美洛昔康对兔急性肺损伤受损心肌的保护作用

The protective effects of meloxicam on rabbit myocardium in acute lung injury

目的探讨美洛昔康对内毒素(ET)致急性肺损伤(ALI)兔心肌保护作用的机制。方法将24只日本大耳白兔随机分为对照组、ET致伤组、美洛昔康干预组。观测动脉血气,检测心肌血栓素B2(TXB2)、6-酮-前列腺素F1α(6-keto-PGF1α)和心脏型脂肪酸结合蛋白(H-FABP)的变化,并行心组织病理学观察。结果致伤组兔动脉血氧分压下降,心组织TXB2/6-keto-PGF1α比值高于对照组(分别为0.78±0.17vs0.59±0.09,P<0.05),H-FABP明显低于对照组(分别为132.57±46.91vs302.00±89.15,P<0.01),病理检查示局灶心肌细胞明显肿胀,有少量炎症细胞浸润。美洛昔康干预组动脉血氧分压未见明显下降,心肌TXB2/6-keto-PGF1α比值(0.66±0.13)介于对照组、致伤组两者之间,H-FABP高于致伤组(分别为229.63±88.00vs132.57±46.91,P<0.05),心肌病理检查示损伤轻于致伤组。结论美洛昔康可通过降低心肌组织中TXB2/6-keto-PGF1α比值,增加心肌H-FABP的含量,在一定程度上减轻内毒素肺损伤时对心脏的损伤作用。

Objective To explore the protective effects of meloxicam on rabbit myocardium in endotoxin（ ET） - induced acute lung injury（ALl）. Methods Twenty four Japanese flap - eared white rabbits were randomly assigned to three groups （ n = 8 per group ） ： control group , ET group and meloxicam ＋ ET group. ALI models were replicated with intravenous injection of ET （700 μg/kg）. In meloxicam ＋ ET group, meloxicam （2. 5 mg/kg） was intravenously injected 10 minutes before the administration of ET. In the process of this experiment, blood gas was measured at 0 h, 0. 5 h, 1h, 2h, 4h respectively. After 4 hours , the rabbits were killed by exsangninations. Thromboxane B2 （ TXB2 ） , 6 - keto - pros- taglandinF1α（6-keto- PGF1α）,heart- fatty acidbinding protein（ H- FABP ） were measured by radioimmunoassay. Pathological changes of myocardial tissues were examined with light microscrope. Results In ET group , arterial blood oxygen pressure（ PaO2 ） decreased, myocardial TXB2/6 -keto - PGF1α ratio was significantly higher than that in control group （ respectively 0. 78± 0. 17 vs 0. 59 ±0. 09 , P 〈 0.05） , the levels of myocardial H -FABP were significantly lower than those in control group（ respectively 132. 57 ±46. 91 vs 302.00 ±89. 15 P 〈0. 01 ）. Focal cadiocyte swelling and small amounts of inflammatory cell infiltration into myocardium were observed under light microscrope . In meloxicam ＋ ET group,PaO2 didn＇t markedly decreased , myocardial TXB2/6 -keto -PGF1α ratio （0. 66 ± 0. 13） was between control group and endotoxin - treated group. The levels of myocardial H - FABP in meloxicam ＋ ET group were significantly higher than those in ET group （ respectively 229. 63 ± 88. 00 vs 132. 57 ~ 46. 91 P 〈 0. 05 ）. Pathological examinations in meloxicam ＋ ET group were alleviated. Conclusion Meloxicam can down - regulate TXB2/6 - keto - PGF1α ratio and increase the levels myocardial of H - FABP , which posseses some myocardial protective effects on ALI induced by ET in rabbits.