Apr 1, 1981

High- and low-affinity transport of D-glucose from blood to brain

Journal of Neurochemistry
A Gjedde

Abstract

Measurements of the unidirectional blood-brain glucose flux in rat were incompatible with a single set of kinetic constants for transendothelial transport. At least two transfer mechanisms were present: a high-affinity, low-capacity system, and a low-affinity, high-capacity system. The low-affinity system did not represent passive diffusion because it distinguished between D- and L-glucose. The Tmax and Km for the high-affinity system were 0.16 mmol 100 g-1 min-1 and 1 mM; for the low-affinity system, approximately 5 mmol 100 g-1 min-1 and approximately 1 M. With these values, physiological glucose concentrations were not sufficient to saturate the low-affinity system. In normoglycemia, therefore, three independent pathways of glucose transport from blood to brain appear to exist: a high-affinity facilitated diffusion pathway of apparent permeability 235 X 10(-7) cm s-1, a specific but nonsaturable diffusion pathway of permeability 85 x 10(-7) cm s-1, and a nonspecific passive diffusion pathway of permeability 2 x 10(-7) cm s-1.

Mentioned in this Paper

Biochemical Pathway
Blood - Brain Barrier Anatomy
Brain
Glucose, (beta-D)-Isomer
Glucose, (L)-Isomer
Glucose
Glucose Transport
Facilitated Diffusion
Blood Glucose

About this Paper

Related Feeds

Blood Brain Barrier

The blood brain barrier is a border that separates blood from cerebrospinal fluid. Discover the latest search on this highly selective semipermeable membrane here.

Blood Brain Barrier Chips

The blood brain barrier (BBB) is comprised of endothelial cells that regulate the influx and outflux of plasma concentrations. Lab-on-a-chip devices allow scientists to model diseases and mechanisms such as the passage of therapeutic antibodies across the BBB. Discover the latest research on BBB chips here.

Related Papers

Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism
C S PatlakJ D Fenstermacher
Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism
Naoto OmataY Yonekura
Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism
H KuwabaraA Gjedde
© 2020 Meta ULC. All rights reserved