Glycogen metabolism during human liver development.

Development of enzymes of glycogen metabolism in human fetal and neonatal liver was investigated. Glycogen was present in quantitatable amount from early gestational age onwards; however, ultrastructurally it could not be detected earlier than 20 weeks. Increase in glycogen synthetase a activity during 21-36 weeks of gestation subsequently resulted in glycogen accumulation. A rapid degradation of this glycogen storage, at birth, was accompanied by an elevation in glycogen phosphorylase a activity. The present investigation to be the first to provide a complete profile of glycogen storage and differentiation of glycogen metabolising enzymes in preparing the prenatal fetus for its independent nutritional life.