Issue Archive

Activity identification of peptide containing rat sodium pump #alpha#2 subunit M1--M2 extramembrane fragment {sl in vitro}

Zhang Mingjuan, Yang Jun, Qiang Lei, Wang Rong, Song Yafan, Niu Xiaolin

Department of Cardiology, the Second Affiliated Hospital, Medical College of Xi'an Jiaotong University.Xi'an 710004,Shaanxi

Abstract

In order to explore the activity of a peptide containing rat sodium pump #alpha#2 subunit M1-M2 extramembrane fragment (RES2 derivative) in vitro, the peptide (Len-Ala-Ala-Met-Glu-Asp-Glu-Pro-Ser-Asn-Asp-Asn-Gly-Gly-Gly-Ser) was synthesized by pep-tide synthesizer with Fmoc method and purified by high performance liquid chromatography (HPLC). Its binding activity wasidentified by radioligand-receptor binding assay (RRA) and its bioactivity was measured by erythrocyte ~(86)Rb uptake. The results ofsaturation binding experiment and competitive binding experiment showed that the synthesized RES2 derivative had the capability tobind to ~(3)H-ouabain. The dissociation constant (K_(d)) was 38.46 nmol/L and IC_(50) was 6.353 nmol/L. Erythrocyte ~(86)Rb uptake experimentshowed that the RES2 derivative blocked the inhibitory effect of ouabain on the sodium pump on erythrocyte membrane in a dose-dependent manner. The results showed that the RES2 derivative is capable of binding to ouabain and improving the activity of sodiumpump on erythrocyte membrane, suggesting that the RES2 derivative might become an effective antihypertensive drug in the future.

Key words: sodium pump #alpha#2 subunit;extramembrane fragment;Ouabain;Hypertension

Received: 　　Accepted:

Corresponding author: 　　E-mail:

Citing This Article：

Zhang Mingjuan, Yang Jun, Qiang Lei, Wang Rong, Song Yafan, Niu Xiaolin. Activity identification of peptide containing rat sodium pump #alpha#2 subunit M1--M2 extramembrane fragment {sl in vitro}. Acta Physiol Sin 2008; 60 (2): 205-210 (in Chinese with English abstract).