牛磺酸对维生素D_3和尼古丁诱导的大鼠钙化血管精氨酸/NO途径的影响

Taurine attenuates the vascular calcification and L-arginine/NO pathway impairement induced by vitamin D_3 and nicotine in rat

目的 观察钙化血管精氨酸 /NO途径的改变和外源性牛磺酸 (taurine,Tau)对血管钙化及精氨酸 /NO途径的影响。方法 维生素D3 (vitaminD3 ,VitD3 )肌注和尼古丁(nicotine ,Nic)灌胃制备大鼠血管钙化模型 ,检测血管钙含量和血管碱性磷酸酶 (ALP)活性、血浆精氨酸和亚硝酸盐(NO-2 )含量、血管环磷酸鸟苷 (cGMP)含量、血管一氧化氮合酶 (NOS)活性及血管精氨酸 (arginine ,Arg)转运。结果 钙化组 (VDN)大鼠血管钙含量较对照组升高 6 6倍 (P <0 0 1) ,血管ALP活性高 12 6倍 (P <0 0 1) ;血浆NO生成减少 ,血管cGMP水平降低 ,血管NOS活性增高 ,其中cNOS活性高 18 9% (P <0 0 1) ,但精氨酸转运在血管平滑肌和内皮明显减少 (- 6 3 8% ,- 5 5 2 % ,P <0 0 1)。口服牛磺酸治疗的大鼠较单纯VDN组 ,血管钙含量降低 4 9 5 % (P <0 0 1) ,血管ALP活性明显降低 ,血浆NO生成增加 ,血管cGMP含量增加 2 9 1% (P均 <0 0 1) ,血管精氨酸转运在血管平滑肌和内皮分别增加 79 4 %和 5 5 1% (P <0 0 1)。结论 给予外源性牛磺酸可以减轻VitD3 加Nic大鼠的血管钙化程度 ,改善钙化血管L Arg/NOS/NO/cGMP途径紊乱 ;

AIM To investigate the characteristics of L arginine/NO pathway in vascular calcification and the effect of administration of extraneous taurine on the metablism of arginine/NO pathway in vascular calcification. METHODS The vascular calcification model was produced by vitamin D 3 plus nicotine. Vascular calcium content, activity of alkaline phosphatase(ALP), plasma arginine and nitrite content, vascular cGMP, vascular NOS activity and arginine transport were measured. RESULTS The vascular calcium content and the ALP activity increased 6 6 times and 12 6 times in VDN rats( P <0 01), respectively compared with control group, and plasma NO production, vascular cGMP content were obviously decreased ( P <0 01), the activity of total NOS was increased, mainly increased constitutive NOS( P <0 01). However, the L arginine transport of vascular was obviously decreased ( P <0 01). After administrating taurine in VDN rats, the vascular calcium content and ALP activity were decreased ( P <0 01), the production of plasma NO and vascular cGMP content were increased ( P <0 01), and the L arginine transport of vascular smooth muscle and endothelia obviously enhanced (+79 4% and 55 1%, all P values <0 01), compared with VDN group. CONCLUSION Taurine may attenuate the vascular calcification and improve the disturbance of L arginine/NOS/NO/cGMP pathway in rats induced by Vit D 3 plus nicotine. Thus, it appears that there is a potential clinical value of protection and treatment in taurine to the vascular calcification of atherosclerosis and other cardiovascular diseases.