创伤后2-氧-4-羧噻唑烷增强谷胱甘肽浓度的研究

Study on Possibility of Enhancing Concentration of GSH Supplement of L-2-Oxothiazolidine-4-Carboxylic Acid During Traumatic Status

目的探讨创伤时给予外源性左旋 - 2 -氧 - 4-羧噻唑烷 (OTZ)以增加机体谷胱甘肽 (GSH)合成的可能性 ,同时利用OTZ检测GSH的水平。 方法 7只实验兔创伤前后测定机体静息能耗 (REE) ;经颈静脉导管注入稳定同位素标记的13 C -OTZ后 ,在 12 0min内采集多个时段的血及呼出气体标本以测定血OTZ浓度及13 CO2 呼出速度 ;根据13 CO2 呼出速度曲线 ,计算出13 CO2 呼出的总量。 结果创伤前后REE分别为 2 0 5 99± 2 6 5 8J·kg-1·d-1,2 6 0 46± 45 98J·kg-1·d-1,创伤后明显增加 ;创伤后血13 C -OTZ浓度持续下降 ,尤以创伤后 30min内下降更为显著 ;创伤后 12 0min内13 CO2 呼出总量为 2 5 986 86 μmol/kg ,创伤前为 2 115 9 5 5 μmol/kg ,创伤后明显增多。 结论创伤时机体对半胱氨酸需求明显增加 ;外源性OTZ可能是创伤后补充半胱氨酸的一个重要来源 ;稳定同位素标记的13 C -OTZ可作为创伤前后GSH水平评估的检测手段。

Objective To enhance the synthesis of GSH by giving L-2-oxothiazolidine-4-carboxylic acid (OTZ) and use OTZ as indicators to evaluate the concentration of GSH during traumatic status. Methods 1. Measure rest energy expenditure (REE) in 7 rabbits before and after injury; 2. Measure the disappearance rate of 13 C-OTZ and appearance rate of 13 CO 2 in breath following a bolus injection of 13 C-OTZ tracer. Results 1. Injury resulted in a significantly ( P =0.0294) elevated REE (260.46±45.98 J·kg -1 ·d -1 vs 205.99±26.58 J·kg -1 ·d -1 ); 2. Injury resulted in a significantly decreased plasma 13 C-OTZ, especially within 30min; 3. Injury resulted in a significantly increased 13 CO 2 expiration (25986.86 μmol/kg vs 21159.55 μmol/kg). Conclusion 1. The demand of cysteine is henced after injury; 2. OTZ is an effective precursor of cysteine to meet such demand; 3. Increased 13 CO 2 expiration rate in breath after 13 C-OTZ injection may serve as a marker of a non-invasive test of the GSH status.