THE BLOOD-BRAIN-BARRIER GLUCOSE-TRANSPORTER IS CONSERVED IN PRETERM AND TERM NEWBORN-INFANTS

Glucose, an essential substrate for brain oxidative metabolism, is tra nsported across the adult blood-brain barrier by Glut 1, a facilitativ e glucose transporter. Employing postmortem human brain samples and We stern blot analysis, we demonstrated the presence of a 47-55 kilodalto n Glut 1 protein in preterm and term newborn. The level of Glut 1 in b oth the preterm (24-33 weeks; n = 12) and term (38-40 weeks; n = 4) ne onates was comparable to that of the adult (n = 5). Using paraffin bra in sections and immunohistochemical analysis, in the preterm (24-25 we eks) and term (40 weeks) infant, similar to the adult we demonstrated the presence of Glut 1 in microvascular endothelial cells which consti tute blood-brain barrier forming cells. The ontogenic conservation of the blood-brain barrier Glut 1 makes detecting defective glucose trans port across the neonatal blood-brain barrier feasible. Genetic or acqu ired defects in Glut 1 can impede the transport of glucose across the blood-brain barrier, thereby, resulting in irreversible neurological c ompromise during infancy. Earlier detection during the neonatal period , and appropriate intervention, may set the stage for altering the out come of affected infants.