Comparison of elastic properties and contractile responses of isolated airway segments from mature and immature rabbits
Comparison of elastic properties and contractile responses of isolated airway segments from mature and immature rabbits
复制标题
DOI：
10.1152/japplphysiol.00362.2002
复制
发表时间：
2003-07-01
影响因子：
3.3
通讯作者：
Tepper, RS
中科院分区：
文献类型：
--
作者：
Ramchandani, R;Shen, X;Tepper, RS
与成熟动物相比，未成熟兔体内支气管收缩的最大气道变窄程度更大。由于孤立的未成熟肺具有较低的剪切模量，因此尚不清楚未成熟肺中更大的气道变窄是否继发于气道和肺实质之间的束缚较少或成熟和未成熟气道的机械特性的差异。在本研究中，我们比较了成熟和未成熟兔子同一代的充满液体的、孤立的实质内气道段的机械特性。与成熟支气管相比，乙酰胆碱刺激导致未成熟支气管的气道变窄程度更大。与成熟的支气管相比，未成熟的支气管更顺应，具有较低的静息气道容量，并且更容易塌陷。当气道在等容条件下与ACh收缩时，未成熟的支气管产生更大的主动压力，并且比成熟的支气管对ACh更敏感。我们的结果表明，在没有肺实质的情况下气道结构和功能的成熟差异可以解释体内未成熟气道比成熟气道更大的最大狭窄。
Immature rabbits have greater maximal airway narrowing with bronchoconstriction in vivo compared with mature animals. As isolated immature lungs have a lower shear modulus, it is unclear whether the greater airway narrowing in the immature lung is secondary to less tethering between the airways and the lung parenchyma or to differences in the mechanical properties of the mature and immature airways. In the present study, we compared the mechanical properties of fluid-filled, isolated, intraparenchymal airway segments of the same generation from mature and immature rabbits. Stimulation with ACh resulted in greater airway narrowing in immature than mature bronchi. The immature bronchi were more compliant, had a lower resting airway volume, and were more collapsible compared with the mature bronchi. When the airways were contracted with ACh under isovolume conditions, the immature bronchi generated greater active pressure, and they were more sensitive to ACh than were mature bronchi. Our results suggest that maturational differences in the structure and function of the airways in the absence of the lung parenchyma can account for the greater maximal narrowing of immature than mature airways in vivo.