Linked Life Data

17260949

Source:http://linkedlifedata.com/resource/pubmed/id/17260949

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-1-30
pubmed:abstractText
The competitive antagonist d-tubocurarine (curare) has greater potency at mouse than at human 5-hydroxytryptamine 3A (5-HT3A) receptors, despite 84% amino acid sequence identity between the receptors. Within the ligand binding domain of this receptor are six loops (A-F). A previous report demonstrated that loop C of the 5-HT3A receptor contributed to differential potency between the receptors [Hope, A. G. et al. (1999) Mol. Pharmacol. 55, 1037-1043]. The present study tested the hypothesis that loop F plays a significant role in conferring interspecies curare potency differences. Wild-type, chimeric, and point mutant 5-HT3A receptors were expressed in Xenopus oocytes, and two-electrode voltage clamp electrophysiological recordings were performed. Our data suggest that loops C and F contribute to curare potency, given that the curare IC50's (concentration of drug that produces 50% inhibition of the response) for chimeric human receptors with substitutions of mouse residues in loop C (40.07 +/- 2.52 nM) or loop F (131.8 +/- 5.95 nM) were intermediate between those for the mouse (12.99 +/- 0.77 nM) and human (1817 +/- 92.36 nM) wild-type receptors. Two human point mutant receptors containing mouse receptor substitutions in loop F (H-K195E or H-V202I) had significantly lower curare IC50's than that of the human receptor. The human double mutant receptor, H-K195E,V202I, had the same curare IC50 (133.8 +/- 6.38 nM) as that of the human receptor containing all six loop F mouse substitutions. These results demonstrate that two loop F residues make a significant contribution in determining curare potency at the 5-HT3A receptor.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
6
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1194-204
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
The role of loop F residues in determining differential d-tubocurarine potencies in mouse and human 5-hydroxytryptamine 3A receptors.
pubmed:affiliation
Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, 3601 Fourth Street, Lubbock, Texas 79430, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural