 mmol/L) and cholecystokinin octapeptide (CCK-OCT; 0.1 mumol/L) increased L-lactate production, without significant changes in either F-2,6-P2 concentration or the amount of 6-phosphofructo-2-kinase in active form. In contrast, forskolin, which markedly increased the glandular content of cyclic adenosine monophosphate (cAMP), partially blocked glucose consumption and caused a significant reduction in both F-2,6-P2 levels and the proportion of 6-phosphofructo-2-kinase in active form. Furthermore, forskolin partially blocked the rate of glucose uptake by isolated gastric glands. Our results suggest a regulatory role of F-2,6-P2 in the control of the glycolytic flux in response to glucose, but not in its response to histamine or CCK-OCT.
在含有1 mmol/L葡萄糖的条件下孵育的离体兔胃腺中，果糖2,6-二磷酸（F-2,6-P2）的含量为5.7±0.5 pmol/mg干重。随着孵育培养基中葡萄糖浓度的增加，该值逐渐升高，在10 mmol/L葡萄糖时几乎翻倍。在这些条件下，F-2,6-P2水平与L-乳酸生成速率之间可建立密切相关性（r = 0.98；P<0.05）。组胺（0.1 mmol/L）和八肽胆囊收缩素（CCK-OCT；0.1 μmol/L）均增加L-乳酸的产生，而F-2,6-P2浓度或活性形式的6-磷酸果糖-2-激酶量均无显著变化。相反，能显著增加腺体内环磷酸腺苷（cAMP）含量的福斯可林部分阻断葡萄糖消耗，并导致F-2,6-P2水平和活性形式的6-磷酸果糖-2-激酶比例显著降低。此外，福斯可林部分阻断离体胃腺对葡萄糖的摄取速率。我们的结果表明，F-2,6-P2在响应葡萄糖时对糖酵解通量的控制中起调节作用，但在响应组胺或CCK-OCT时不起作用。
