A B S T R A C T In adults, glucose infusion results in a decreased glucose production rate (GPR) as a mechanism for maintaining euglycemia. To document the development of glucose homeostasis, we derived the GPR in 23 preterm appropriate for gestational age infants, 14 term appropriate for gestational age infants, and in 6 adults. After a 3-h fast, the average plasma glucose and insulin concentration was measured and the GPR was derived. During glucose infusion (5.6±0.3 mg-kg-'min-'), compared with saline controls, the preterms had a rise in plasma glucose and plasma insulin, and the GPR was 1.4 mg * kg-'min-' (range, 0-4.4) vs. 3.0 mg * kg-'min-' (range, 1.8-4.1) (saline controls). In the term infants, only the plasma insulin concentration was elevated when the glucose infused (5.7±0.3 mg * kg-'min-') infants were compared with the saline controls and GPR was 0.4 mg kg-'min-' (range, 0-2.6) vs. 3.4 mg kg-'min-' (range, 2.8-5.7) (saline controls). In comparison to saline infused adults, glucose infusion (3.2±0.1 mg kg-'min-') resulted in a significant rise in plasma glucose and in plasma insulin; and the GPR was reduced to 0.1 mg kg-min-' (range, 0-0.3) from 2.0 mg*kg-'min-' (range, 1.5-2.4). 5 of 13 preterms and 2 of 7 term infants had persistent GPR during glucose infusion; in contrast, the GPR in all adults was unmeasurable. There was no correlation between the plasma glucose concentration and the GPR in the newborn or in the adult. Both

No abstract

No abstract

Insulin resistance has been reported to partially explain the clinical appearance of neonatal hyperglycemia. To determine the relative resistance to insulin of glucose production vs. glucose utilization, the euglycemic hyperinsulinemic clamp technique was employed for the first time in the human neonate and was combined with stable isotopic determination of glucose production and glucose utilization. The basal rates of glucose production and glucose utilization were determined, after which each neonate was clamped at his or her own euglycemic glucose concentration while receiving regular human insulin at one rate of 0.2, 0.5, 1.0, 2.0, or 4.0 mU. kg-1.min-1. Persistent glucose production (> or = 1 mg.kg-1.min-1) during the clamp was recorded for all groups. A significant increase in the glucose infusion rate (P < 0.001) and in percent glucose utilization (P < 0.01) occurred in the 2.0 and 4.0 mU.kg-1.min-1 insulin groups. Metabolic clearance rate of insulin was significantly greater in the neonate compared with the adult at the 2.0 mU.kg-1.min-1 insulin infusion rate (P = 0.036). Our results indicate that, in contrast to the adult, the neonate has persistent glucose production (P = 0.001) and greater peripheral sensitivity to insulin (P = 0.015).

No abstract

The results of this study demonstrate the safety and efficacy of a preterm formula supplemented with long-chain polyunsaturated fatty acids from single-cell oils.

No abstract

No abstract