Upregulation of nutrient transport in fetal rabbit intestine by transamniotic substrate administration.

Intrauterine growth retardation complicates 3% to 7% of full-term pregnancies. The developing fetal gastrointestinal tract has the ability to absorb nutrients delivered via the amniotic sac. It is not clear, however, if this nutrient delivery does in fact aid in promoting additional maturation and development of the fetal gut. Sixteen pregnant New Zealand White rabbits underwent celiotomy on gestational day 24. The bicornuate uterus was exposed, and the ovarian-end fetuses were randomly assigned to either a control or a study group. A catheter was placed in the amniotic cavity in each side of the uterus for nutrient infusion and was secured in place. Both catheters were exteriorized; animals were partially restrained but were allowed free access to food and water. Immediately postoperatively, infusion of either a metabolizable carbohydrate (d-galactose; experimental group) or a nonmetabolized, nontransported carbohydrate (mannitol; control group) was carried out. Six days later, each fetus was harvested. ...