【摘要】 目的：研究大鼠一次性游泳耐力运动1.5 h和3.0 h中补充不同大豆肽含量饮料对血清游离氨基酸（FAA）水平的影响。方法：110只Wistar大鼠随机分为11组，安静对照组（SC组）1组、运动对照组（EC组）2组和运动补充组（ES组）8组，每组10只。SC组不运动，EC组和ES组进行一次流动水游泳池耐力游泳运动。EC组2组大鼠分别运动1.5 h和3.0 h。ES组8组大鼠，其中4组运动1.5 h，另4组运动3.0 h。SC组和EC组以5%蔗糖饮料（CHO）灌胃，ES组分别以4个肽剂量组（0.07、0.13、0.27、0.53 g/kg·bw/h）（肽/糖比分别为0.3、0.6、1.2、2.4）的肽-糖饮料（P-CHO）灌胃，灌胃频率为1次/15 min,ES组运动1.5 h和3.0 h的大鼠分别灌胃6次和12次。运动后即刻取各组大鼠血样测定19种血清游离氨基酸（FAA）、血氨（NH3）、血尿酸氮（BUN）浓度。结果：（1）与SC组比，EC组血清缬氨酸（Val）、异亮氨酸（Ile）、亮氨酸（Leu）、酪氨酸（Tyr）、苯丙氨酸（Phe）、赖氨酸（Lys）、支链氨基酸（BCAA）和芳香族氨基酸（AAA）及其比值（BCAA/AAA）、碱性氨基酸（BAA）及BUN浓度显著增加，谷氨酸（Glu）、苏氨酸（Thr）浓度、色氨酸（Trp）/支链氨基酸（BCAA）比值显著下降；（2）与SC组比，ES组Val、Ile、Leu、Tyr、Phe、Lys、BCAA、AAA、BCAA/AAA、BAA以及BUN仍显著增加，此外牛磺酸（Tau）、精氨酸（Arg）、组氨酸（His）、必需氨基酸（EAA）、含硫氨基酸（SCAA）显著增加，Glu和Trp/BCAA比值仍下降；（3）ES组与EC组比，Ala、Ile、Tyr、Thr、Lys及EAA、BAA显著增加；（4）运动3.0 h与运动1.5 h比，Val、Tau及BCAA/AAA比值显著增加，而Ala、Tyr、脯氨酸（Pro）、Arg及AAA显著降低；（5）肽补充量0.53 g/kg·bw/h与0.07、0.13、0.27 g/kg·bw/h比，血清Ala、Glu、Val、Ile、Leu、Tyr、Thr、Pro、Gly、Arg、Lys、His及EAA、BCAA、AAA、BAA显著增加，而0.07、0.13、0.27 g/kg·bw/h间的差异无显著性。（6）肽补充量与FAA的量-效分析结果显示：与EC组比，ES组运动1.5 h后，Val、Ile、Leu、Tyr、Pro、Asp、Arg、Lys、BCAA、BAA、BUN随肽补充量增加，增幅大于20%；运动3.0 h后，Glu、Val、Ile、Tyr、Pro、Tau、Asp、Arg、Lys、BCAA、AAA、BAA随肽补充量增加，增幅大于20%；而Trp/BCAA降幅大于20%。结论：大鼠游泳耐力运动中持续规律补充以酶解大豆肽为原料配制的P-CHO，当肽补充量小于0.27 g/kg·bw/h时，可基本维持或增强大鼠运动1.5 h后多种血液FAA稳定，当运动1.5 h～3.0 h时，需要更大剂量的肽补充量（0.27～0.53 g/kg·bw/h）才能达到更高的血液FAA（尤其是BCAA）水平，同时降低Trp/BCAA，以满足运动中的物质和能量代谢需求，并可能有益于缓解运动中枢疲劳、减轻骨骼肌损伤。不同时长运动，随肽补充量增加，发生显著变化的单一FAA有所差别，值得进一步探讨。更多还原

【Abstract】 Objective To examine the effect of supplementing beverages with different soybean peptides on serum-free amino acid(FAA)levels during 1.5-hour and 3.0-hour one-time swimming endurance exercise of rats. Method One hundred and ten Wistar rats were randomly assigned into 11 groups of 10 subjects each,including 1 sedentary control group(SC),2 exercise control groups(EC),and 8exercise supplement groups(ES). Both EC and ES groups conducted the swimming endurance exercise in a flowing water swimming pool,while SC group did not. One half of EC and ES groups exercised for 1.5 h,while the other half did 3.0 h. SC and EC groups were given 5% sucrose beverage(CHO)by gavage. ES group was gavaged with peptide-sucrose beverage(P-CHO) of 4 peptide dose groups(0.07,0.13,0.27 and 0.53 g/kg·bw/h)(peptide/carbohydrate ratio:0.3,0.6,1.2,and 2.4) every 15minutes. Blood samples were collected immediately after exercise to determine the concentration of 19FAAs,blood ammonia(NH3) and blood urine nitrogen(BUN). Results(1) Compared with SC group,a significant increase was observed in the average serum levels of valine(Val),isoleucine(Ile),leucine(Leu),tyrosine(Tyr),phenylalanine(Phe),lysine(Lys),branched-chain amino acids(BCAA),aromatic amino acids(AAA),the BCAA to AAA ratio(BCAA/AAA),basic amino acids(BAA) and BUN of EC group,but a significant decrease in the average concentrations of glutamic acid(Glu),threonine(Thr) and tryptophan(Trp)/branched-chain amino acids(BCAA) ratio.(2) Compared with SC group,the average levels of Val,Ile,Leu,Tyr,Phe,Lys,BCAA,AAA,BCAA/AAA,BAA and BUN,as well as histidine(His),essential amino acids(EAA),and sulfur-containing amino acids(SCAA) increased significantly in ES group,while the average Glu level and Trp/BCAA ratio decreased significantly.(3) Compared with EC group,the concentration of Ala,Ile,Tyr,Thr,Lys,EAA and BAA increased significantly in ES group.(4) Compared with during the 1.5 h exercise,the average levels of Val,Tau and BCAA/AAA ratio increased significantly during the 3.0 h exercise,while those of Ala,Tyr,Proline(Pro),Arg and AAA decreased significantly.(5) The average level of Ala,Glu,Val,Ile,Leu,Tyr,Thr,Pro,Gly,Arg,Lys,His,EAA,BCAA,AAA and BAA increased significantly in rats with the ratio of peptide supplementation at 0.53 g/kg·bw/h,compared to those with0.07,0.13,0.27 g/kg·bw/h. However,no significant differences were found among those with the ratio of peptide supplementation at 0.07,0.13,and 0.27 g/kg·bw/h.(6) The results of dose-response analysis of the peptide supplementation and FAA levels showed that compared with EC group,after1.5 hours of exercise,the average Val,Ile,Leu,Tyr,Pro,Asp,Arg,Lys,BCAA,BAA and BUN of ES group,increased more than 20% with the increase in the peptide supplementation,while after3.0 hours of exercise,the average Glu,Val,Ile,Tyr,Pro,Tau,Asp,Arg,Lys,BCAA,AAA,and BAA levels increased more than 20% with the increase in peptide supplementation,and the Trp/BCAA ratio decrease by more than 20%. Conclusion For swimming-endurance-exercise rats with continuous and regular supplementation of P-CHO prepared with enzymatic hydrolyzed soybean peptide,when the amount of supplementation is less than 0.27 g/kg·bw/h,the stability of various FAAs can be basically maintained or increased after 1.5 h of exercise. When exercising for 1.5 h～3.0 h,a larger dose of peptide supplementation(0.27～0.53 g/kg·bw/h) is required to achieve higher levels of FAA(especially BCAA),and lower Trp/BCAA to meet the substance and energy metabolism requirements during exercise,which may be beneficial to relieve motor center fatigue and reduce skeletal muscle damage. For exercise with different duration,the fluctuation of different FAAs with the increase of peptide supplementation,deserves further investigation.更多还原