[NF-kappaB expression in lung tissue of acute lung injury rat model and the influence by antioxidant N-acetylcysteine].

OBJECTIVE

To observe the NF-kappaB expression in the lung tissue of LPS-induced acute lung injury(ALI) rat model and the influence of N-acetylcysteine (NAC) on NF-kappaB expression.

METHODS

The expression of NF-kappaB in lung tissue in ALI rat model and the influence of NAC on NF-kappaB expression were detected by immunohistochemical (ABC) staining and Western blot.

RESULTS

There were a small amount of sporadic NF-kappaB cells in airway epithelium and interstitium in normal control group. In contrast, nuclear NF-kappaB expression-positive cells increased obviously in airway mucosa, lung interestium, alveolar cavity and vascular wall of ALI rats. NF-kappaB(+) cells were mainly airway mucosa epithelial cells, infiltrating inflammatory cells, alveolar epithelial cells, and vascular endothelial cells. The NF-kappaB expression-positive cells in NAC therapy group notably decreased compared with ALI group and control group(P<0.01). Western blot analysis showed that the expression of NF-kappaB was different at various time points, reaching the peak at 3 h and then decreased (P<0.01) after LPS induced lung injury.

CONCLUSIONS

In LPS induced acute lung injury rat model, the NF-kappaB nuclear expression increased obviously in airway mucosa, lung interestium and alveolar cavity. Most cells in lung tissue participated in the activation of NF-kappaB. NAC could alleviate inflammation by inhibiting activation of NF-kappaB.