Epidermal growth factor increases lung liquid clearance in rat lungs

• Published in: Journal of applied physiology (1985) Vol. 85; no. 3; pp. 1004 - 1010
• Main Authors: Sznajder, Jacob I, Ridge, Karen M, Yeates, Donovan B, Ilekis, John, Olivera, Walter
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.09.1998; American Physiological Society
• Subjects: Air breathing; Anatomy & physiology; Animals; Biological and medical sciences; Epidermal Growth Factor - pharmacology; Fundamental and applied biological sciences. Psychology; In Vitro Techniques; Lung - drug effects; Lung - physiology; Lungs; Male; Mannitol - metabolism; Membranes - enzymology; Models, Biological; Perfusion; Plethysmography; Proteins; Rats; Rats, Sprague-Dawley; Respiratory system: anatomy, metabolism, gas exchange, ventilatory mechanics, respiratory hemodynamics; Rodents; Sodium - metabolism; Sodium-Potassium-Exchanging ATPase - metabolism; Up-Regulation - physiology; Vertebrates: respiratory system; Alveolar type II cell; Rat; Enzyme; Lung; Rodentia; Ion transport; Clearance; K; Respiratory system; Vertebrata; Mammalia; Epidermal growth factor; Na; Sodium; Hydrolases; exchanging ATPase
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.1998.85.3.1004

1  Department of Medicine, Michael Reese Hospital, and 2  University of Illinois at Chicago, Chicago, Illinois 60616 Epidermal growth factor (EGF) has been reported to stimulate the proliferation of epithelial cells and increase Na + flux and Na + -K + -ATPase function in alveolar epithelial cell monolayers. Increases in Na + -K + -ATPase in alveolar type II cells (AT2) have been associated with increased active Na + transport and lung edema clearance across the rat alveolar epithelium in a model of proliferative lung injury. Thus we tested whether administration of aerosolized EGF to rat lungs would increase active Na + transport and lung liquid clearance. Sixteen adult Sprague-Dawley male rats were randomized to three groups. To a group of six rats, an aerosol generated from 20 µg of EGF in saline was delivered to the lungs, to a second group of five rats only aerosolized saline was delivered, and a third group of five rats without treatment served as the control. Forty-eight hours postaerosolization of rat lungs with EGF there was an ~40% increase in active Na + transport and lung liquid clearance compared with control rats, in the absence of changes in 22 Na + , [ 3 H]mannitol, and albumin permeabilities. The Na + -K + -ATPase activity in AT2 cells harvested from these lungs was increased in rats that received aerosolized EGF compared with AT2 cells from both control rats and rats receiving aerosolized saline. These results support the hypothesis that in vivo delivery of EGF aerosols upregulates alveolar epithelial Na + -K + -ATPase and increases lung liquid clearance in rats. sodium-potassium-3',5'-adenosinetriphosphatase; alveolar type II cells; aerosolized drug delivery; sodium transport