Change of JNK and c-Jun in lung injury associated with paraquat poisoning of rats

Abstract

To investigate the change of JNK and c-Jun in lung injury associated with paraquat poisoning of rats. 46 Rats were randomly divided into four groups: PQ group (n = 12), control group (n = 10), PQ + ZnPP group (n = 12) and PQ + Hm group (n = 12). The rats were injected with 2% PQ (25 mg/kg, ip) in PQ group. ZnPP and Hemin (10 mg/kg, 10 mg/ml) were injected through inguinal vein before intraperitoneal administration of 2% paraquat in PQ + ZnPP group and PQ + Hm group respectively. The rats were injected NS (1 ml/kg, ip) in control group. HE dyeing of lung tissue and MDA content of plasma were used for estimating the injury of lung tissue. The content of CO in the lung tissue was determined. The expression of HO-1 mRNA of the lung tissue was detected by the reverse transcription-polymerase chain reaction. The phosphorylation of JNK and c-Jun was evaluated by Western blot analysis. The degree of lung injury in PQ group and PQ + ZnPP group was higher than that in control group and PQ + Hm group. But in PQ + Hm group the degree of lung injury was lower. The content of MDA in PQ group and PQ + ZnPP group was higher than that in control group and PQ + Hm group (P < 0.01). The content of MDA in PQ + Hm group was higher than that in control group (P < 0.05). The content of CO in lung tissue in PQ group, PQ + ZnPP group and PQ + Hm group was and (1.08 +/- 0.15 mg/L) respectively, and higher than that in control group (P < 0.01). The content of CO in lung tissue in PQ + Hm group was significantly higher than that in PQ + ZnPP group (P < 0.01). The expression of HO-1 and the phosphorylation of JNK (55.24 +/- 9.34, 38.15 +/- 10.71, 128.55 +/- 19.43) and c-Jun (23.16 +/- 4.85, 15.49 +/- 3.13, 44.89 +/- 10.37) were increased remarkably in PQ group, PQ + ZnPP group and PQ + Hm group. Those in PQ + Hm group were higher significantly than PQ group and PQ + ZnPP group (P < 0.01). Those in PQ + ZnPP group were lower than PQ group (P < 0.05). The increase of CO of lung tissue in rats at the lung injury associated with paraquat poisoning reduces the acute lung injury of rats. The level of JNK and c-Jun phosphorylation increases obviously, especially after Hemin is utilized.