Linked Life Data

9593106

Source:http://linkedlifedata.com/resource/pubmed/id/9593106

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-7-1
pubmed:abstractText
The effects of enantiomers of the neurosteroid analogues, 3alpha-hydroxy-5alpha-pregnan-20-one (DHP) and 3alpha-hydroxy-5alpha-androstane-17beta-carbonitrile (ACN), and the benz[e]indene, BI-1, on synaptic currents were examined in microcultures of rat hippocampal neurons. Over the range of 0.1-10 microM, the (+)-enantiomers were more potent and effective than their (-)-enantiomeric counterparts in enhancing gamma-aminobutyric acid (GABA)A receptor-mediated evoked synaptic currents. The (+)-enantiomers had small effects on peak currents, but slowed the decay of inhibitory synaptic currents, resulting in 2-3-fold increases in charge transfer during inhibitory synaptic events at 10 microM. Similar prolongations of spontaneous miniature inhibitory postsynaptic currents (IPSCs) and responses to brief GABA pulses to outside-out patches suggest that the prolongations of evoked synaptic currents result primarily from postsynaptic effects. In contrast, the (-)-enantiomers had little effect on evoked IPSCs at concentrations < or = 1 microM, but enhanced inhibitory transmission at 10 microM. At concentrations < or = 1 microM, neither the (+)- nor (-)-enantiomers altered glutamate-mediated excitatory synaptic currents. At 10 microM, (+)-DHP and (+)-ACN depressed excitatory responses in a bicuculline-sensitive fashion, suggesting that direct chloride channel gating by the steroids contributed to the depression. These data indicate that certain steroids and benz[e]indenes augment inhibitory synaptic transmission enantioselectively and provide strong support for the hypothesis that steroids act at specific sites on synaptic GABA(A) receptors rather than via alteration of membrane lipids.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0887-4476
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
162-71
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Enantioselective modulation of GABAergic synaptic transmission by steroids and benz[e]indenes in hippocampal microcultures.
pubmed:affiliation
Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't