Nishihira T, Komatsu H, Sagawa J, Shineha R, Mori S
Second Department of Surgery, Tohoku University School of Medicine, Sendai, Japan.
JPEN J Parenter Enteral Nutr. 1995 May-Jun;19(3):199-203. doi: 10.1177/0148607195019003199.
Valine-depleted amino acid imbalance, while having a suppressive effect on tumor growth, may induce fatty liver.
We administered a valine-depleted total parenteral nutrition (TPN) solution by the central venous route to non-tumor-bearing rats and examined the time course of the development of fatty liver. In an attempt to prevent this condition, we administered a continuous infusion of low concentrations of valine via the portal vein simultaneously with administration of central venous valine-depleted nutrition for 4 days.
A marked accumulation of triglyceride was observed in the liver on day 4 of the administration of valine-depleted nutrition. It is speculated that such accumulation is the cause of fatty liver. The level of valine in the peripheral blood began to decrease soon after administration was begun and resulted in a state of systemic valine deficiency. Rats given 25% or more of the valine concentration in the standard TPN solution via the portal vein simultaneously with the administration of central venous valine-depleted nutrition, had a triglyceride level similar to that of the control group. The group given 50% or less of the valine concentration had a level of valine in the peripheral blood as low as that of the valine-depleted group, indicating the maintenance of a valine-deficient state.
Administration of low concentrations of valine via the portal vein simultaneous with central venous administration of valine-depleted TPN solution may prevent fatty liver.
缺乏缬氨酸的氨基酸失衡虽然对肿瘤生长有抑制作用,但可能会诱发脂肪肝。
我们通过中心静脉途径给无瘤大鼠输注缺乏缬氨酸的全胃肠外营养(TPN)溶液,并观察脂肪肝发展的时间进程。为了预防这种情况,我们在通过中心静脉给予缺乏缬氨酸的营养的同时,经门静脉持续输注低浓度缬氨酸,共4天。
在给予缺乏缬氨酸的营养的第4天,肝脏中观察到甘油三酯明显蓄积。据推测,这种蓄积是脂肪肝的原因。给药后外周血中的缬氨酸水平很快开始下降,导致全身缬氨酸缺乏状态。在通过中心静脉给予缺乏缬氨酸的营养的同时,经门静脉给予标准TPN溶液中25%或更多缬氨酸浓度的大鼠,其甘油三酯水平与对照组相似。给予50%或更低缬氨酸浓度的组外周血中的缬氨酸水平与缺乏缬氨酸的组一样低,表明维持了缬氨酸缺乏状态。
在经中心静脉给予缺乏缬氨酸的TPN溶液的同时经门静脉给予低浓度缬氨酸可能预防脂肪肝。