P物质的免疫调节作用

P物质在外周主要分布于了发出细传入的神经元内。在外周神经末梢释放的P物质参与免疫调节和炎症过程。P物质可以影响淋巴细胞的增殖、免疫球蛋白和细胞因子的合成，并能够调节辅佐细胞的活性和细胞因子的合成以及其他一些免疫细胞的活性。P物质通过以上作用参与调节细胞和体液免疫应答。在外周组织中，P物质能的神经纤维和一些免疫细胞联系密切，许多免疫细胞膜上存在有P物质的特异性受体。这些形态学资料为P物质参与免疫调节提供了证据。一些免疫细胞也能够产生P物质，并以自分泌或／和旁分泌的方式调节免疫细胞的功能。以上资料表明P物质不仅是一种神经肽，也是一种免疫调节因子，是神经系统和免疫系统共同的信使物质。

The Immune Regulatory Effects of Substance P

Substance P is mainly distributed in afferent neurons which give out fine axons in peripheral tissues. Substance P released from peripheral nerve endings participates in the process of immune regulation and inflammation. Substance P can influence the proliferation and the synthesis of immunoglobulin and cytokine of lymphocytes as well as regulate the activity and the synthesis of cytokine of accessory cells and other immunocyte. In peripheral tissues, substance P contributes to the humoral and cellular immunoresponse through the above effects. Substance P ergic nerve fibers closely contact with some immunocyte and there exist specific receptors in the membranes of many immunocytes. These morphological data provide evidences for substance P participating in the immune regulation process. Some immunocytes also can produce substance P, which acts as a paracrine or/and autocrine signal in the immunoregulation. All these indicate that substance P is not only a kind of neuropeptides but also a kind of immune regulators. Substance P is an important messenger in neuroimmune system.