Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1988-6-20
pubmed:abstractText
We studied the effect of a gamma-aminobutyric acid (GABA)-A receptor-induced postsynaptic inhibition on regional CBF (rCBF) in awake humans. For this purpose we used a new specific GABA-A agonist, 4,5,6,7-tetrahydroisoxazolo(5,4)-pyridin-3-ol (THIP). As part of a new diagnostic procedure for the determination of which hemisphere subserved language, THIP was infused into the internal carotid artery 20 s before measurement of the rCBF. Administered by this route the THIP is distributed to the neocortex and neostriatum. THIP induced a dosage-dependent decrease of the rCBF. The rCBF decrease was not due to any direct effect on the cerebral vessels. The efficiency of the THIP-induced postsynaptic inhibition was tested by having the subjects voluntarily activate the inhibited cortex. During submaximal inhibition the subjects were able voluntarily to counteract decreases of rCBF in superior frontal cortex and motor cortex. Larger doses of THIP abolished this response and depressed the rCBF to baseline levels (20 ml/100 g/min). This was associated with 10-min total depression of function of the anterior two-thirds of the injected hemisphere. An analysis of the changes of rCBF in activated and nonactivated cortex--with and without THIP-induced inhibition--showed that it would be very unlikely that average increases in synaptic inhibition would increase rCBF in neocortical areas. Intracarotid injection of the water-soluble, nonirritative THIP is a very useful alternative to sodium amytal injection for determination of hemispheric dominance.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0271-678X
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
314-23
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
The effect of the GABA-A agonist THIP on regional cortical blood flow in humans. A new test of hemispheric dominance.
pubmed:affiliation
Department of Clinical Physiology and Neurology, Bispebjerg Hospital, Copenhagen, Denmark.
pubmed:publicationType
Journal Article