Shumko J Z, Feinberg R N, Shalvoy R M, DeFouw D O
Department of Anatomy, Cell Biology, and Injury Sciences, UMDNJ--New Jersey Medical School, Newark 07103.
Exp Lung Res. 1993 May-Jun;19(3):283-97. doi: 10.3109/01902149309064347.
Direct measurements of pleural fluid hydrostatic and colloid osmotic pressures after infusion of saline, bovine serum albumin, or silicone into the pleural space were coupled with ultrastructural morphometric analyses to assess the response of pleural mesothelial cells to hydrothorax. Increases of hydrostatic pressure, either independent or in combination with decreases of osmotic pressure, served to increase the number of plasmalemmal vesicles in mesothelial cells of both the visceral and parietal pleurae. These results support the hypothesis that an increase in vesicle numerical density represents a response to elevations of extracellular fluid pressures. Fluid resorption from the pleural space with subsequent accumulation within the visceral pleural interstitium was also associated with the formation of invaginations of the mesothelial basal plasmalemma. That the invaginations were not observed in the absence of interstitial fluid accumulation supports the concept that basal surface invaginations represent distortions of mesothelial cell membranes in response to pressure differentials across the plasmalemma. The results of this study are most consistent with the interpretation that increased numbers of plasmalemmal vesicles and invaginations of the basal plasmalemma represent adaptive conformational mechanisms of pleural mesothelial cells to prevent monolayer disruption by elevated extracellular fluid pressures.
向胸腔内注入生理盐水、牛血清白蛋白或硅酮后，直接测量胸腔积液的静水压力和胶体渗透压，并结合超微结构形态计量分析，以评估胸膜间皮细胞对胸腔积液的反应。无论是单独增加静水压力，还是与渗透压降低相结合，都能增加脏层和壁层胸膜间皮细胞中质膜囊泡的数量。这些结果支持了这样一种假说，即囊泡数量密度的增加代表了对细胞外液压力升高的一种反应。胸腔内液体的再吸收以及随后在内脏胸膜间质内的积聚也与间皮细胞基底质膜内陷的形成有关。在没有间质液积聚的情况下未观察到内陷，这支持了基底表面内陷代表间皮细胞膜因质膜两侧压力差而发生扭曲的观点。本研究结果最符合这样一种解释，即质膜囊泡数量的增加和基底质膜的内陷代表了胸膜间皮细胞的适应性构象机制，以防止细胞单层因细胞外液压力升高而破坏。
