Mechanisms of surface tension reduction by pulmonary surfactant

肺表面活性物质是肺中的一种物质，它使人们能够以最小的努力呼吸。这在早产儿中很明显，由于缺乏表面活性剂，他们呼吸困难。我们的实验室旨在了解表面活性剂的工作原理。虽然以前的研究已经阐明了表面活性剂功能的许多一般方面，但一些技术限制使我们无法研究特定组分对表面活性剂功能的影响。 在目前的应用中，我们使用一种新的工具，所谓的约束座滴表面活性计，以评估表面活性剂如何工作，以及如何特定的组件有助于其功能。为了评估后一个问题，我们将比较具有不同呼吸生理学的不同物种的表面活性剂。例如，我们将比较小鼠和大鼠等高呼吸率动物的表面活性剂与猪和牛等低呼吸率动物的表面活性剂，我们将比较冬眠期间在5OC呼吸的动物的表面活性剂与在37 oC呼吸的动物的表面活性剂。然后，我们将改变这些动物的表面活性剂的组成，以观察我们是否可以确定负责动物特异性效应的表面活性剂的组分。例如，我们将小鼠表面活性剂的成分之一改变为在奶牛表面活性剂中观察到的水平，并观察表面活性剂的行为是否相应改变。我们将重点关注的表面活性剂的一个特定组分是胆固醇，因为尚不清楚该化合物（存在于从不同物种分析的所有表面活性剂中）如何有助于表面活性剂的功能。这项研究将作为两名新研究生研究培训计划的一部分进行，将提供有关肺表面活性物质功能的新科学信息，并帮助我们了解具有不同呼吸特征的不同物种的肺如何工作。

Pulmonary surfactant is a material in the lung that allows people to breathe with minimal effort. This is evident in babies born prematurely which due to the lack of surfactant have trouble breathing. Our laboratory aims to understand how surfactant works. Although previous research has elucidated many general aspects of surfactant function, some technical limitations have prevented us from studying the details by which specific components contribute to surfactant function. In the current application we use a novel tool, the so-called constrained sessile drop surfactometer, to assess how surfactant works and how specific components contribute to its function. To assess the latter question, we will compare surfactants from different species that have different respiratory physiology. For example, we will compare surfactant from animals with a high breathing rate like mice and rats with surfactant from animals with a slow breathing rate like pigs and cows, and we will compare surfactant from animals that breathe at 5OC during hibernation to surfactant from animals that were breathing at 37oC animals. We will then make changes to the composition of the surfactant from those animals to observe if we can determine the components of the surfactant that are responsible for the animal-specific effects. For example, we will change the one of the ingredients of the surfactant from mice to the level observed in surfactant from cows and observe if the behavior of the surfactant changes accordingly. One specific component of surfactant that we will focus on is cholesterol, as it is still unclear how this compound, which is present in all surfactants analyzed from different species, contribute to the function of surfactant. This research, which will be performed as part of the research training program for two new graduate students, will provide new scientific information on the function of pulmonary surfactant and help us understand how the lung works in different species with different breathing characteristics.