Davies P, Maddalo F, Reid L
Exp Lung Res. 1984;7(2):93-100. doi: 10.3109/01902148409069670.
Because of the difficulty in isolating precapillary or postcapillary segments of the pulmonary microcirculation, there is little information on their reactivity even though they are important in normal lung function and play a crucial role in the pathogenesis of pulmonary hypertension. In order to study the reactivity of microvessels in lung we have developed a method in which thin slices of tissue are incubated in vitro with a vasoactive drug and are then fixed, embedded, and sectioned at a thickness of 1 micron. Vessel profiles are analyzed on a computer graphics tablet, and their degree of constriction is determined morphometrically. In this system, muscular arteries less than 200 microns in diameter in adult rat lung explants are moderately constricted, but they constrict further when incubated with 1-norepinephrine (10(-4), 10(-5) M), an effect maintained for 30 min. Nonmuscular vessels (arteries and veins) less than 100 microns in diameter also constrict in response to similar doses of norepinephrine. Although the effector cells remain to be identified, it is likely that pericytes and precursor muscle cells in the walls of these vessels are at least partly responsible.
由于分离肺微循环的毛细血管前或毛细血管后节段存在困难，尽管它们在正常肺功能中很重要且在肺动脉高压的发病机制中起关键作用，但关于它们反应性的信息却很少。为了研究肺微血管的反应性，我们开发了一种方法，即把薄组织切片在体外与血管活性药物一起孵育，然后固定、包埋，并切成1微米厚的切片。在计算机图形输入板上分析血管轮廓，并通过形态计量学确定其收缩程度。在这个系统中，成年大鼠肺外植体中直径小于200微米的肌性动脉会适度收缩，但与1-去甲肾上腺素（10⁻⁴、10⁻⁵M）一起孵育时会进一步收缩，这种效应持续30分钟。直径小于100微米的非肌性血管（动脉和静脉）对类似剂量的去甲肾上腺素也有收缩反应。尽管效应细胞有待确定，但这些血管壁中的周细胞和前体细胞很可能至少部分起作用。
