Breath-by-breath measurement of particle deposition in the lung of spontaneously breathing rats.
Breath-by-breath measurement of particle deposition in the lung of spontaneously breathing rats.
复制标题
自主呼吸大鼠肺部颗粒沉积的逐次呼吸测量。
DOI：
10.1152/japplphysiol.00096.2009
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Schulz,H
中科院分区：
文献类型：
--
作者：
Karrasch,S;Eder,G;Bolle,I;Tsuda,A;Schulz,H
已经描述了许多人类和实验动物的沉积模型。然而，到目前为止，还没有关于大鼠呼吸沉积测量的报道。本研究的目的是确定微米大小颗粒的肺沉积作为一个功能的呼吸参数在成年大鼠肺。设计了一种新的气溶胶光度测定系统，用于测量麻醉、插管和自然呼吸的90日龄Wistar-Kyoto大鼠体内非吸湿性2 μm脂脂酸颗粒的沉积。系统的仪器死区最小至310 μl（即呼吸死区约20%）。该系统可以连续监测呼吸量中的颗粒浓度。在不同麻醉水平下监测呼吸参数，如呼吸频率(f)、潮气量（Vt）以及吸气/呼气时间。结果表明，正常呼吸时vtv在1.5 ~ 4.0 ml之间变化，单次呼吸时vtv在4.0 ~ 10.0 ml之间变化；F范围从40到200次呼吸/分钟。相应的沉积值在5%到50%之间变化，这取决于每次呼吸的呼吸方式。通过v和f的双线性函数，得到了与沉积(D)的最佳拟合，D = 11.0 ~ 0.09·f + 3.75·Vt。我们的结论是，我们的方法为测量沉积提供了比使用通风动物的传统模型更现实的条件，并允许我们分析呼吸特异性沉积与自发呼吸模式之间的相关性。
A number of deposition models for humans, as well as experimental animals, have been described. However, no breath-by-breath deposition measurement in rats has been reported to date. The objective of this study is to determine lung deposition of micrometer-sized particles as a function of breathing parameters in the adult rat lung. A new aerosol photometry system was designed to measure deposition of nonhygroscopic, 2-μm sebacate particles in anesthetized, intubated, and spontaneously breathing 90-day-old Wistar-Kyoto rats placed in a size-adjusted body plethysmograph box. Instrumental dead space of the system was minimized down to 310 μl (i.e., ∼20% of respiratory dead space). The system allows continuous monitoring of particle concentration in the respired volume. Breathing parameters, such as respiratory rate (f), tidal volume (Vt), as well as inspiration/expiration times, were also monitored at different levels of anesthesia. The results showed that Vttypically varied between 1.5 and 4.0 ml for regular breathing and between 4.0 and 10.0 ml for single-sigh breaths; f ranged from 40 to 200 breaths/min. Corresponding deposition values varied between 5 and 50%, depending on breath-by-breath breathing patterns. The best fit of deposition (D) was achieved by a bilinear function of Vtand f and found to be D = 11.0 − 0.09·f + 3.75·Vt. We conclude that our approach provides more realistic conditions for the measurement of deposition than conventional models using ventilated animals and allows us to analyze the correlation between breath-specific deposition and spontaneous breathing patterns.