Krajcovicová-Kudlácková M, Dibák O
Vet Med (Praha). 1984 Oct;29(10):633-40.
Male rats of the Wistar strain, age 30, 75, 90 and 150 days, were given high-fat feeds (45%, 36.5%, 33% and 30%) ad libitum for 14 days. The net protein ratio (NPR), net protein utilization (NPU), and liver protein utilization (LPU) of the biological value of proteins were determined in comparison with diets considered as optimum for each age category. The specific activity of phosphoenol-pyruvate carboxykinase PEPCK (E.C..4.1.1.32) was measured in the liver of the animals. As demonstrated by the significantly reduced parameters of the biological value of proteins and the activated process of gluconeogenesis, a high intake of fats adversely affected the utilization of proteins in the organisms of 75 to 90 days old animals. The decrease in the NPR and NPU of the weanlings is insignificant; the increase in PEPCK is at the level of significance, which testifies to a good tolerance to the intake of fats by the animals after weaning, with respect to a similar composition of mothers' milk. In the animals with the slower growth and higher protein requirement for the maintenance of the organism (150 days old rats) the reduction of protein utilization and the increase in PEPCK activity as a result of a high fat intake are not so significant as in animals old 75 and 90 days. As suggested by the results, it is necessary to state another length of high-fat administration than 14 days.
选用30日龄、75日龄、90日龄和150日龄的雄性Wistar品系大鼠，随意给予高脂饲料（分别为45%、36.5%、33%和30%），持续14天。将蛋白质生物学价值的净蛋白比（NPR）、净蛋白利用率（NPU）和肝脏蛋白利用率（LPU）与各年龄组视为最佳的日粮进行比较测定。测定动物肝脏中磷酸烯醇丙酮酸羧激酶（PEPCK，E.C..4.1.1.32）的比活性。蛋白质生物学价值参数显著降低以及糖异生过程激活表明，高脂摄入对75至90日龄动物机体的蛋白质利用产生了不利影响。断奶幼鼠的NPR和NPU降低不显著；PEPCK升高具有显著性，这证明断奶后动物对脂肪摄入具有良好的耐受性，母乳成分与之相似。对于生长较慢且维持机体所需蛋白质需求较高的动物（150日龄大鼠），高脂肪摄入导致的蛋白质利用率降低和PEPCK活性升高不如75日龄和90日龄动物显著。结果表明，有必要说明高脂给药的时长不是14天。
