关键词: 嗜酸粒细胞;P物质;哮喘

    摘 要:目的 探讨P物质(SP)在嗜酸粒细胞(Eos)活化中的作用及机制. 方法 以非连续性Percoll密度梯度分离法分离哮喘患者外周血Eos，了解SP对Eos过氧化物酶(EPO)活性和脱颗粒的调节作用，并以苔盼蓝拒染法评价SP对Eos存活时间的影响.用改良Boyden法，测定SP对Eos的趋化活性，并观察血小板激活因子(PAF)对SP预处理Eos的趋化作用. 结果 SP能显著增强EPO活性，刺激Eos脱颗粒，且与PAF有协同性，但不能延长Eos的存活时间.神经激肽-1(NK1)受体拮抗剂GR71251和磷酯酶C(PLC)抑制剂新霉素能阻断SP的上述作用.SP对Eos有显著趋化作用，其EC50为1×10-14 ～1×10-12 mol·L-1 ，最大趋化浓度为1×10-10 mol·L-1 ，此后随浓度的增加，其趋化作用降低.PAF对Eos的趋化作用因SP预处理Eos而显著强化(P<0.01)，NK1受体拮抗剂GR71251对SP的预处理作用有显著的阻断效应. 结论 SP作用于Eos胞膜上的NK1受体，经百日咳杆菌毒素(PTX)敏感型G蛋白，活化磷酯酶C从而激活Eos.同时SP还是一种Eos的趋化介质，与PAF有协同作用，NK1受体介导了这一协同效应.

    Effect of substance P on the activation and chemo┐taxis of eosinophils from asthmatic subjects

    WU Chang-Gui LIAO Jian-Jun MAO Bao-Ling SUN Bin

    1 Department of Respiratory Disease，Xijing Hospi-tal，Fourth Military Medical University，Xi'an710033，China，

    2 Institute of Respiratory Disease，Xinqiao Hospital，Third Military Medical University

    Keywords:eosinophils;substance P;asthma

    Abstract:AIM To investigate the effect of substance P(SP)on the activation of eosinophils(Eos).METHODS Eos were collected from peripheral blood of asthmatic sub-jects using a discontinuous Percoll density gradients.The ef-fect of SP on the activation of Eos was evaluated by measur-ing the activity of eosinophil peroxidase(EPO)in Eos and de-granulation of Eos.Effect of SP on the survival of Eos was e-valuated by typan blue dye exclusion.Induced chemotaxis by SP and platelet-activating factor(PAF)was assayed by a modified Boyden's chamber technique.Induced chemotaxis of pre-treated Eos with SP by PAF was also evaluated in the present study.RESULTS SP could enhance the activity of EPO and stimulate the degranulation of Eos significantly.In the present study ......