Fowden A L, Mijovic J, Ousey J C, McGladdery A, Silver M
Physiological Laboratory, Cambridge, UK.
J Dev Physiol. 1992 Sep;18(3):137-42.
The activities of glucose-6-phosphatase (G6P), fructose diphosphatase, phosphoenolpyruvate carboxykinase (PEPCK), aspartate and alanine transferases were measured in liver and kidney of fetal foals between 100-318 days of gestation (term approximately 335 days) and during the immediate postnatal period (0-48 h after birth). All 5 enzymes could be detected in the fetal liver and kidney at the youngest gestational age studied. Mean fetal activities were lower than those observed in their mothers and showed no change with gestational age for the majority of enzymes studied. However, renal PEPCK and renal and hepatic G6P did increase towards term. At birth, hepatic and renal activities of these two enzymes were higher than those found in late gestation or in the adult animals. There was no apparent change in the activities of any of the other enzymes at birth. In late gestation (80-90% gestation), the activities of G6P and PEPCK in the foal were low compared to those in other species at the same stage of gestation. Similarly, the perinatal increase in enzyme activity occurred closer to term in the foal than in most other species. These observations indicate that maturation of glucogenic capacity occurs relatively late in the fetal foal and suggests that this process may be dependent on the prepartum rise in fetal cortisol as occurs in other species.
在妊娠100 - 318天（足月约335天）的胎儿马驹以及出生后即刻（出生后0 - 48小时）的肝脏和肾脏中，测定了葡萄糖-6-磷酸酶（G6P）、果糖二磷酸酶、磷酸烯醇丙酮酸羧激酶（PEPCK）、天冬氨酸转氨酶和丙氨酸转氨酶的活性。在所研究的最小胎龄时，所有这5种酶均可在胎儿肝脏和肾脏中检测到。胎儿的平均活性低于其母亲所观察到的活性，并且对于所研究的大多数酶而言，其活性并未随胎龄发生变化。然而，肾PEPCK以及肾和肝G6P在足月时确实有所增加。出生时，这两种酶的肝脏和肾脏活性高于妊娠晚期或成年动物中的活性。出生时其他任何一种酶的活性均无明显变化。在妊娠晚期（妊娠80 - 90%），与处于相同妊娠阶段的其他物种相比，马驹体内G6P和PEPCK的活性较低。同样，马驹体内酶活性在围产期的增加比大多数其他物种更接近足月时发生。这些观察结果表明，糖原异生能力的成熟在胎儿马驹中发生得相对较晚，并且表明该过程可能像在其他物种中一样依赖于产前胎儿皮质醇的升高。
