|
|
||||||||
Departments of Medicine and Physiology and Cellular Biophysics, College of Physicians and Surgeons and St. Luke's-Roosevelt Hospital Center, Columbia University, New York, New York 10019
Although alveoli clear liquid by active transport, the presence of surface-active material on the alveolar surface suggests that convective mechanisms for rapid liquid removal may exist. To determine such mechanisms, we held the isolated blood-perfused rat lung at a constant alveolar pressure (PA). Under videomicroscopy, we micropunctured a single alveolus to infuse saline or Ringer solution in ~10 adjacent alveoli. Infused alveoli were lost from view. However, as the infused liquid cleared, the alveoli reappeared and their diameters could be quantified. Hence the time-dependent determination of alveolar diameter provided a means for quantifying the time to complete liquid removal (Ct) in single alveoli. All determinations were obtained at an PA of 5 cmH2O. Ct, which related inversely to alveolar diameter, averaged 4.5 s in alveoli with the fastest liquid removal. Injections of dye-stained liquid revealed that the liquid flowed from the injected alveoli to adjacent air-filled alveoli. Lung hyperinflations instituted by cycling PA between 5 and 15 cmH2O decreased Ct by 50%. Chelation of intracellular Ca2+ prolonged Ct and abolished the inflation-induced enhancement of liquid removal. We conclude that when liquid is injected in a few alveoli, it rapidly flows to adjacent air-filled alveoli. The removal mechanisms are dependent on alveolar size, inflation, and intracellular Ca2+. We speculate that removal of liquid from the alveolar surface is determined by the curvature and surface-active properties of the air-liquid interface.
surfactant; pulmonary edema; cell calcium; Laplace equation; inflation
This article has been cited by other articles:
![]() |
E. U. Azeloglu, J. Bhattacharya, and K. D. Costa Atomic force microscope elastography reveals phenotypic differences in alveolar cell stiffness J Appl Physiol, August 1, 2008; 105(2): 652 - 661. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. E. Perlman and J. Bhattacharya Alveolar expansion imaged by optical sectioning microscopy J Appl Physiol, September 1, 2007; 103(3): 1037 - 1044. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Lindert, C. E. Perlman, K. Parthasarathi, and J. Bhattacharya Chloride-Dependent Secretion of Alveolar Wall Liquid Determined by Optical-Sectioning Microscopy Am. J. Respir. Cell Mol. Biol., June 1, 2007; 36(6): 688 - 696. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. M. Kuebler, K. Parthasarathi, J. Lindert, and J. Bhattacharya Real-time lung microscopy J Appl Physiol, March 1, 2007; 102(3): 1255 - 1264. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Bhattacharya Alveolocapillary Cross-Talk: Giles F. Filley Lecture Chest, December 1, 2005; 128(6_suppl): 553S - 555S. [Full Text] [PDF] |
||||
![]() |
R. H. Hastings, H. G. Folkesson, and M. A. Matthay Mechanisms of alveolar protein clearance in the intact lung Am J Physiol Lung Cell Mol Physiol, April 1, 2004; 286(4): L679 - L689. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Matthay, C. Clerici, and G. Saumon Lung Edema Clearance: 20 Years of Progress: Invited Review: Active fluid clearance from the distal air spaces of the lung J Appl Physiol, October 1, 2002; 93(4): 1533 - 1541. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Matthay, H. G. Folkesson, and C. Clerici Lung Epithelial Fluid Transport and the Resolution of Pulmonary Edema Physiol Rev, July 1, 2002; 82(3): 569 - 600. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. O'Brodovich Pulmonary edema fluid movement within the lung Am J Physiol Lung Cell Mol Physiol, December 1, 2001; 281(6): L1324 - L1326. [Full Text] [PDF] |
||||
![]() |
P. M. Wang, E. Fujita, and J. Bhattacharya Mechanotransduction in the Lung: Vascular regulation of type II cell exocytosis Am J Physiol Lung Cell Mol Physiol, May 1, 2002; 282(5): L912 - L916. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |