1.Department of Paediatrics, the Third Affiliated Hospital of Guangzhou Medical University, Guangdong, Guangzhou 510150, China; 2. Department of Paediatrics, the First Hospital of Changsha, Hunan, Changsha 410005, China
Abstract: Objective To explore the effects of high-protein supply for breast feeding rats on brain development of premature rats and its mechanism. Methods SPF class Sprague-Dawley rats were obtained; young rats of term group and premature group were all breastfed; maternal rats were given high-protein food or standard protein food during lactation. Young rats were divided into premature high protein group, premature standard protein group, term high protein group, term standard protein group,16 rats in each group. Rats of the experimental groups were given standard protein food from 22 days on end of lactation. Young rats were fed to 6 or 8 weeks, then Morris water maze of place navigation test was performed and escape latency was recorded. After place navigation test, the expression of mammalian target of rapamycin (mTOR) positive cells in the hippocampus of the brain was detected by immunohistochemistry. Statistical analysis was performed by variance analysis and t test. Results For the rats of 6 weeks, as training days extending, escape latency of rats of every group gradually shortened. On the fourth day, escape latency of premature standard protein group was higher than that of term standard protein group[(40.5±11.9) vs (28.3±10.2) s]; the number of mTOR positive cells of hippocampal CA1 area of premature standard protein group was lower than that of term standard protein group[(35.2±2.9) vs (45.7±6.5)](both P﹤0.05). Although escape latency of premature high protein group was lower than that of premature standard protein group, but there was no significant difference [(34.4±12.8) vs (40.5±11.9) s, P﹥0.05]. Comparison of escape latency of premature high protein group and term high protein group [(34.4±12.8) vs (28.1±16.4) s], the number of mTOR positive cells [(36.1±3.7) vs (39.4±1.7)], there was no significant difference (both P﹥0.05). For the rats of 8 weeks, on the fourth day, comparison of escape latency between premature high protein group and standard protein group [(29.6±13.5) vs (25.2±11.0) s], between premature high protein group and term high protein group [(29.6±13.5) vs (23.8±11.6) s], between premature standard protein group and term standard protein group[(25.2±11.0) vs (23.5±10.4) s], there was no significant difference (all P﹥0.05). Comparison of the number of mTOR positive cells, premature high protein group was lower than term high protein group[(36.9±3.6) vs (44.1±7.2)], premature standard protein group was lower than term standard protein group[(39.6±2.8) vs (53.0±5.9)] (both P﹤0.05); with same gestational age, there was no statistical difference between different groups (P > 0.05). Conclusion High-protein diet intervention of maternal rats during lactation has a positive effect on early learning ability of premature rats, but it may take a long time to accumulate for the impact of high-protein diet on learning ability of premature rats.
朱力逢 严彩满 王潜 等. 母鼠哺乳期高蛋白饮食对早产大鼠学习能力的影响及其机制[J]. 发育医学电子杂志, 2017, 5(4): 233-238.
ZHU Li-feng YAN Cai-man WANG Qian et al. Impact of high-protein diet for breast feeding rats on learning ability of premature rats and its mechanism. Journal of Developmental Medicine(Electronic Version), 2017, 5(4): 233-238.