Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9-10
pubmed:dateCreated
1997-5-12
pubmed:abstractText
Utilising two point voltage-clamp techniques on Xenopus laevis oocytes expressing human (alpha 1 beta 1 gamma 2L) recombinant GABAA receptors, the GABA modulatory actions of six naturally occurring neurosteroids have been determined and compared with those of known positive allosteric modulators. The anaesthetic steroids 5 alpha- and 5 beta-pregnan-3 alpha-ol-20-one produced a concentration-dependent enhancement of the GABA-evoked current. The maximal enhancement of the agonist-induced response produced by these steroids was intermediate between that of pentobarbitone and diazepam, but much greater than that caused by bretazenil. For both the 5 alpha and 5 beta steroid a reduction of the 20 ketone group to form either the corresponding 20 alpha or 20 beta hydroxy steroid produced, in all cases, a reduction in potency and a decrease in the maximal effect. The relationship of steroid structure to these two parameters is considered. The influence of the alpha subtype (alpha x beta 1 gamma 2L, where x = 1, 2 or 3) for the behaviourally active 5 alpha-pregnan-3 alpha,20 alpha-diol is also determined. Although the maximal effect of the steroid is not influenced by the alpha subtype, the alpha 2-containing receptor exhibits a modest decrease (approximately 6-fold) in potency compared to alpha 1- and alpha 3-containing receptors. The results described here are discussed in relation to the distinct behavioural actions of the neurosteroids.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0028-3908
pubmed:author
pubmed:issnType
Print
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1223-31
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Modulation of human recombinant GABAA receptors by pregnanediols.
pubmed:affiliation
Department of Pharmacology and Clinical Pharmacology, Ninewells Hospital and Medical School, Dundee, U.K.
pubmed:publicationType
Journal Article