Linked Life Data

1125240

Source:http://linkedlifedata.com/resource/pubmed/id/1125240

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1975-8-7
pubmed:abstractText
1. The kinetics of transport of glucose and four other hexoses through the blood-brain barrier were studied with a tritiated-water reference technique in the anesthetized rat. Brain clearance of [14-C]hexose was measured 15 s after a single injection of the hexose and 3-HOH reference into the common carotid artery. 2. Saturation of brain clearance of [14-C]hexose conformed to Michaelis-Menten kinetics. Linear transformation of the uptake data yielded the Km of carrier-mediated hexose transport: 2-deoxy-D-glucose 6 mM, D-glucose 9mM, 3-O-methyl-D-glucose and D-galactose 40 mM. A maximum transport velocity of 1.56 mumol/g per min was calculated and shown to be constant for all five hexoses. 3. The kinetics of 3-HOH and 3-0-methyl-D-[14-C]glucose efflux from brain to blood were studied with a modification of the water reference technique. An estimate of cerebral blood flow, 0.56 ml/g per min, was made from the efflux rate constant for 3-HOH, 0.61 min-1. The fractional extraction of 3-0-methyl-D-[14C]glucose uptake from blood was estimated from the efflux rate constant, 0.22 min-1, for this sugar and found to be 0.25. This value approximated the fractional extraction of 3-0-methyl-D-[14-C]glucose uptake that was determined from influx studies (0.24). These results indicated that the bidirectional movement of glucose across the blood brain barrier was symmetrical, which suggested that barrier sugar transport is equilibrative and not active. 4. Blood-brain barrier sugar transport was shown to be reversibly inhibited by phloretin, yet no modulation of transport was demonstrable after 2 or 8 days of starvation. Finally, regional analysis (olfactory bulb, caudate-putamen nucleus, thalamus-hypothalamus, and inferior-superior colliculi) demonstrated that, in addition to blood-brain barrier permeability, brain clearance of glucose was a function of cerebral blood flow.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
382
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
377-92
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1975
pubmed:articleTitle
Kinetics of blood-brain transport of hexoses.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.