目的 研究肉苁蓉多糖（polysaccharides of Cistanche deserticola，PCD）对亚急性衰老小鼠组织丙二醛（MDA）含量、端粒酶活性和免疫功能的影响。方法 使用D-半乳糖造成小鼠亚急性衰老模型。硫代巴比妥酸比色法检测MDA含量；PCR-ELISA法检测端粒酶活性；MTT法测定淋巴细胞增殖反应；中性红实验测定小鼠腹腔巨噬细胞吞噬功能；酶联免疫吸附试验（ELISA）法测定血清中IL-2含量。结果 模型组小鼠心、肝和脑MDA含量明显增加，端粒酶活性、淋巴细胞增殖反应、腹腔巨噬细胞吞噬功能和外周血IL-2含量均显著下降。给予PCD后，小鼠心、肝和脑MDA含量明显降低，心和脑组织端粒酶活性，淋巴细胞增殖反应、腹腔巨噬细胞吞噬功能和外周血IL-2含量明显升高。结论 PCD能拮抗自由基损伤，增强衰老小鼠心和脑组织端粒酶活性和机体免疫功能，对D-半乳糖所致的衰老有一定的改善作用。

OBJECTIVE To study the effect of polysaccharides of cistanche deserticola(PCD) on tissue malondialdehyde (MDA) content and telomerase activity and immune function of experimentally aging model mice. METHODS Subacute aging model mice were induced by D-galactose. The MDA content and telomerase activity were measured with thiobarbituric acid colorimetric method and PCR-ELISA， respectively. The lymphocyte proliferation was measured by MTT method. Phagocytosis of peritoneal macrophages was tested by neutral red test.The interleukin-2(IL-2) content in peripheral blood was measured by ELISA method. RESULTS In model group，MDA content was significantly increased in heart，liver and brain，telomerase activity，lymphocyte proliferation，phagocytosis of peritoneal macrophages and blood IL-2 content were obviously decreased.After treatment with PCD，MDA content was significantly decreased in heart，liver and brain.The telomerase activity in heart and brain，lymphocyte proliferation，phagocytosis of peritoneal macrophages and peripheral blood IL-2 content were obviously enhanced. CONCLUSION PCD can prevent aging of mice induced by D-galactose，which may be related to antagonize the free radical injury and enhance the immunity of aging mice.