5-羟色胺对巨核系造血的影响

Effect of 5-Hydroxtryptamine on Megakaryocytopoiesis ——Review

5-羟色胺(5-HT)是一种细胞生长因子,主要结合到细胞表面的5-HT1受体、5-HT2受体,通过Ras、MAPK通路促进多种细胞的增殖。在巨核系造血的早期,5-HT通过5-HT2B受体促进造血干细胞及巨核系祖细胞增殖和分化,其具体机制尚未十分清楚;在巨核系造血晚期,5-HT与5-HT2A受体结合促进一氧化氮合成,可能对血小板的释放有一定的影响。另外,5-HT能够对抗血小板α颗粒内容物血小板反应蛋白-1(TPS-1)所引起的巨核细胞凋亡,协同另一内容物血小板源性生长因子(PDGF)引起的巨核细胞增殖,因此5-HT可能是血小板反馈调节中比较重要的物质。本文就5HT及其受体、5HT是细胞生长因子、5HT促进细胞增殖的途径及5HT对巨核系祖细胞的影响进行了综述。

5-hydroxtryptamine （5-HT, serotonin） has been recognized not only as a neurotransmitter and vasoactive agent, but also as a growth factor, 5-HT mainly binds to 5-HT2 receptors or 5-HT1 receptors on cell surface to stimulate cell proliferation through Ras or MAPK pathway in many cell types, It has been reported that 5-HT stimulates megakaryoeytopoiesis v/a 5-HT receptors, The possible mechanism of 5-HT on the proliferation and differentiation of megakaryoeytes （MK） has been discussed in this review article. In early stage of megakaryoeytopoiesis, 5-HT may bind to 5-HT2B receptor on megakaryoeytes, and promotes their proliferation and differentiation. In the late stage, 5-HT may involve in the platelet release procedure by inducing nitric oxide （NO） synthesis via 5-HT2A receptors, 5-HT can also antagonize the apoptotic effect induced by thrombospondin-1 （ TSP-1 ） which is a platelet α granule protein and has synergic effect with platelet-derived growth factor （PDGF） to enhance megakaryoeytes proliferation. Therefore, 5-HT is likely to be an important substance in the feedback regulation of thrombopoiesis, In this review the 5-HT and its receptors, 5-HT as cell growth factor, pathway of 5-HT stimulating cell proliferation and influance of 5-HT on MK- progenitor cells were summarized.