Lung collagen composition and synthesis. Characterization and changes with age.
Lung collagen composition and synthesis. Characterization and changes with age.
复制标题
肺胶原蛋白的组成和合成。
DOI：
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发表时间：
1974
影响因子：
4.8
通讯作者：
R. Crystal
中科院分区：
文献类型：
--
作者：
K. Bradley;S. D. Mcconnell;R. Crystal
在肺中，胶原蛋白与支气管、血管和肺泡间质有关；众所周知，它是维持肺结构和功能的基础。从兔肺匀浆中可提取α1和α2两条胶原链；每条链的分子量约为100,000，由胶原蛋白特有的氨基酸组成，但不是肺所特有的。体外培养的肺切片合成α1和α2链，经羧甲基纤维素层析、十二烷基硫酸钠丙烯酰胺凝胶电泳、酸性丙烯酰胺凝胶电泳、胶原酶敏感性和90°三氯乙酸敏感性检测证实。肺蛋白占干重的百分比在成熟过程中变化不显著，但胶原蛋白含量从妊娠后期到成年增加5倍。从胎儿到成年，每个细胞的胶原蛋白合成的平均速率缓慢下降10倍，而每个细胞的非胶原蛋白合成的平均速率在出生前迅速下降到成年水平。胶原蛋白合成率相对于总蛋白合成率在胎儿时期较低，在出生后的第一个月从2%上升到15%，然后在成年后的2个月龄下降到胎儿水平。因此，成熟的肺在快速生长期间，随着肺转变为气体交换器官，基因表达会发生显著变化。
Abstract In the lung, collagen is found associated with bronchi, with blood vessels, and with the alveolar interstitium; it is known to be fundamental in the maintenance of lung structure and function. Two collagen chains, α1 and α2, can be extracted from rabbit lung homogenates; each chain has an approximate molecular weight of 100,000 and is composed of amino acids that are characteristic of collagen, but are not specific for lung. Lung slices incubated in vitro synthesize α1 and α2 chains, as demonstrated by carboxymethylcellulose chromatography, by sodium dodecyl sulfate acrylamide gel electrophoresis, by acidic acrylamide gel electrophoresis, by sensitivity to collagenase, and by sensitivity to trichloroacetic acid at 90°. As a percentage of dry weight, lung protein does not change significantly during maturation, but the content of collagen increases 5-fold from the late stages of gestation to adult life. The average rate of collagen synthesis per cell decreases slowly 10-fold from fetal to adult life whereas the average rate of noncollagen protein synthesis per cell rapidly decreases to adult levels before birth. The rate of collagen synthesis relative to the rate of total protein synthesis is low in fetal life, rises from 2 to 15% in the first month of life, and then declines by 2 months of age to the fetal level throughout adult life. The maturing lung, therefore, has significant changes in genetic expression during a period of rapid growth as the lung converts to a gas-exchanging organ.