去甲肾上腺素对T淋巴细胞增殖的影响

EFFECT OF NORADRENALINEON TLYMPHOCYTE PROLIFERATION

本实验研究了不同浓度和不同作用时间的去甲肾上腺素（ＮＡ）对大鼠脾脏Ｔ淋巴细胞增殖的影响，并探讨α和β受体在此影响中的作用。结果表明，１０￣（－８）－－１０￣（－５）ｍｏｌ／ＬＮＡ可显著抑制由刀豆素Ａ（ＣｏｎＡ）诱导的Ｔ细胞增殖反应，其中１０￣（－７）ｍｏｌ／ＬＮＡ的抑制作用最强。ＮＡ与已被ＣｏｎＡ刺激ｌｈ的Ｔ细胞作用后，或者ＮＡ与脾细胞作用１ｈ后被洗去，Ｔ细胞的增殖仍受到抑制，但是ＮＡ不能抑制已被Ｃｏｎ Ａ刺激６ｈ的Ｔ细胞的增殖。α受体拮抗剂酚妥拉明（Ｐｈｅｎ，１０￣（－６）ｍｏｌ／Ｌ）和β受体拮抗剂心得安（Ｐｒｏｐ，１０￣（－７）ｍｏｌ／Ｌ）均可完全阻断１０￣（－８）和１０￣（－７）ｍｏｌ／ＬＮＡ的免疫抑制作用。结果提示，ＮＡ具有非浓度依赖性的细胞免疫抑制作用，此作用可能发生于Ｔ细胞激活前或激活早期，并可能通过α和β受体介导。

The effect of noradrenaline(NA)on spleen T lymphocyte proliferation induced byconcanavalin(Con A) was studied with the aid of MTT colorimetric assay.The proliferation of Tcells did not change when T cells were incubated simultaneously with 10￣-(10)or 10-(9)mol/L NAand Con A. However, NA at 10(-8)to 10(-5)mol/L dose range significantly inhibited theproliferation of T cells induced by Con A and the strongest inhibition occurred at 10￣(-7)mol/LNA. The T cell proliferation still decreased when NA(10￣(-8)to 10￣(-6)mol/L) was added to T cellshaving stimulated by Con A for an hour and incubated for 72 hours or when NA was washed offafter one-hour incubation with T Cells which were then incubated with Con A for 72 hours,butthe T cell proliferation did not change when NA was added to Tcells having incubated with ConAfor 6 hours.The NA(10￣(-8)or 10￣ (-7)mol/L)suppression ofTcell proliferation could be blockedby either α-adrenergic antagonist phentolamine orβ-adrenergic antagonist propranolol.It issuggested that NA can cause concentration-independent inhibition of T cell proliferation,andthe inhibitory effect of NA may occur either befor activation of T cells or just after stimulationof T cells by Con A and may be mediated by α-and β-adrenergic receptors.