大量维生素C对急性肺损伤的保护作用

目的观察大量维生素C(500mg/kg)对油酸诱导的家兔急性肺损伤的预防和治疗效果.方法30只家兔分4组,I组为对照组(CG);Ⅱ组为油酸组(OG);Ⅲ组为预防组(PG);Ⅳ组为治疗组(TG).于0、30、90和150 min采各组动物颈总动脉血测PaO2、超氧化物歧化酶(SOD)活力、血浆丙二醛(MDA).实验末右肺测湿质量,取支气管肺泡灌洗液(BALF)后烤箱烘干得湿干质量比值,留少许左肺标本甲醛固定做切片.结果油酸注入30 min后,PG组和TG组PaO2及SOD明显高于OG组(P＜0.01);而MDA明显低于OG组(P＜0.01).实验末PG组和TG组BALF中总蛋白、肺湿干质量比较OG组低(P＜0.05);肺组织病理切片显示损伤较轻.结论大量维生素C对油酸所致的家兔急性肺损伤,通过中和氧自由基,而发挥保护作用.

Study of preventive and therapeutic effects of large dose vitamin C on acute lung injury

[Objective] To investigate the preventive and therapeutic effect of large dose vitamin C on the acute lung injury model of rabbits induced by oleic acid. [Methods] A total of 30 rabbits were divided into four group randomly: control group (CG); oleic acid group (OG); preventive group (PG); treatment group(TG). Oxygen pressure in arterial blood (PaO2), superoxide dismutase (SOD) and malondialdehyde (MDA) in blood were measured in 0, 30, 90, 150 min respectively. All the animals were killed in 150 min later. Total protein in broncho-alveolar lavage fluid (BALF) and lung wet-dry weight ratio of the right lung was measured and the left lung sample was treated by formaldehyde and for pathological test. [Results] PaO2, SOD in PG group and TG group were significantly higher than that of OG group(P <0.01) and MDA significantly decreased (P <0.01) 30 min later after injected oleic acid; BALF and lung wet-dry weight ratio in PG group and TG group significantly decreased (P <0.05) than that of OG group; HE staining showed that the lung injury in PG group and TG group was improved. [Conclusions] A large dose vitamin C (500 mg/kg) has preventive effect on acute lung injury.