[Binding activity of polypeptide containing human Na+, K+-ATPase alpha1 subunit M1-M2 extracellular segment].
OBJECTIVE
To assess the binding activity of polypeptide containing human Na+, K+-ATPase alpha1 subunit M1-M2 extracellular segment (HES1 derivative).


METHODS
HES1 derivative was synthesized by Fmoc method and purified by high-performance liquid chromatography-mass spectrometry, and its binding activity was identified by radioligand binding assay.


RESULTS
3H-ouabain and synthetic HES1 derivative showed some binding activity with the equilibrium dissociation constant (KD) of 24.58 nmol/L, with the the receptor density of 492.43 fmol x mg(-1) pro. and IC50 of 3.078 x 10(-7) mol/L.


CONCLUSIONS
HES1 derivative can bind to ouabain and has the potential of becoming an effective therapeutic agent.
Zhang
Ming-juan
MJ
Department of Cardiology, Second Affiliated Hospital, Xi'an Jiaotong University College of Medicine, Xi'an 710004, China. zhangmingjuanyj@yahoo.com
Yang
Jun
J
Zhu
Can-zhan
CZ
Duan
Zong-ming
ZM
Niu
Xiao-lin
XL
Wang
Rong
R
D001665:Binding Sites / Q000187:drug effects; D005110:Extracellular Space / Q000378:metabolism; D006801:Humans; D010042:Ouabain / Q000737:chemistry* / Q000494:pharmacology; D010455:Peptides / Q000737:chemistry*; D011485:Protein Binding; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
D010455:Peptides; D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase