Glucose transporter of the blood-brain barrier and brain in chronic hyperglycemia.
The effect of chronic hyperglycemia on the glucose transporter moiety of the blood-brain barrier and cerebral cortex was studied in rats 3 weeks after the administration of a single intravenous dose of streptozotocin (60 mg/kg), using specific [3H]cytochalasin B binding methods. Streptozotocin-treated rats developed hyperglycemia, as well as polydipsia and polyuria, and failed to gain weight. The density of D-glucose-displaceable cytochalasin B binding sites in the brain microvessels of streptozotocin-treated hyperglycemic rats was increased by about 30% compared with those of control rats, without change in the affinity of binding. Chronic hyperglycemia had no effect on the density or affinity of specific binding of cytochalasin B to cerebral cortical membranes. These findings do not support the hypothesis that glucose transporters in brain microvessels comprising the blood-brain barrier are "down-regulated" in chronic hyperglycemia.
Harik
S I
SI
Department of Neurology, University Hospitals of Cleveland, OH 44106.
Gravina
S A
SA
Kalaria
R N
RN
D000818:Animals; D001812:Blood-Brain Barrier; D001921:Brain / Q000098:blood supply / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism; D003571:Cytochalasin B / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D008297:Male; D008833:Microcirculation / Q000378:metabolism; D009004:Monosaccharide Transport Proteins / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D009004:Monosaccharide Transport Proteins; D003571:Cytochalasin B