大剂量氨溴索对百草枯中毒所致大鼠急性肺损伤的影响

目的探讨大剂量氨溴索对百草枯（PQ）中毒所致大鼠急性肺损伤的影响及其可能机制。方法136只大鼠随机分为对照组（24只）、氨溴索治疗组（治疗组，56只）和PQ染毒组（PQ组，56只）。对照组腹腔注射生理盐水1、25ml／kg，PQ组和治疗组均予腹腔注射体积分数为2％的PQ溶液25mg／kg，治疗组在PQ染毒后即刻腹腔注人含盐酸氨溴索（35mg／kg）的生理盐水溶液（1．25ml／kg），每日注射1次，分别在不同处理后第1、3、5和7天时处死大鼠。观察血液及肺泡灌洗液（BALF）中白细胞总数和中性粒细胞百分比的变化、BALF中蛋白含量、血浆和BALF中丙二醛（MDA）含量、超氧化物歧化酶（SOD）及谷胱甘肽过氧化物酶（GSH—Px）活力，并进行肺组织病理学检查及超微结构观察。结果PQ组血液及BALF中白细胞总数、蛋白含量明显高于对照组，差异均有统计学意义（P〈0.05或P〈0.01）；7d时PQ组血浆中MDA含量为（8．12±1．12）nmol／ml，明显高于对照组，GSH-Px活力为（1256．8±133．2）U／ml，明显低于对照组，差异均有统计学意义（P〈0．01）。治疗组血液及BALF中白细胞总数、蛋白含量明显低于PQ组，差异均有统计学意义（P〈0.05或P〈O．01）；7d时治疗组血浆中MDA含量为（4．86±0．75）nmol／ml，明显低于PQ组，GSH—Px活力[（1509．5±183．0）U／ml]及SOD活力[（3903．2±374、7）U／ml]，明显高于PQ组，差异均有统计学意义（P〈0．01）。光学显微镜及电子显微镜观察，应用大剂量氨溴索后肺组织损伤程度减轻。结论大剂量氨溴索可减轻PQ中毒所致大鼠急性肺损伤，在一定程度上能影响PQ中毒所致急性肺损伤的发生和发展。

Effects of high dose ambroxol on lung injury induced by paraquat in rats

OBJECTIVE: To evaluate the protective effect of high dose ambroxol, a mucoactive drug, on acute lung injury caused by paraquat in rats. METHODS: One hundred and thirty-six healthy male Sprague-Dawley rats were randomly divided into three groups: control group (n = 24) injected with normal saline intraperitoneally, PQ group (n = 56) [(2% paraquat (25 mg/kg) injected into peritoneal cavity on the first day)] and AT group (n = 56) ambroxol 35 mg/kg was injected into peritoneum daily after praraquat intoxication once daily for 7 consecutive days. The arterial gas was determined and the extent of lung injury was assessed by measuring the ratio of wet to dry weight (W/D) and protein content in BALF, the WBC count, the percentage of PMN, the content of malondialdehyde (MDA) and the levels of superoxide dismutase (SOD) in the blood and BALF respectively. Left lung tissue was observed through both light microscope and electron microscope (TEM). RESULTS: The white cell count and the content of protein in the blood and the BALF of PQ group were significantly higher than those of the control group (P < 0.05 or P < 0.01). On the 7th day, the content of MDA 9 [(8.12 +/- 1.12) nmol/ml] in the serum of PQ group was significantly higher than the control group and the GSH-Px activity [(1256.8 +/- 133.2) U/ml] was significantly lower than the control group (P < 0.01). The white cell count and the content of protein in the blood and the BALF of AT group were significantly lower than the PQ group (P < 0.05 or P < 0.01). On the 7th day, the content of MDA in the serum of the AT group [(4.86 +/- 0.75) nmol/ml] was significantly lower than the PQ group and the GSH-Px activity [(1509.5 +/- 183.0) U/ml] and the SOD activity [(3903.2 +/- 374.7) U/ml] were significantly higher than the PQ group (P < 0.01). Under optical and electronic microscopes, the injury of lung tissue was reduced after large dose of ambroxol was administered. CONCLUSION: Treatment with ambroxol (35 mg/kg) could influence the status of oxidative stress in lung and alleviate lung injury induced by paraquat. Ambroxol has obviously therapeutic effect on paraquat poisoning.