Protective Effect Of Oxymatrine On Acute Lung Injury

Acute lung injury (ALI) and its more severe form, the acute respiratory distress syndrome (ARDS), are syndromes of acute respiratory failure that result from acute pulmonary edema and inflammation. The pathogenesis of them is not well known and clinically they have high mortality and no effective cure has been established. In this study, several ALI/ARDS animal models have been attempted to establish and the possible effect and mechanism of oxymatrine(OMT) on ALI/ARDS has been studied.1. Attempt to establish and evaluate Endotoxemia ALI/ARDS modelMice were injected with lipopolysaccharide(LPS) at the dose of 5 mg/kg via vena caudalis. Only mild pulmonary inflammatory reaction and little harm to lung tissue had been found ,which show the failure to establish ALI/ARDS model.2. Effect of OMT on ALI induced by oleic acid(OA) in ratsRats were administrated intraperitoneally with OMT before receiving injection with OA. Pretreatment of OMT significantly alleviated OA-induced lung injury accompanied by improvement of lung function, reduction of lung wet to dry weight ratio and decrease in serum TNF-a with the inhibition ratio of 19.9%, 30.9%(P<0.05), 43.9%(P<0.01) in 30mg.kg-1, 60mg.kg-1, 90mg.kg-l dosing OMT group, respectively. OMT has a dose-dependent beneficial effect on acute lung injury induced by oleic acid in rats. Its ability to suppress the TNF-a level in serum may contribute to the protection.3. Effect of OMT on activation of NF-κB in LPS-stimulated rat alveolar macrophage Rat alveolar macrophages were stimulated with LPS. Pretreatment with OMTsignificantly decrease the synthesis of TNF-a. However, OMT had no effect on the activation of NF-κB induced by LPS, which shows NF-κB is not involved in the inhibitory effect of OMT on TNF-α.In conclusion, our studies suggested that OMT has a dose-dependent beneficial effect on acute lung injury induced by oleic acid in rats, which is associated with its inhibitory effect on the synthesis of TNF-α . However, OMT shows no effect on the activity of NF-κB induced by LPS in vitro, which shows NF-κB is not involved in the inhibitory...