When reducing external Na+ the contraction of NE was increased in thoracic aortic rings of both WKY and RH rats, but the degree of this increase was much lower in RH (8.3%) compared with WKY rats(18.1%), and the difference was statistically significant;

• 当减少Na~+浓度梯度时：即减少胞外Na~+浓度，无论WKY(Wister-Kyoto normotensive)还是RH(Renal hypertension)，去甲肾上腺素引起大鼠离体胸主动脉环的收缩幅度均增高，但RH组增高幅度(8.；3%25)较WKY组增高幅度(18