Postnatal lung growth: evidence that the gas-exchange region grows fastest at the periphery.
Postnatal lung growth: evidence that the gas-exchange region grows fastest at the periphery.
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产后肺部生长：证据表明气体交换区域在外围生长最快。
DOI：
10.1152/ajplung.1993.265.4.l319
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Massaro,D
中科院分区：
文献类型：
--
作者：
Massaro,GD;Massaro,D
未成熟肺泡形成肺泡后气体交换区域扩大的位置(S)尚不清楚，但这一信息可能对研究肺生长的调节很重要。尽管我们知道它所依赖的重要假设，但我们进行了这项研究，以测试肺的气体交换区域在胸膜下直接区域比在中央更快地扩大的想法。为了标记气体交换区域的间质，从23天到135天(112天)给大鼠提供含银的水。其中一些在135天龄时被杀死，另一些在白银暴露结束后51天(186天)被杀死。我们认为在间质中形成的银粒是肺存在或在银暴露期间形成的标志，暴露后增加的组织会减少颗粒数密度，生长最快的部位的颗粒密度最低。在暴露于银的第112天被杀的大鼠，其直接胸膜下气体交换基质中的银粒密度比更中心的气体交换基质中的银粒密度低28%。白银暴露结束51天后处死的大鼠，胸膜下直接区域的颗粒密度比气体交换区域的中央基质低65%。暴露结束51天后处死的大鼠，中央基质中的颗粒密度比暴露第112天时处死的大鼠相应区域的颗粒密度低33%，外围基质中的颗粒密度低67%。
The site(s) at which the gas-exchange region enlarges after alveoli are formed from the saccules of the immature lung is unclear; however, this information might be important to studies of the regulation of lung growth. Although aware of important assumptions on which it rests, we undertook this study to test the idea that the lung's gas-exchange region enlarges more rapidly in the immediate subpleural region than more centrally. To label the interstitium of the gas-exchange region, rats were provided silver-containing water from age 23 to 135 days (112 days). Some were killed at age 135 days, others 51 days after silver exposure ended (age 186 days). We considered silver grains that formed in the interstitium as a marker of lung present or formed during silver exposure; tissue added after exposure would diminish the numerical density of grains and the fastest growing sites would have the lowest grain density. Rats killed on the 112th day of silver exposure had a silver grain density in their immediate subpleural gas-exchange matrix that was 28% lower than in their more central gas-exchange matrix. Rats killed 51 days after silver exposure ended had a grain density in the immediate subpleural region that was 65% lower than in the central matrix of the gas-exchange region. The grain density in the rats killed 51 days after silver exposure ended was 33% lower in the central matrix and 67% lower in the peripheral matrix than in the respective regions of rats killed on day 112 of exposure.(ABSTRACT TRUNCATED AT 250 WORDS)