Linked Life Data

2171963

Source:http://linkedlifedata.com/resource/pubmed/id/2171963

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-12-12
pubmed:abstractText
The effects of trimebutine maleate on [3H]nitrendipine binding to guinea-pig ileal smooth muscle membranes and Ca2(+)-induced contraction of the taenia cecum were studied. Specific binding of [3H]nitrendipine to smooth muscle membranes was saturable, with a KD value and maximum number of binding sites (Bmax) of 0.16 nM and 1070 fmol/mg protein, respectively. Trimebutine inhibited [3H]nitrendipine binding in a concentration-dependent manner with a Ki value of 9.3 microM. In the presence of trimebutine (10 microM), Scatchard analysis indicated a competitive-like inhibition with a decrease in the binding affinity (0.31 nM) without a change in Bmax (1059 fmol/mg protein). However, a dissociation experiment using trimebutine (10 or 100 microM) showed that the decreased affinity was due to an increase of the dissociation rate constant of [3H]nitrendipine binding to the membrane. In mechanical experiments using the taenia cecum, trimebutine (3-30 microM) caused a parallel rightward shift of the dose-response curve for the contractile response to a higher concentration range of Ca2+ under high-K+ conditions in a noncompetitive manner. These results suggest that trimebutine has negative allosteric interactions with 1,4-dihydropyridine binding sites on voltage-dependent Ca2+ channels and antagonizes Ca2+ influx, consequently inhibiting contractions of intestinal smooth muscle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0014-2999
pubmed:author
pubmed:issnType
Print
pubmed:day
31
pubmed:volume
189
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
71-6
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Allosteric interaction of trimebutine maleate with dihydropyridine binding sites.
pubmed:affiliation
Biological Research Laboratory, Tanabe Seiyaku Co., Ltd., Saitama, Japan.
pubmed:publicationType
Journal Article