目的 探讨循环CD34⁺ 细胞水平与老年高血压关系，分析Ang-1/Tie-2 在内皮祖细胞的表达及其调控意义。方法 选择老年高血压患者59例为高血压组，正常健康者59例为对照组。RT-PCR法检测Ang-1/Tie-2 mRNA表达，应用流式细胞仪测定外周血CD34^+/PMNC值。分析外周血CD34^+/PMNC值与各临床指标的相关性，以及Ang-1和Tie-2 mRNA水平与CD34⁺/PMNC值的相关性。结果 高血压组外周血CD34⁺/PMNC值显著低于对照组（P=0.000）。高血压组外周血CD34⁺/PMNC值与收缩压呈负相关（r=-0.622,P=0.009），与舒张压、总胆固醇、三酰甘油、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、空腹血糖、尿酸水平无相关性。高血压组内皮祖细胞Ang-1和Tie-2 mRNA水平显著低于对照组（P=0.000），与CD34⁺/PMNC值分别呈正相关（r=0.561,P=0.005；r=0.473,P=0.009）。结论 老年高血压患者的心血管病变可能与Ang-1和Tie-2水平的下调从而影响内皮祖细胞的修复功能有关。

Objective To explore the correlation between circulating CD34⁺ cell level and elderly patients with hypertension and analyze Ang-1/Tie-2 expression in endothelial progenitor cells and its regulatory meaning. Methods Fiftynine elderly patients with hypertension and 59 healthy people were enrolled and assigned to the hypertension group and the control group, respectively. The mRNA level of Ang-1/Tie-2  was measured by RTPCR. Flow cytometry was used to detect the CD34⁺/PMNC value in peripheral blood. The correlations between CD34⁺/PMNC value in peripheral blood and clinical indexes and between Ang-1 and Tie-2  mRNA levels and CD34⁺/PMNC value were analyzed. Results The CD34⁺/PMNC value in peripheral blood of the hypertension group was significantly lower than that of the control group (P=0.000). The CD34⁺/PMNC value in peripheral blood of the hypertension group was negatively correlated to systolic pressure (r=-0.622; P=0.009), while was not correlated to diastolic pressure, total cholesterol, triglyceride, high density lipoprotein cholesterol, low density lipoprotein cholesterol levels, fasting blood glucose and uric acid. The Ang-1 and Tie-2 mRNA levels in endothelial progenitor cells of the hypertension group were significantly lower than those in the control group (P=0.000) and were positively correlated to CD34+/PMNC value （r=0.561,P=0.005；r=0.473,P=0.009）. Conclusion Cardiovascular lesions in elderly patients with hypertension may be associated with the downregulation of Ang-1 and Tie-2 levels, which affects repair function of endothelial progenitor cells.