不同剂量氢化可的松对内毒素休克早期大鼠内环境影响的实验研究

目的探讨不同剂量氢化可的松(hydrocortisone,HC)对内毒素休克早期大鼠内环境的影响。方法经股静脉注射脂多糖(lipopolysaccharide,LPS)25 mg/kg,建立内环境紊乱的内毒素休克早期大鼠模型。40只雄性Wistar大鼠随机分为对照组(等量生理盐水替代LPS和HC)、内毒素休克早期组(LPS组,等量生理盐水替代HC)、大剂量HC组(HD组,HC 100mg/kg)、中剂量HC组(MD组,HC 50 mg/kg)和小剂量HC组(LD组,HC 5 mg/kg),每组8只动物。模型建立后经静脉注射HC处理并观察4 h后,经股动脉取血进行微量血气、血糖及电解质钾、钠、钙的检测。结果与对照组相比,LPS组出现明显的代谢性酸中毒、高血钾、高血钠、低血钙及高血糖等内环境紊乱状态(P<0.05)。各HC干预组代谢性酸中毒指标及高血钾有所改善,以LD组改善最为显著(P<0.05)。仅LD组血钙明显高于LPS组(P=0.023),MD、HD组与LPS组相比差异无统计学意义。对照组与LD组的基础血糖值与实验结束时血糖值比较差异无统计学意义。实验结束时,LPS组血糖显著高于对照组和LD组(P<0.05);而HD组血糖甚至较LPS组高,MD组结果介于HD组与LD组之间,与HD组比较差异无统计学意义。结论内毒素休克早期大鼠存在明显的内环境紊乱,不同剂量HC对其影响不同。小剂量HC对早期内环境紊乱有所改善,大、中剂量HC对内毒素休克早期内环境紊乱未见明显改善。

Effects of Different Dosages of Hydrocortisone on Homeostasis in Rats at Early Stage of Endotoxic Shock

Objective To investigate the effects of different dosages of hydrocortisone(HC) on the disorder of homeostasis in rats at early stage of endotoxic shock.Methods The rat model of early endotoxic shock was induced by intraveneous injection of lipopolysaccharide(LPS,25 mg/kg) through femoral vein.40 male Wistar rats were randomly divided into the following 5 groups: control group(same volume of normal saline LPS and HC substitutes),LPS group(same volume of normal saline as HC substitute),high-dosage HC group(HD group,HC100 mg/kg),middle-dosage HC group(MD group,HC 50 mg/kg) and low-dosage HC group(LD group,HC 5 mg/kg).Four hours after the hydrocortisone treatment,the specimens were collected for blood gas analyses,as well as electrolytes and blood sugar concentrations detections. Results Metabolic acidosis,hyperkalemia,hypernatremia,hypocalcemia and hyperglycemia were observed in LPS group rats(P<0.05).After HC treatment,the metabolic acidosis and hyperkalemia were attenuated in different degrees,and the most significant improvements were found in LD group.Hypocalcemia and hyperglycemia were corrected significantly only in LD group((P<)(0.05)).High-dosage of HC may even aggravate hyperglycemia.The effects of middle-dosage HC is in-between LD and HD groups,and there was no significant difference between HD and MD groups,P>0.05.Conclusion Different dosages of HC had different effects on homeostasis in early endotoxic shock rats.Low dosage of HC may ameliorate the disorder of homeostasis in early endotoxic shock.High-dosage and middle-dose of HC had no significant improvement in the disorder of homeostasis.