Effects of high protein feeding on brain's myelination and learning ability of intrauterine grow retardation in rats / 中华实用儿科临床杂志

ABSTRACT

Objective To explore the influence of 300 g/kg high protein diet on myelination of the intrauterine grow retardation (IUGR) in the rat brain and their learning and memory ability.Methods The pregnant rats were fed with 60 g/kg low protein diet.After birth,the offspring of IUGR group were fed separately by 300 g/kg high-protein diet (SH group) and 210 g/kg normal-protein diet(SC group).Forty newborn female pups,born from pregnant rats fed by normal-protein diet,were used as the control group(CC group).On the first,the 7th,the 15th and the 218t day,the body weight,brain weight of the offspring and their dynamics expressions of myelin basic protein(MBP) in corpus callosum,internal capsule and external capsule were observed with immunohistochemistry method.Morris water maze test was performed to assess learning and memory ability during the 26th-32ed,then the expression of MBP in the brain was observed.Results On the 21st day,the SH group gained catch-up growth weight,while the brain weight of them was still lower than that of the CC group (P ＜ 0.05),but higher than that of the SC group.At each time point,the MBP expression in corpus callosum,internal capsule and external capsule of SH group and SC group was lower than that of the CC group(all P ＜0.05),whereas the expression of myelin basic protein in the SH group was higher than that in SC group.The average latencies in all rats were reduced to some degree from the first to the 5th day.On the 5th day,there was no significantly difference between the SH group and CC group (P ＞ 0.05),while the escape latency was significantly shorter in rats of SH group than those of SC group (P ＜ 0.05).As far as search strategy was concerned,there was no difference in SH group and SC group of rats(P ＞ 0.05),but they performed better than those in the SC group on the 5th day(P ＜0.05).The frequency of passing through the platform quadrant was not significantly difference in rats among the 3 groups (P ＞ 0.05).Conclusions 300 g/kg high-protein diet on IUGR rats can increase brain weight and the expression of MBP,and improve the ability of learning to some extend.