创伤后活化T细胞内cAMP代谢、蛋白激酶A活性的变化及意义

The Changes of cAMP Metabolism ,Protein Kinase A Activity in Activated T Cells after Trauma and Their Significance

研究了创伤小鼠活化Ｔ细胞内ｃＡＭＰ代谢、蛋白激酶Ａ（ＰＫＡ）活性的变化及同Ｔ细胞功能的关系。结果显示，创伤后活化Ｔ细胞内ｃＡＭＰ含量增加，这一变化同创伤后Ｔ细胞白介素２（ＩＬ－２）生成减少，ＩＬ－２受体（ＩＬ－２Ｒ）表达受抑，Ｔ淋巴细胞转化（ＴＬＴ）降低密切相关。创伤后活化Ｔ细胞内腺苷酸环化酶（ＡＣ）、ＰＫＡ活性增加，ｃＡＭＰ－磷酸二酯酶（ｃＡＭＰ－ＰＤＥ）活性降低。ＰＫＡ抑制剂Ｈ－８在体外可明显逆转创伤小鼠Ｔ细胞功能的受抑状态。提示ｃＡＭＰ－ＰＫＡ途径参与了创伤后Ｔ细胞功能的抑制过程。ＡＣ活性增加、ｃＡＭＰ－ＰＤＥ活性降低是导致Ｔ细胞内ｃＡＭＰ含量增加的原因。

he changes of cAMP metabolism ,protein kinaseA(PKA)activity in activated T cells andtheir relationship with T cells functions were studied in traumatized mice. The results showedthat the contents of cAMP in activated T cells were increased after trauma,and this change wasclosely related to reduced interleukin 2(IL-2)preduction, suppressed IL-2 receptor(IL-2R)ex-pression, decreased TIymphocytes transformation(TLT ) in T cells post trauma. Adenylate cy-clase(AC )and PKA activity in activated T cells were increased after trauma , while cAMP-phos-phediesterase(cAMP-PDE)activity was decreased.H 8,an inhibitor of PKA , can in vitro re-verse significantly suppressed T cells functions in traumatized mice . It is suggested that cAMP-PKA pathway participates in suppressive process of T cells functions after trauma. Increased ACactivity and decreased cAMP-PDE activity are causes resulting in elevated content of cAMP in Tcells.