| RRC ID |
6528
|
| 著者 |
Takahashi K, Hossain M, Ahmed M, Bhuiyan MA, Ohnuki T, Nagatomo T.
|
| タイトル |
Asp125 and Thr130 in transmembrane domain 3 are major sites of alpha1b-adrenergic receptor antagonist binding.
|
| ジャーナル |
Biol Pharm Bull
|
| Abstract |
Site-directed mutagenesis was used to investigate the molecular interactions involved in prazosin binding to the human alpha(1b)-adrenergic receptor (alpha(1b)-AR) receptor. Based on molecular modeling studies, Thr130 and Asp125 in transmembrane region III of the alpha(1b)-AR receptor were found to interact with prazosin. Thr130 and Asp125 were mutated to alanine (Ala) and expressed in HEK293 cells. The radioligand [(3)H]prazosin did not show any binding to Asp125Ala mutant of alpha(1b)-AR. Therefore, it was not possible to find any prazosin affinity to the mutant using the radioligand [(3)H]prazosin. The mutation also abolished phenylephrine-stimulated inositol phosphate (IP) formation of [(3)H]myo-inositol. On the other hand, the Thr130Ala mutant showed reduced binding affinity for [(3)H]prazosin (dissociation constant, K(d) 674.27 pM versus 90.27 pM for the wild-type receptor) and had reduced affinity for both tamsulosin and prazosin (11-fold and 9-fold, respectively). However, the Thr130Ala mutant receptor retained the ability to stimulate the formation of [(3)H]myo-inositol. The results provide direct evidence that Asp125 and Thr130 are responsible for the interactions between alpha(1b)-AR receptor and radioligand [(3)H]prazosin as well as tamsulosin.
|
| 巻・号 |
30(10)
|
| ページ |
1891-4
|
| 公開日 |
2007-10-1
|
| DOI |
10.1248/bpb.30.1891
|
| PII |
JST.JSTAGE/bpb/30.1891
|
| PMID |
17917257
|
| MeSH |
Adrenergic alpha-Antagonists / metabolism*
Alanine / chemistry
Alanine / genetics
Aspartic Acid / chemistry*
Binding, Competitive / drug effects
Blotting, Western
Cells, Cultured
DNA, Complementary / genetics
Humans
Hydrolysis
Ligands
Models, Molecular
Phosphatidylinositols / metabolism
Prazosin / metabolism
Receptors, Adrenergic, alpha-1 / chemistry
Receptors, Adrenergic, alpha-1 / genetics
Receptors, Adrenergic, alpha-1 / metabolism*
Threonine / chemistry*
Transfection
|
| IF |
1.863
|
| 引用数 |
8
|
|
WOS 分野
|
PHARMACOLOGY & PHARMACY
|
| リソース情報 |
| ヒト・動物細胞 |
|
