Neonatal intestinal lactase activity.

L T Weaver; M F Laker; R Nelson

doi:10.1136/adc.61.9.896

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Neonatal intestinal lactase activity.

L T Weaver·M F Laker·R Nelson

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Abstract

The sequential changes in intestinal lactase activity of 40 neonates were measured indirectly from the differential uptake and excretion of lactose and the non-metabolisable disaccharide lactulose contained in formula feeds. A daily decline in urinary lactose:lactulose excretion ratios, reflecting a rise in intestinal lactase activity, followed formula feeding. Percentage decline was related directly to gestation: full term infants displayed a fivefold greater decline in lactosuria than infants with a gestation of 28 weeks during the first 10 days of milk feeding. The difference between lactose:lactulose ingestion and excretion ratios suggests that within five days of starting feeds intestinal hydrolysis of lactose exceeds 98% efficiency, even in very preterm infants.

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Aging Animals Galactosidases Gestational Age Humans Infant, Newborn Intestines Lactose Lactulose Milk beta-Galactosidase Journal Article Research Support, Non-U.S. Gov't

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L T Weaver, M F Laker, R Nelson. 1986. Neonatal intestinal lactase activity.. https://doi.org/10.1136/adc.61.9.896

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