探讨外源性三碘甲状腺原氨酸（T₃）对小鼠肝脏增生的影响。

健康SPF级雌性C57BL/6小鼠45只，按随机数字表法随机分为A组、B组和对照组，每组15只。A、B组小鼠分别按每公斤体重10、5 μg经腹腔内注射外源性T₃ 2 ml，对照组注射生理盐水2 ml。3组分别于处理后0、7、14、21、42 d时各处死3只小鼠。处死后测量小鼠全肝脏重量。采用免疫组织化学方法检测肝细胞增殖情况。实验数据间比较采用t检验或方差分析。

与对照组相比，处理后7、14、21、42 d A组的肝脏重量明显增加（t=3.298，6.760，7.119，6.128；P<0.05），处理后14、21、42 d B组的肝脏重量明显增加（t=4.188，4.570，2.978；P<0.05）。处理后7、14、21、42 d A组增加的肝脏重量均比B组明显多（t=4.935，4.303，4.033，4.480；P<0.05）。其中处理后21 d，A、B组的肝脏重量增加至高峰（F=21.480，11.244；P<0.05）。与对照组相比，处理后0、7、14、21、42 d A组肝细胞数明显增加（t=28.383，23.842，40.194，31.059，15.841；P<0.05），B组的肝细胞数也明显增加（t=9.097，7.680，20.597，42.192，14.415；P<0.05）；且A组增加的肝细胞数均比B组明显多（t=8.016，4.872，10.719，9.514，7.831；P<0.05）。其中处理后14 d，A组的肝细胞数增加至高峰（F=169.190，P<0.05）；处理后21 d，B组的肝细胞数增加至高峰（F=90.460，P<0.05）。处理后A、B组肝细胞均发生广泛性增殖。

外源性T₃可有效促进小鼠肝脏增生，随着T₃浓度的升高，增生更为明显。

To investigate the impact of exogenous of triiodothyronine (T₃) on the liver hyperplasia of mouse.

Forty-five healthy specific pathogen free (SPF) C57BL/6 mice were divided into group A, B and control group using random number table method with 15 mice in each group. Mice in group A, B were respectively injected with 2 ml exogenous T₃ solutions 10, 5 μg/kg intraperitoneally. Mice in control group were injected with 2 ml normal saline. Three mice of each group were put to death respectively on day 0, 7, 14, 21, 42 after treatment. The total liver weight of the mice was measured after death. The proliferation of liver cells was detected by immunohistochemistry. The experimental data were compared using t test or analysis of variance.

Compared with control group, the liver weight of mice in group A increased significantly on day 7, 14, 21, 42 after treatment (t=3.298, 6.760, 7.119, 6.128; P<0.05) , and the liver weight of mice in group B increased significantly on day 14, 21, 42 after treatment (t=4.188, 4.570, 2.978; P<0.05). The increased liver weight in group A was significantly more than that in group B on day 7, 14, 21, 42 after treatment (t=4.935, 4.303, 4.033, 4.480; P<0.05). The liver weight in group A, B rose to the top on day 21 after treatment (F=21.480, 11.244; P<0.05). Compared with control group, the liver cell count in group A increased significantly on day 0, 7, 14, 21, 42 after treatment (t=28.383, 23.842, 40.194, 31.059, 15.841; P<0.05), and the same with group B (t=9.097, 7.680, 20.597, 42.192, 14.415; P<0.05). The increased liver cell count in group A was significantly more than that in group B (t=8.016, 4.872, 10.719, 9.514, 7.831; P<0.05). The liver cell count rose to the top in group A on day 14 after treatment (F=169.190, P<0.05) and rose to the top in group B on day 21 after treatment (F=90.460, P<0.05). Extensive proliferation of liver cells was observed both in group A and B after treatment.

Exogenous T₃ can effectively promotes the liver hyperplasia of mouse, and the hyperplasia becomes more significant as the T₃ concentration rises.