CCK-8抗炎作用中DAG-PKC信号通路对cAMP-PKA信号通路的影响

Effects of DAG-PKC signaling pathway on cAMP-PKA signaling pathway in anti-inflammatory effects of CCK-8

目的探讨CCK-8抗炎作用中DAG-PKC信号通路对cAMP-PKA信号通路的影响。方法分离纯化大鼠PIMs,分别用LPS、CCK、LPS+CCK、PMA、SC-3088、LPS+PMA、LPS+SC-3088、CCK+PMA、CCK+SC-3088、LPS+CCK+PMA、LPS+CCK+SC-3088孵育一定时间,采用125I-cAMP放射免疫分析法测定细胞内cAMP含量,用放射激酶法测定PKA活性。结果单独应用PMA和SC-3088孵育大鼠PIMs,细胞内cAMP含量和PKA活性与正常对照组相比无明显变化(P>0.05)。PMA可升高LPS作用下的细胞内cAMP含量和PKA活性(P<0.01),SC-3088则可使LPS作用下的细胞内cAMP含量和PKA活性降低(P<0.01)。分别应用PMA、SC-3088与CCK共同孵育,则CCK+PMA组细胞内cAMP含量和PKA活性高于单独应用CCK组(P<0.01),CCK+SC-3088组则降低(P<0.01)。与LPS+CCK组相比,PMA+LPS+CCK组细胞内cAMP含量和PKA活性升高(P<0.01),而SC-3088+LPS+CCK组细胞内cAMP含量和PKA活性降低(P<0.01)。结论在LPS诱导的大鼠PIMs,CCK-8可通过激活cAMP-PKA信号通路发挥抗炎作用;DAG-PKC信号通路的活化对cAMP-PKA信号通路有正性调节作用。

Aim To investigate the effects of DAGPKC signaling pathway on cAMP-PKA signaling pathway in anti-inflammatory effects of CCK-8. Methods PIMs were isolated and purified, and stimulated with LPS or/and CCK-8 in absence or presence of PMA or SC-3088 for determinated time. ^125 I-cAMP radioimmunoassay was used to detect the cAMP content and radioenzymatic assay to detect the PKA activity. Results No change of cAMP content and PKA activity was found when respectively incubating PIMs with PMA and SC-3088 alone （P 〉 0. 05 ）. But PMA increased and SC-3088 decreased cAMP content and PKA activi- ty in LPS-stimulated rat PIMs （P 〈 0. 01 ）. Co-incubating PIMs with CCK-8 and PMA or SC-3088 resulted in increase and decrease of cAMP content and PKA activity respectively, compared with that of CCK-8 alone （P 〈 0. 01 ）. The cAMP content and PKA activity were significantly increased in PMA ＋ LPS ＋ CCK group, but decreased in SC-3088 ＋ LPS ＋ CCK in comparison with LPS ＋ CCK group （ P 〈 0.01 ）. Conclusions CCK-8 could exert anti-inflammatory effect by activating cAMP-PKA signaling pathway in LPS-stimulated rat PIMs, activation of DAG-PKC signaling pathway had positive regulation to cAMP-PKA signaling pathway.