Neutral amino acid transport across brain microvessel endothelial cell monolayers
Brain microvessel endothelial cells (BMEC) which form the blood-brain barrier (BBB) possess an amino acid carrier specific for large neutral amino acids (LNAA). The carrier is important for facilitating the delivery of nutrient LNAA's and centrally acting drugs that are LNAA's, to the brain. Bovine BMEC's were isolated and grown up to complete monolayers on regenerated cellulose-membranes in primary culture. To study the transendothelial transport of leucine, the monolayers were placed in a side-by-side diffusion cell, and transport across the monolayers followed with (/sup 3/H)-leucine. The transendothelial transport of leucine in this in vitro model was determined to be bidirectional, and time-, temperature-, and concentration-dependent. The transport of leucine was saturable and the apparent K/sub m/ and V/sub max/, 0.18 mM and 6.3 nmol/mg/min, respectively. Other LNAA's, including the centrally acting drugs, ..cap alpha..-methyldopa, L-DOPA, ..cap alpha..-methyl-tyrosine, and baclofen, inhibited leucine transport. The leucine carrier was also found to be stereospecific and not sensitive to inhibitors of active transport. These results are consistent with previous in vitro and in vivo studies. Primary cultures of BMEC's appear to be a potentially important tool for investigating at the cellular level, the transport mechanisms of the BBB.
- Research Organization:
- Univ. of Kansas, Lawrence
- OSTI ID:
- 5436137
- Report Number(s):
- CONF-8604222-; TRN: 86-026618
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:3; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
- Country of Publication:
- United States
- Language:
- English
Similar Records
Relationship between in vitro transendothelial permeability and in vivo single-pass brain extraction
Lysophosphatidic acid receptor, LPA6, regulates endothelial blood-brain barrier function: Implication for hepatic encephalopathy
Related Subjects
AMINO ACIDS
MEMBRANE TRANSPORT
BIOLOGICAL MODELS
BLOOD-BRAIN BARRIER
BRAIN
CATTLE
ENDOTHELIUM
IN VITRO
LEUCINE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMAL TISSUES
ANIMALS
BODY
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM
DOMESTIC ANIMALS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
NERVOUS SYSTEM
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
RUMINANTS
TISSUES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques