本试验研究了N-乙酰半胱氨酸（NAC）对脂多糖（LPS）刺激仔猪肌肉能量状况的影响。选取18头杜洛克×长白×大白健康仔猪，体重（11.58±0.26） kg，随机分成3个处理（对照组、LPS组和NAC组），每个处理6个重复，每个重复1头猪。对照组和LPS组饲喂基础饲粮，NAC组饲喂基础饲粮+500 mg/kg NAC，LPS组和NAC组仔猪分别于试验的第10、13、20 天腹膜注射100 μg/kg BW的LPS，对照组注射等量的灭菌生理盐水。第21 天仔猪麻醉后进行屠宰，取腓肠肌待测。试验结果显示：1）饲粮中添加NAC缓解了LPS刺激导致的肌肉三磷酸腺苷（ATP）、腺苷酸池（TAN）和能荷（EC）水平（P＜0.05）的降低及一磷酸腺苷（AMP）水平和AMP/ATP比值的升高（P＜0.05）；2）饲粮中添加NAC显著缓解了LPS刺激引起的磷酸化的AMP激活蛋白激酶（pAMPK）与AMP激活蛋白激酶（AMPK）比值的升高（P<0.05）；3）饲粮中添加NAC显著缓解了LPS刺激引起的热休克蛋白70（HSP70）水平的升高（P<0.05）。由此可见，在本试验条件下，饲粮中添加500 mg/kg NAC可缓解LPS刺激导致的肌肉AMP和AMP/ATP的升高及ATP、TAN和EC的升高，缓解LPS刺激引起的肌肉能量过度损耗；饲粮中添加500 mg/kg NAC可能通过抑制AMPK磷酸化，对肌肉的能量状况产生影响。

Abstract: The aim of the current study was to evaluate the effects of supplementation with N-acetylcysteine （NAC） in the diet on muscle energy metabolism in piglets challenged with lipopolysaccharide (LPS). Eighteen healthy piglets ［Duroc×Landrace×Large white, (11.58±0.26) kg BW］ were randomly allocated to 3 treatments (control group, LPS group and NAC group). Each treatment included 6 replicates with one piglet per replicate. The piglets in the control group and LPS group were fed a basal diet, while the NAC group was fed the basal diet supplemented with 500 mg/kg NAC. On d 10, 13, 14 and 20, the piglets in the LPS group and NAC group were injected intraperitoneally with 100 μg/kg BW LPS, and the piglets in the control group were injected intraperitoneally with the same dose of physiological saline. On d 21, all the pigs were sacrificed to collect gastrocnemius for analysis. The results showed as follows: 1) dietary NAC attenuated the decrease of ATP, total adenine nucleotide (TAN) and energy charge (EC)(P<0.05), while it attenuated the increase of AMP level and AMP/ATP induced by LPS challenge significantly (P<0.05). 2) Dietary NAC attenuated the increase of pAMPK/AMPK induced by LPS challenge (P<0.05). 3) Dietary NAC attenuated the increase of the expression of HSP70 induced by LPS challenge (P<0.05). The results indicate that supplementation with 500 mg/kg NAC in the diet could attenuate the increase of AMP level and AMP/ATP, as well as the decrease of ATP, TAN and EC from LPS challenge. NAC may improve muscle energy status via inhibiting the phosphorylation of AMPK.［Chinese Journal of Animal Nutrition，2011，23（4）：615 -621］