Objective To investigate the gene expression of sodium pump α-subunit in aortic smooth muscle of 1-kidney-1-clip (1k1c) hypertensive rats. 　Methods 1k1c hypertensive rats were prepared by partially ligating the left renal artery and removing the right kidney. 4 weeks later, all the rats were killed and sodium pump α1- , α2-, and α3-subunit in aortic smooth muscles were detected with reverse transcription p ol ymerase chain reaction (RT-PCR) method and immunohistochemical assay at both mR NA and protein levels, respectively. 　Resulsts Changes in the expression of sodi um pump α-subunit gene were found in aortic smooth muscles of 1k1c hypertensiv e rats: α1-su bunit increased at both mRNA protein levels, while α2- and α3-subunits r emained without changes. 　Conclusions There were great changes in the gene expression of so dium pump α-subunit in aor tic smooth muscles of 1k1c hypertensive rats, which might be related to the development of hypertension in this hypertensive model.