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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
11
|
| pubmed:dateCreated |
1985-12-18
|
| pubmed:abstractText |
Membrane chloride (Cl-) permeability was studied in a novel subcellular brain preparation, the synaptoneurosome. Using a radioactive tracer exchange technique, Cl- transport was determined by measuring 36Cl- efflux from rat cerebral cortical synaptoneurosomes. Barbiturates increased 36Cl- efflux in a dose-dependent manner with the following relative order of potency: 5-(1,3-dimethylbutyl)-5-ethyl barbituric acid ((-)-DMBB) greater than pentobarbital greater than secobarbital greater than (+)-DMBB greater than hexobarbital greater than amobarbital greater than mephobarbital. Phenobarbital and barbital were virtually inactive. A good correlation was observed between the potencies of these barbiturates in stimulating 36Cl- efflux and their anesthetic potencies in mice (r = 0.90, p less than 0.01) and their abilities to enhance [3H] diazepam binding to brain membranes (r = 0.77, p less than 0.05). The effect of pentobarbital in enhancing 36Cl- efflux was reversed by the gamma-aminobutyric acid (GABA) antagonists picrotoxin and bicuculline. Picrotoxin and bicuculline both decreased 36Cl- efflux in the absence of pentobarbital, suggesting the presence of endogenous GABA. Incubation of synaptoneurosomes with 4,4'-di-isothiocyano- or dinitro-2,2'-disulfonic acid stilbene, inhibitors of anion transport, also decreased both basal and pentobarbital-induced 36Cl- efflux. Pentobarbital (500 microM) was most effective in inducing 36Cl- efflux in the cerebellum, hippocampus, and cortex (23.7, 23.6, and 22.5%, respectively), and was less effective in stimulating 36Cl- efflux in the striatum (15.1%) and pons-medulla (6.2%). The relative efficacy of pentobarbital in enhancing 36Cl- efflux among these various brain regions was highly correlated (r = 0.96, p 0.01) with the relative densities of [35S]-t-butylbicyclophosphorothionate-binding sites, a measure of GABA-gated Cl- channel density.(ABSTRACT TRUNCATED AT 250 WORDS)
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Amobarbital,
http://linkedlifedata.com/resource/pubmed/chemical/Barbiturates,
http://linkedlifedata.com/resource/pubmed/chemical/Bicuculline,
http://linkedlifedata.com/resource/pubmed/chemical/Chlorides,
http://linkedlifedata.com/resource/pubmed/chemical/Hexobarbital,
http://linkedlifedata.com/resource/pubmed/chemical/Mephobarbital,
http://linkedlifedata.com/resource/pubmed/chemical/Pentobarbital,
http://linkedlifedata.com/resource/pubmed/chemical/Picrotoxin,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, GABA-A,
http://linkedlifedata.com/resource/pubmed/chemical/Rubidium,
http://linkedlifedata.com/resource/pubmed/chemical/Secobarbital
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Nov
|
| pubmed:issn |
0270-6474
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
5
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
2963-70
|
| pubmed:dateRevised |
2003-11-14
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| pubmed:meshHeading |
pubmed-meshheading:2997410-Amobarbital,
pubmed-meshheading:2997410-Animals,
pubmed-meshheading:2997410-Barbiturates,
pubmed-meshheading:2997410-Bicuculline,
pubmed-meshheading:2997410-Brain,
pubmed-meshheading:2997410-Cell Membrane Permeability,
pubmed-meshheading:2997410-Cerebral Cortex,
pubmed-meshheading:2997410-Chlorides,
pubmed-meshheading:2997410-Dose-Response Relationship, Drug,
pubmed-meshheading:2997410-Hexobarbital,
pubmed-meshheading:2997410-Male,
pubmed-meshheading:2997410-Mephobarbital,
pubmed-meshheading:2997410-Pentobarbital,
pubmed-meshheading:2997410-Picrotoxin,
pubmed-meshheading:2997410-Rats,
pubmed-meshheading:2997410-Rats, Inbred Strains,
pubmed-meshheading:2997410-Receptors, GABA-A,
pubmed-meshheading:2997410-Rubidium,
pubmed-meshheading:2997410-Secobarbital,
pubmed-meshheading:2997410-Synapses
|
| pubmed:year |
1985
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| pubmed:articleTitle |
Characterization of barbiturate-stimulated chloride efflux from rat brain synaptoneurosomes.
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| pubmed:publicationType |
Journal Article
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