目的·研究番泻苷A（sennoside A，SA）对2型糖尿病（diabetes mellitus type 2，T2DM）小鼠动脉粥样硬化斑块形成和5-羟色胺（5-hydroxytryptamine，5-HT）及其受体表达的影响。方法·将载脂蛋白E基因敲除小鼠12只随机分为模型组（model组）和治疗组（model+SA组），每组6只，同遗传背景C57BL/6J小鼠6只作为对照组（control组）。Control组普通饲养，model组和model+SA组在高脂饲养基础上每日给予腹腔注射30 mg/kg链脲佐菌素（streptozotocin，STZ）建立T2DM模型。Model+SA组每日给予SA（45 mg/kg）灌胃干预8周，control组和model组给予等体积双蒸水灌胃。比较造模及治疗前后小鼠体质量、空腹血糖和餐后2 h血糖情况，采用油红O染色和苏木精-伊红染色（hematoxylin-eosin staining，H-E染色）观察小鼠主动脉斑块面积，并用ELISA试剂盒测定小鼠血清和胸主动脉中5-HT水平，采用蛋白质印迹法（Western blotting）检测小鼠胸主动脉中5-羟色胺2B受体（5-hydroxytryptamine receptor 2B，HTR2B）和5-羟色胺转运蛋白（serotonin transporter，SERT）的表达情况。结果·与control组相比，model组小鼠体质量、空腹血糖和餐后2 h血糖均升高，糖代谢紊乱；主动脉斑块形成，胸主动脉中HTR2B、SERT蛋白表达升高；胸主动脉5-HT浓度降低，血清5-HT浓度升高（均P<0.05）。给予SA治疗后，与model组相比，model+SA组小鼠体质量下降，空腹血糖和餐后2 h血糖水平明显改善；主动脉斑块面积减少，胸主动脉HTR2B、SERT蛋白表达显著降低；胸主动脉5-HT浓度升高，血清5-HT浓度降低（均P<0.05）。结论·SA可减少T2DM小鼠动脉粥样硬化斑块面积，其作用可能与降低血糖、抑制5-HT及其受体表达有关。

Objective ·To investigate the effects of sennoside A (SA) on the formation of atherosclerotic plaque and the expression of 5-hydroxytryptamine (5-HT) and its receptor in mice with diabetes mellitus type 2 (T2DM). Methods ·Twelve mice with knocked-out apolipoprotein E gene were randomly divided into two groups, namely the model group and the model+SA group, with six mice in each group. Six C57BL/6J mice with the same genetic background were used as the control group. The control group was fed with normal diet, and the model group and the model+SA group were given intraperitoneal injection of streptozotocin (30 mg/kg) daily on the basis of high-fat diet to establish a model of T2DM. The model+SA group was given SA daily by gavage for 8 weeks, and the control group and the model group were given equal volume of distillation-distillation H₂O by gavage. The body weight, fasting blood glucose (FBG) and 2-h postprandial blood glucose of mice were compared before and after modeling and treatment. The area of aortic plaque was observed by oil red O staining and hematoxylin-eosin (H-E) staining, and the level of 5-HT in serum and thoracic aorta was measured by ELISA kit. Western blotting was used to detect the expression of 5-hydroxytryptamine receptor 2B (HTR2B) and serotonin transporter (SERT) in thoracic aorta of mice. Results ·Compared with the control group, the body weight, FBG and 2-h postprandial blood glucose in the model group increased, and glucose metabolism was disordered. The expression of HTR2B and SERT protein in thoracic aorta increased, while the concentration of 5-HT in thoracic aorta decreased. The serum 5-HT concentration increased (all P<0.05). After treatment with SA, compared with the model group, the body weight of the model+SA group decreased, and FBG and 2-h postprandial blood glucose were significantly improved. The area of aortic plaque and the expression of HTR2B and SERT protein in thoracic aorta significantly decreased, while the concentration of 5-HT increased. The serum 5-HT concentration decreased (all P<0.05). Conclusion ·SA can reduce atherosclerotic plaque area in T2DM mice, which may be related to lowering blood glucose and inhibiting the expression of 5-HT and its receptor.