睾酮对人血管内皮细胞纤溶活性影响及机制

Effects of testosterone on the fibrinolysis activity of HUVEC and its mechanism

目的:观察睾酮对人血管内皮细胞分泌纤溶酶原激活物(tPA)、纤溶酶原激活物抑制物1(PAI- 1)的影响及其机制。方法:将体外培养的人血管内皮细胞(HUVEC)分为5个浓度睾酮组及单纯培养基对照组,MTT实验观察睾酮对细胞生长及活性影响。ELISA法测各组tPA、PAI - 1含量。用雄激素受体拮抗剂(flutamide)预处理细胞后重复实验。结果:生理及略低于生理剂量睾酮(3×10 -10 mol/L - 3×10 -8mol/L)可明显促进tPA分泌(P <0 . 0 1) ;而大剂量则使tPA含量明显减少(P <0 . 0 1)。各睾酮组PAI- 1含量均明显低于对照组(P <0 . 0 5 )。Flutamide能有效消除睾酮的上述作用。结论:生理浓度睾酮通过雄激素受体促进tPA分泌,降低PAI - 1浓度而增强纤溶系统活性,有利于防止血栓性疾病的发生。

AIM: To investigate the effect of testosterone with varied concentrations on the fibr inolysis activity of HUVEC and its mechanism. METHODS: Human umbilical vein endothelial cells (HUVEC) were cul tured as recommended. After confluence, the cultures were treated with testoster one(3 ×10 -10, 3×10 -9, 3×10 -8,3×10 -6, 3×10 -5 m ol/L) , and the control confluent cells were cultured in the same medium witho ut steroid. MTT experiment was repeated for 72 hours to investigate each groups' cell proliferation. The tPA and PAI-1 antigen levels were assayed with ELISA K its. Then with HUVEC incubated in androgen receptor antagonist (flutamide) 3 hou rs previously, the experiment was repeated. RESULTS: Testosterone at physiologic or lower concentrations (3 ×10 -10 to 3×10 -8 mol/L ) stimulated the secretion of tPA by HUVEC (P<0.01). However, tPA levels markedly reduced at larger doses (3 ×10 -6 to 3×10 -5 mol/L). On the other hand, PAI-1 antigen levels decrea sed significantly at the testosterone concentrations ranging from 3 ×10 -10 to 3×10 -5 mol/L (P<0.05). Flutamide attenuated the testosteron e's effects (P<0.05). CONCLUSIONS: The results indicated that testosterone at physiolo g ically relevant concentrations decreased PAI-1, while increased tPA levels via the androgen receptor, which suggested that testosterone may have beneficial eff ects on preventing thrombotic diseases.