Triiodothyronine stimulates maturation of porcine growth-plate cartilage in vitro.
Triiodothyronine stimulates maturation of porcine growth-plate cartilage in vitro.
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三碘甲腺原氨酸在体外刺激猪生长板软骨的成熟。
DOI：
10.1172/jci110641
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Lebovitz,HE
中科院分区：
文献类型：
--
作者：
Burch,WM;Lebovitz,HE
我们研究了三碘甲腺原氨酸(T3)对体外培养的哺乳动物生长板软骨的影响。取胎猪肩胛骨生长板软骨，在无血清培养液和含T3的培养液中培养3~7d。培养3d后，T3(10 NM)处理的生长板软骨的碱性磷酸酶活性比单独培养的软骨高152+/-36%，7d后增加324+/-47%，是软骨细胞肥大的标志。在0.01-10 nM范围内，T_3对碱性磷酸酶的活性有剂量效应增加。碱性磷酸酶活性的升高是T3特有的，因为皮质醇、胰岛素、甲状旁腺激素或5%胎牛血清不能提高生长板软骨碱性磷酸酶的活性。生长板软骨的组织学研究表明，T3以浓度依赖的方式增加成熟区(肥大的软骨细胞)的宽度。碱性磷酸酶组织化学染色显示，T3使新细胞重新聚集到成熟区。T3还能刺激生长板软骨中L-[~3H]亮氨酸掺入蛋白质，~(35)SO_4掺入蛋白多糖。相反，T3没有增加碱性磷酸酶的活性，也没有增加放射性标记的前体掺入非生长板肩关节软骨中。这些研究表明，T3直接刺激胎儿哺乳动物生长板软骨的成熟，并在较小程度上刺激与生长相关的过程。
We studied the effect of triiodothyronine (T3) on mammalian growth-plate cartilage in vitro. Growth-plate cartilages from fetal pigs scapulae were incubated for 3 to 7 d in serum-free medium alone or medium containing T3. Alkaline phosphatase activity, a marker of hypertrophied chondrocytes, was increased in T3 (10 nM)-treated growth-plate cartilage 152 +/- 36% above that of cartilage incubated in medium alone after 3 d of incubation, and 324 +/- 47% after 7 d of incubation. There was a dose-response increase in alkaline phosphatase activity to T3 over the range of 0.01-10 nM. The rise in alkaline phosphatase activity was specific for T3 since growth-plate cartilage alkaline phosphatase activity was not increased by cortisol, insulin, parathyroid hormone, or 5% fetal calf serum. Histological studies of growth-plate cartilage showed that T3 in a concentration-dependent manner increased the width of the zone of maturation (hypertrophied chondrocytes). Histochemical staining for alkaline phosphatase activity demonstrated that T3 caused the recruitment of new cells into the zone of maturation. T3 also stimulated incorporation of L-[3H]leucine into protein and 35SO4 into proteoglycan in growth-plate cartilage. In contrast, T3 did not increase alkaline phosphatase activity or radiolabeled precursor incorporation into nongrowth-plate scapular cartilage. These studies demonstrate that T3 directly stimulates maturation and, to a lesser degree, growth-related processes in fetal mammalian growth-plate cartilage.Images