| RRC ID |
6521
|
| 著者 |
Muntasir HA, Rashid M, Komiyama T, Kawakami J, Nagatomo T.
|
| タイトル |
Identification of amino acid residues important for sarpogrelate binding to the human 5-hydroxytryptamine2A serotonin receptor.
|
| ジャーナル |
J Pharmacol Sci
|
| Abstract |
The purpose of the present study was to examine 5-hydroxytryptamine (5-HT)(2A)-receptor sarpogrelate interactions by site-directed mutagenesis. Based on molecular modeling studies, aspartic acid (Asp)155[3.32] and tryptophan (Trp)151[3.28] in transmembrane helix (TMH) III and Trp336[6.48] in TMH VI of the 5-HT(2A) receptor were found to interact with sarpogrelate. All of these residues were mutated to alanine (Ala). The Asp3.32Ala mutant did not exhibit any affinity for [(3)H]ketanserin, whereas the Trp3.28Ala mutant showed a markedly decrease in the binding affinity for [(3)H]ketanserin (K(d) >10,000 nM). Therefore, it was not possible to find any sarpogrelate affinity to the mutants using [(3)H]ketanserin. The mutation also abolished agonist-stimulated formation of [(3)H]inositol phosphates (IP) in both cases. On the other hand, the Trp6.48Ala mutant showed reduced binding affinity for [(3)H]ketanserin (K(d) 2.0 nM vs 0.8 nM for the wild-type receptor) and had reduced affinity for sarpogrelate (pK(i) value of 5.71 vs 9.06 for the wild-type receptor). The Trp6.48Ala mutant also showed the greatest decrease in sensitivity to sarpogrelate (pK(b) value 8.81 for wild-type and 5.11 for mutant) in inhibiting agonist-stimulated IP formation. These results provide direct evidence that Asp3.32, Trp3.28, and less importantly, Trp6.48 are responsible for the interaction between the 5-HT(2A) receptor and sarpogrelate. In addition, these results support the findings obtained from molecular modeling studies.
|
| 巻・号 |
102(1)
|
| ページ |
55-63
|
| 公開日 |
2006-9-1
|
| DOI |
10.1254/jphs.fp0060171
|
| PII |
JST.JSTAGE/jphs/FP0060171
|
| PMID |
16974069
|
| MeSH |
Amino Acids / metabolism*
Animals
Binding, Competitive / drug effects
Blotting, Western
COS Cells
Cell Line
Cells, Cultured
Chlorocebus aethiops
DNA / genetics
Humans
Inositol Phosphates / metabolism
Ketanserin / metabolism
Ligands
Models, Molecular
Mutagenesis, Site-Directed
Receptor, Serotonin, 5-HT2A / genetics
Receptor, Serotonin, 5-HT2A / metabolism*
Serotonin Antagonists / metabolism*
Serotonin Receptor Agonists / pharmacology
Succinates / metabolism*
Transfection
|
| IF |
2.835
|
| 引用数 |
12
|
|
WOS 分野
|
PHARMACOLOGY & PHARMACY
|
| リソース情報 |
| ヒト・動物細胞 |
|
