甲状腺素及肾上腺素致兔粒细胞分布变化

Changes of granulocyte distribution induced by thyroxin and epinephrine： experiment with rabbits

目的观察兔甲状腺毒症时血粒细胞分布的变化，了解甲状腺毒症时粒细胞减少与边缘池粒细胞聚集是否有关。方法45只健康家兔分为肾上腺素组、标记组及对照组，每组15只。肾上腺素组及标记组饲喂左甲状腺素钠（L-T4）300μg·kg^-·d^-1，共14d，用L-T4前后测心电图、静脉血游离T3（FT3）、游离T4（T4）、白细胞及粒细胞数，肾上腺素组第14天皮下注射。肾上腺素0．07mg／kg，20min后再次纪录粒细胞数变化。标记组及对照组第14天静脉注射^131I标记抗粒细胞单克隆抗体后6h分别测定心、肝、脾、肌肉组织放射性计数（CPM）与血CFM比值。结果肾上腺素组及标记组14d后心率明显加快；FT3、FT4上升[用L-T4前FT3（5．58±1．05）pmol／L、FT4（9．20±1．50）pmol／L，用L-T4 14d后FT3（9．79±1．94）pmol／L、FT4（11．29±2．09）pmol／L]；静脉血白细胞及粒细胞计数显著减少用L-T4前白细胞（10．75±1．91）×10^9／L、粒细胞数（5．26±1．19）×10^9／L，用L-T4 14d后白细胞（7．37±2．90）×10^9／L、粒细胞数（2．91±1．48）×10^9／L，肾上腺素组注射肾上腺素后粒细胞动员进入了循环血流，13／15兔粒细胞数上升；其中7只上升到注射肾上腺素前的2—4．8倍。标记组心、肝、脾、肌肉各组织与血CPM／g比值分别明显高于对照组。结论家兔实验性甲状腺毒症时循环粒细胞减少、分布异常，存在边缘池粒细胞聚集现象。

Objective To investigate the distribution of granulocyte during thyrotoxicosis and the relation of granulopenia and the gathering of circulating granulocytes into the marginal pool. Methods Fortyfive rabbits were randomly divided into 3 equal groups ： epinephrine group fed with levo-tyroxin （LT4） for 14 days, injected subcutaneously with epinephrine 0.07 mg/kg, and undergoing collection of peripheral blood samples for white blood cell and granulocyte counts, free blood triiodothyroxine （FT3） and free blood thyroxine （FT4）, electrocardiography, and body weight measurement; labeled group fed with LT4 for 14 days, injected subcutaneously with ^131 I-labeled anti-human grannlocyte monoclonal antibody, and killed 6 hours later to calculate the ratio of radioactivity of heart, liver, spleen, and muscle tissues to blood （ CPM/ g）, and control group, not fed with L-T4 but injected with ^131I-labeled anti-human granulocyte monoclonal antibody on the day 14, and killed 6 hours later to calculate the ratio of radioactivity of tissues to blood. Results After 14-day feeding of L-T4, the heart rates of the epinephrine and labeled groups were significantly higher than those before injection, and the FT3 and FT4 levels were significantly increased;the venous WBC and granulocyte counts were significantly reduced. But the granulocyte count of 13 of the 15 rabbits in the epinephrine group increased 20 minutes after the injection of epinephrine, even becoming 2 - 4.8 times as high as those before the injection in 7 rabbits. The heart, liver, spleen, and muscle tissues to blood CPM/g ratios of the labeled group were all significantly higher than those of the control group （ all P 〈 0.01 ）. Conclusion During thyrotoxicosis the circulating granulocytes are reduced and the distribution of circulating granulocytes is abnormal with a gathering phenomenon of the granulocytes into the marginal pool.