肺泡上皮细胞钠-钾ATP酶与海水淹溺型肺水肿

On Na^+-K^+-ATPase of Alveolar Epithelial Cell and Pulmonary Edema Sea-water-drowned

钠-钾ATP酶(Na^+-K^+-ATPase)对于维持胞质渗透压和细胞容积的相对稳定以及细胞内pH的稳定具有重要的生理意义。肺泡上皮具有阻止液体进入肺泡腔内和主动清除肺泡腔内液体的作用,是抵抗肺泡性肺水肿形成的一道重要屏障。这一功能的完成有赖于Ⅱ型肺泡上皮细胞对钠离子的主动转运和分布于Ⅰ型、Ⅱ型肺泡上皮细胞的特殊水通道,而钠离子的主动转运依靠钠-钾ATP酶来完成。海水淹溺型肺水肿(PE-SWD)是以低氧血症及代谢性酸中毒为主要病理生理学特点的临床病症。PE-SWD发生时,Na^+-K^+-ATPase活性的改变直接影响到细胞膜外Na^+、K^+、等离子的浓度和分布,既是造成PE-SWD发生的多种因素所引起的直接恶果,又是促进PE-SWD不断发生的继发性原因。因此认识肺泡上皮细胞钠-钾ATP酶在PE-SWD发病中的作用对于PE-SWD的治疗具有重要意义。本文就钠-钾ATP酶的功能、结构、调节机制及钠-钾ATP酶在PE-SWD发病中的作用作一综述。

The sodium-potassium ATP enzyme （Na^＋-K^＋-ATPase） is of the important physiological significance in maintaining the cytoplasm osmotic pressure and the cell volume relative stability as well as the stability of the intra-cellular pH. The alveolar epithelium cell is able to prevent liquid from entering the pulmonary alveolar space, and initiatively eliminate the liquid of pulmonary alveolar space, which is an important barrier to resist the formation of vesicular pulmonary edema. This function depends on actively transporting the sodium ion of type II alveolar epithelial cells and the special water passages distributed in Ⅰ /Ⅱ alveolar epithelial cells. While the active transportation of sodium ion depends on Na^＋-K^＋-ATPase. Hyoxemia and metabolic acidosis act as the major pathophysiologic features of pulmonary edema sea-water-drowned （PE-SWD）. When PE-SWD occurs, the change of Na^＋-K^＋-ATPase activity directly affects the density and the distribution of Na^＋, K^＋ in the membrane and out of membrane of cells. It is not only a directive consequence by many factors which create PE-SWD, but also a sequential reason which promotes PE-SWD. Therefore recognization of the effection of Na^＋-K^＋-ATPase in alveolar epithelial cell on PE-SWD is of important significance for the treatment of PE-SWD. The role of Na^＋-K^＋-AT- Pase and the relation with PE-SWD were reviewed in this paper.