探讨喂饲表达甲酰辅酶A转移酶（FCoAT）的大肠杆菌Nissle1917（EcN-Frc）对大鼠尿草酸浓度的影响。

将30只雄性SD大鼠随机分为六组（编号A-F），每组5只。除A组外，其余五组在食物中每克添加1%草酸。B组每次喂食前30 min，喂食1 ml EcN-Frc培养液，C、D、E、F组喂食1 ml EcN-Frc悬液（活细菌数10³）。C、D、E、F组喂饲细菌的方式分别为每日1次，每3 d一次，每周一次和观察期内首日喂养一次。实验周期为2周，分别于喂养当日，喂养后3、6、9、14 d分别记录大鼠健康情况和24 h尿草酸排泄量。

口服ECN-Frc能有效减低高草酸饮食大鼠的24 h尿草酸排泄量。含10³活菌数的EcN-Frc在喂养后3 d即可发挥作用。1次喂服10³个活菌数的ECN-Frc，2周后仍能有效降低大鼠尿中草酸浓度。所有大鼠观察期内均体健，未见明显异常。

低剂量口服EcN-Frc能有效降低高草酸饮食大鼠的24 h尿草酸排泄量，且安全，耐受性好。

To study of using E.coli Nissle1917 which can express FCoAT (EcN-Frc) as probiotic treatment to reduce urine oxalate in a rat model.

Thirty male SD rats were randomly divided into 6 groups (A to F). 1% oxalate was added to the diet for rats in group B, C, D, E, F; while rats in group A received regular diet. Furthermore, 30 minutes before each feeding, each rats in group B received 1 ml suspension, while those in group C, D, E, F was given 1 ml EcN-Frc suspension (10³ viable bacteria). Rats in group C, D, E, F were feeding bacteria every day, once every three days, once a week, respectively. 24-hour urine specimens were obtained on days 0, 3, 6, 9, 14 by placing the rats in metabolic cages.

Hyperoxaluria rats due to high dietary oxalate were treated by EcN-Frc. It can effectively reduce the high urinary oxalate level in rat model since day 3 after supplementation. The effect of the decrease proved directly proportional to the dose of EcN-Frc.But, one dose of EcN-Frc (10³ viable bacteria) can still effectively reduce urinary oxalate in a 2 weeks period. It showed that EcN-Frc had the ability to stay stable in rat’s intestine and grew well. In addition, during 2 weeks period, all rats kept health with no signs of toxicity.

Probiotic administration of low dose EcN-Frc can effectively reduce the high urinary oxalate in hyperoxaluria rats. EcN-Frc can stay stable in rat’s intestine and play a role in degrading oxalate. This approach appears to be safe and good tolerance.