[Effect of different dietary protein source and protein level on serum lipids profile in rats]

The aim of this study was to evaluate the effect of dietary protein source and protein level on serum lipids in male rats.

Wistar weaning male rats were assigned to four groups (15 rats in each group) according to their original body weight. The effects of two kinds of dietary protein with two different levels, including low cow milk (LM, 9%), high cow milk (HM, 18%), low soybean and egg white (LS, 9%), and high soybean and egg white (HS, 18%) diets, were observed. Each group was provided with one of four diets for 20 weeks. Serum lipids were tested and the ratio of lipid were calculated.

Serum TC and HDL-C were the highest and TC/HDL-C was the lowest in HM group; serum TG in HS group was the lowest. The ratio of TG/HDL-C in HS and HM group was lower than LS and LM group. Compared with LM and HM groups, serum LDL-C and LDL-C/HDL-C was lower in LS and HS group.

Long-term intake of protein from soybean and egg white, serum TG level may be significantly lower, which may reduce the risk of atherosclerosis. There was a trend of rising serum cholesterol level in rats fed with protein from cow milk for a long time.