Departamento de Clínica Médica, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil.
Clinics (Sao Paulo). 2011;66(10):1797-803. doi: 10.1590/s1807-59322011001000020.
To verify the accordance of functional and morphometric parameters during the development of emphysema.
BALB/c mice received a nasal drop of either papain or saline solution and were studied after 1, 3, 15, 28, and 40 days. Functional parameters, such as airway resistance, tissue damping, and tissue elastance, were analyzed. To evaluate the structural changes and possible mechanisms involved in this disease, we measured the mean linear intercept, the volume proportions of elastic and collagen fibers, the number of macrophages, the numbers of cells expressing metalloprotease 12 and 8-isoprostane in lung parenchyma.
We only observed decreases in tissue elastance and tissue damping on the 28th day, with a concomitant increase in the mean linear intercept, indicating the presence of emphysema. However, only the mean linear intercept values remained increased until the 40th day. The volume proportion of collagen fibers was increased from the 15th day to the 40th day, whereas the volume proportion of elastic fibers was only increased on the 40th day. The number of macrophages increased beginning on the 1st day. The expression of metalloproteinase 12 was increased from the 3rd day until the 40th day. However, 8-isoprostane expression was only increased on the 1st and 3rd days.
In this study, morphometric parameters were found to be more reliable for detecting the presence of emphysema than the functional parameters measured by respiratory mechanics. Further investigations are necessary to understand how the extracellular matrix remodeling observed in the lung parenchyma could be involved in this process.
验证肺气肿发展过程中功能和形态计量学参数的一致性。
BALB/c 小鼠鼻腔滴注木瓜蛋白酶或生理盐水，分别于 1、3、15、28 和 40 天后进行研究。分析气道阻力、组织阻尼和组织弹性等功能参数。为了评估结构变化和涉及该疾病的可能机制，我们测量了平均线性截距、弹性纤维和胶原纤维的体积比例、肺实质中巨噬细胞的数量、表达金属蛋白酶 12 和 8-异前列腺素的细胞数量。
仅在第 28 天观察到组织弹性和组织阻尼降低，同时平均线性截距增加，表明存在肺气肿。然而，只有平均线性截距值一直增加到第 40 天。胶原纤维体积比例从第 15 天增加到第 40 天，而弹性纤维体积比例仅在第 40 天增加。巨噬细胞数量从第 1 天开始增加。金属蛋白酶 12 的表达从第 3 天增加到第 40 天。然而，8-异前列腺素的表达仅在第 1 天和第 3 天增加。
在这项研究中，形态计量学参数比呼吸力学测量的功能参数更可靠地检测到肺气肿的存在。需要进一步研究以了解观察到的肺实质细胞外基质重塑如何参与这一过程。
