目的　为探讨几丁聚糖 (chitosan)对大鼠体重的影响及其与体内瘦素和睾酮的关系。方法　给 5组大鼠分别喂饲基础饲料、高脂饲料和加不同剂量chitosan的高脂饲料共 7周。每周称 1次体重 ,于第 7周末断头取血 ,用放射免疫试剂盒检测血浆中瘦素和血清中睾酮。结果　chitosan具有明显抑制高脂饲料诱导大鼠肥胖和降低血中睾酮的作用 ;通过体重与瘦素变化规律的分析 ,推测chitosan可能对瘦素的分泌具有促进作用。结论　chitosan降低血中睾酮浓度 ,从而促进瘦素分泌 ,可能是chitosan抑制高脂饲料诱导大鼠脂胖的部分原因。 Objective To investigate the effect of chitosan on body weight in rats and its relationship with leptin and testosterone in vivo. Methods Five groups of rats were fed with basal diet, high-fat diet and high-fat diet with different doses of chitosan for 7 weeks respectively. Body weight was weighed weekly, decapitated at week 7, and leptin in plasma and testosterone in serum were detected by radioimmunoassay kit. Results Chitosan could inhibit the obesity and decrease the level of testosterone in rats induced by high-fat diet. Through the analysis of the changes of body weight and leptin, it was speculated that chitosan might promote the secretion of leptin. Conclusion Chitosan can reduce the level of serum testosterone and promote the secretion of leptin, which may be partly responsible for the inhibition of lipid-induced cholinesteration in rats by high-fat diet.