Ontogeny of blood-brain barrier function in ovine fetuses, lambs, and adults.
The ontogeny of regional blood-brain barrier function was quantified with the rate constant for influx (Ki) across the blood-brain barrier with the small molecular weight synthetic, inert hydrophilic amino acid alpha-aminoisobutyric acid (AIB) in chronically instrumented early (87 days of gestation, 60% of gestation) and late (137 days of gestation, 90% of gestation) gestation fetal, newborn (3 days of age), older (24 days of age), and adult (3 years of age) sheep. The Ki was significantly (P < 0.05) lower in the brain regions of the adult sheep and in most brain regions of newborn and older lambs compared with fetuses at 60 and 90% of gestation. The Ki exhibited regional brain heterogeneity (P < 0.05) in the five groups. The patterns of regional heterogeneity were accentuated (P < 0.05) in the younger groups. We conclude that ontogenic decreases in blood-brain barrier permeability are observed in ovine fetuses from 60% of gestation to maturity in the adult.
Stonestreet
B S
BS
Department of Pediatrics, Brown University School of Medicine, Providence, Rhode Island, USA.
Patlak
C S
CS
Pettigrew
K D
KD
Reilly
C B
CB
Cserr
H F
HF
D000375:Aging / Q000378:metabolism*; D000621:Aminoisobutyric Acids / Q000493:pharmacokinetics; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development / Q000378:metabolism*; D001812:Blood-Brain Barrier; D002199:Capillary Permeability; D005314:Embryonic and Fetal Development; D005333:Fetus / Q000378:metabolism*; D012756:Sheep / Q000196:embryology*
D000621:Aminoisobutyric Acids; C100049:2-aminoisobutyric acid