Autoradiographic localization of specific [3H]dexamethasone binding in fetal lung.
Autoradiographic localization of specific [3H]dexamethasone binding in fetal lung.
复制标题
胎儿肺中特异性[3H]地塞米松结合的放射自显影定位。
DOI：
10.1016/0012-1606(84)90292-6
复制
发表时间：
1984
影响因子：
2.7
通讯作者：
Malkinson,AM
中科院分区：
文献类型：
--
作者：
Beer,DG;Butley,MS;Cunha,GR;Malkinson,AM
在不同发育阶段的胎鼠肺和妊娠8周的人胎肺中，采用快速体外类固醇孵育技术和融片放射自显影技术检测特异性[3H]地塞米松结合的细胞和亚细胞定位。与未标记类固醇的竞争研究证实了[3H]地塞米松标记的特异性，并表明胎儿肺间质是肺发育过程中糖皮质激素的主要靶点。定量结合研究，包括完整组织与竞争配体的孵育和随后的亚细胞分离，表明这是糖皮质激素受体特异性的核结合特征。早期发育阶段肺组织[3H]地塞米松结合的x线自显像显示，直接靠近细支气管网络近端部分的间质被大量标记。相比之下，随后分化为支气管和细支气管的上皮相对未标记。生长上皮的远端部分，注定成为肺泡管和肺泡，确实显示[3H]地塞米松的核定位。由于已知间质在控制肺发育中的重要性以及糖皮质激素刺激肺发育的能力，这些结果表明糖皮质激素的许多促进生长的作用可能是通过间质介导的。此外，通过利用一种允许同时检测细胞外基质成分和[3H]地塞米松结合的技术，观察到广泛的间质[3H]地塞米松结合与广泛的细胞外基质积累之间的关系。由于糖皮质激素刺激许多细胞外基质成分的合成，这些结果表明这些激素在肺形态发生过程中影响间充质-上皮相互作用。
The cellular and subcellular localization of specific [3H]dexamethasone binding was examined in fetal mouse lung at various stages of development and in human fetal lung at 8 weeks of gestation using a rapidin vitrosteroid incubation technique followed by thaw-mount autoradiography. Competition studies with unlabeled steroids demonstrate the specificity of [3H]dexamethasone labeling, and indicate that fetal lung mesenchyme is a primary glucocorticoid target during lung development. Quantitative binding studies, involving incubation of intact tissue with competing ligand and subsequent subcellular fractionation, show this to be specific, nuclear binding characteristic of glucocorticoid receptors. Autoradiographs of [3H]dexamethasone binding in lung tissue at early stages of development demonstrate that the mesenchyme directly adjacent to the more proximal portions of the bronchiolar network is heavily labeled. In contrast, the epithelium which will later differentiate into bronchi and bronchioles, is relatively unlabeled. Distal portions of the growing epithelium, destined to become alveolar ducts and alveoli, do show nuclear localization of [3H]dexamethasone. Because of the known importance of the mesenchyme in controlling lung development and the ability of glucocorticoids to stimulate lung development, these results suggest that many of the growth-promoting effects of glucocorticoids may be mediated through the mesenchyme. In addition, by utilizing a technique which allows the simultaneous examination of extracellular matrix components and [3H]dexamethasone binding, a relationship is observed between extensive mesenchymal [3H]dexamethasone binding and extensive extracellular matrix accumulation. Since glucocorticoids stimulate the synthesis of many extracellular matrix components, these results suggest a role for these hormones in affecting mesenchymal-epithelial interactions during lung morphogenesis.