CCK-8 up-regulats signal pathway of LPS-induced HO-1 expression in rat lungs / 中国病理生理杂志

ABSTRACT

AIM: To study the signal pathway involved in up-regulation of LPS-induced HO-1 expression by CCK-8. METHODS: Forty-two SD rats were divided into 7 groups (six rats each) randomly as follows: control group, LPS group, LPS+SP600125 (JNK-specific inhibitor) group, CCK-8+LPS group, CCK-8+LPS+SP600125 group, CCK-8 group and CCK-8 +SP600125 group. Lungs from the rats in these 7 groups were excised 6 h after the agents were administered. HO-1 mRNA expression was examined by RT-PCR. The protein expression of HO-1 was detected by Western blotting and immunofluorescence flow cytometry (FCM). RESULTS: There were significant positive expression of HO-1 mRNA in LPS group compared to control group. CCK-8 enhanced LPS-induced HO-1 mRNA expression and CCK-8 alone induced HO-1 mRNA expression as well. The mRNA expressions of HO-1 in LPS group, CCK-8+LPS group and CCK-8 group were 3.01 (P<0.01), 5.88 (P<0.01) and 3.45 (P<0.01) times as many as that in control group, respectively. SP600125 inhibited the mRNA expression of HO-1 induced by CCK-8 and (or) LPS. The change of HO-1 protein expression was in accordance with that of HO-1 mRNA expression by Western blotting and immunofluorescence FCM. CONCLUSION: These results suggest that JNK/c-Jun signal pathway plays an important role in the up-regulation of LPS-induced HO-1 expression by CCK-8.