Regulation of glucose production in newborn infants of diabetic mothers.

The glucose homeostasis in the infants of normal and diabetic mothers was elevated by examining the effects of exogenous glucose infusion at 4 mg/kg . min and quantifying the rats of glucose production and utilization. Five infants of insulin-dependent diabetic mothers (IDM), one infant of a gestationally diabetic mother and five infants of normal mothers were studied between 2-4 h of age. The rates of glucose production and utilization before and during glucose infusion were quantified by tracer dilution technique using [6,62H2] glucose tracer and gas chromatography-mass spectrometry. Fractional glucose uptake (Kt) was measured at the end of infusion by administering 0.5 g/kg glucose pulse. All diabetic women were under rigid metabolic control during pregnancy. Although basal plasma glucose levels at e 2-4 h were lower in the IDMs as compared with normal newborns (43.4 +/- 3.7 and 65.2 +/- 3.6 mg/dl, mean +/- S.E., respectively), the glucose production and utilization rates were not significantly different (3.35 +/- 0.26 and 3.39 +/- 0.08 mg/kg . min); therefore, the metabolic clearance rates were higher inthe IDMs (7.69 +/- 0.41 ml/kg . min) as compared with the normal newborn infant (5.20 +/- 0.20 ml/kg . min). Glucose infusion resulted in a greater suppression of endogenous glucose production rate in the normal newborn infants than in the IDMs. Glucose infusion resulted in an acceleration of Kt in the normals (2.38 +/- 0.25%/min). We conclude that rigid regulation of maternal diabetes normalizes glucose production rate in IDM; however, intermittent maternal hyperglycemia may result in altered regulation of hepatic glucose production.