Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
|
| pubmed:dateCreated |
1977-4-28
|
| pubmed:abstractText |
gamma-Aminobutyric acid selectively increased Cl- permeability in isolated strips of crayfish abdominal muscle. Muscle fibers incubated in Van Harrevald's solution at room temperature took up 36Cl- to the extent of 700 ml/kg wet weight with a halftime of 2.5 min. During 15-S incubations, the control 36Cl- uptake space was 131 +/- 4 ml/kg (n = 60) and this was significantly increased by gamma-aminobutyric acid at 200 muM or higher concentrations to 177 +/- 4 ml/kg (n = 48, P less than 0.05). This effect was specific for chloride since gamma-aminobutyric acid did not increase the uptake by crayfish muscle of radioactive sucrose, inositol, or propionate. gamma-Aminobutyric acid stimulation of 36Cl- uptake is mediated by receptor-ionophore function since the process shows pharmacological properties virtually identical to those observed by electrophysiological techniques. The gamma-aminobutyric acid stimulation of Cl- permeability is dose dependent with 50% of the maximal effect at 40 muM gamma-aminobutyric acid and the dose vs. response curve is somewhat sigmoid. The gamma-aminobutyric acid agonist muscimol causes the same maximal effect on Cl- uptake as gamma-aminobutyric acid, but acts at 5-fold lower concentrations, i.e. is more potent. However, the partial agonist gamma-amino, beta-hydroxybutyric acid produced little or no stimulation of 36Cl- flux. The response to gamma-aminobutyric acid was blocked by 2 mM beta-guanidinopropionate or gamma-guanidinobutyrate, 0.5 mM bicuculline, and 10 muM picrotoxinin. Picrotoxinin inhibition was dose dependent with 50% inhibition occurring at 4 muM. Antagonists did not affect control 36Cl- uptake. These results confirm electrophysiological observations that the postsynaptic response to the inhibitory neurotransmitter gamma-aminobutyric acid involves a rapid increase in membrane permeability to Cl-.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Feb
|
| pubmed:issn |
0006-3002
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
4
|
| pubmed:volume |
464
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
519-29
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:836825-Aminobutyric Acids,
pubmed-meshheading:836825-Animals,
pubmed-meshheading:836825-Astacoidea,
pubmed-meshheading:836825-Biological Transport,
pubmed-meshheading:836825-Chlorides,
pubmed-meshheading:836825-Kinetics,
pubmed-meshheading:836825-Muscles,
pubmed-meshheading:836825-Permeability,
pubmed-meshheading:836825-Picrotoxin,
pubmed-meshheading:836825-Structure-Activity Relationship,
pubmed-meshheading:836825-gamma-Aminobutyric Acid
|
| pubmed:year |
1977
|
| pubmed:articleTitle |
gamma-Aminobutyric acid-stimulated chloride permeability in crayfish muscle.
|
| pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, U.S. Gov't, Non-P.H.S.
|