Objective   To study the effects of postweaning dietary compositions on hepatic CPT-I gene expression in rats.

  Methods   Male Wistar rats weaned on 24 d were randomly divided into A, B, C, D groups and were fed a high carbohydrate, high protein, high unsaturated fatty acid and high saturated fatty acid diet respectively.After three weeks, all rats were assigned to basic diet for 2 weeks, then rats from A group were randomly divided into groups A1 and A2.A1 was fed on basic diet continuously.Groups A 2, B, C, and D were assigned to high-fat diet for six weeks.Eightrats from each group were sacrificed at the end of experiment to detect body weight, body fat content and blood glucose level.RT-PCR were used to determine the expression of CPT-I in liver tissue.

  Results   Body weight, body fat and blood glucose level in C group were significantly lower than those in A2 on llw(P < 0.05).the body weight, body fat content in B group were significantly lower than that in A 2(P < 0.05).However, blood glucose level was higher than A2 on 1lw(P > 0.05).the body weight in D group was significantly lower than that in A2(P < 0.05), but body fat content and blood glucose levels were not significantly lower than A2 on 11w(P > 0.05).the CPT-I mRNA level in C group was persistently increased to be the highest among all groupsduring exper iment and higher than that of other groups at the end of the exper iment significantly.

  Conclusion   Feeding on high unsaturated-fatty acid diet after weaning may significantly inhibit the obesity occurance, improve the abnormal blood glucose level in rats fed with high-fat diet.Persistently increased CPT-I gene expression may be involved in inhibiting later obesity by early nutrition.