title: Effects of cardiogenic edema fluid on ion and fluid transport in the adult lung.
abstract: We have previously shown that cardiogenic pulmonary edema fluid (EF) increases Na(+) and fluid transport by fetal distal lung epithelia (FDLE) (Rafii B, Gillie DJ, Sulowski C, Hannam V, Cheung T, Otulakowski G, Barker PM and O'Brodovich H. J Physiol 544: 537-548, 2002). We now report the effect of EF on Na(+) and fluid transport by the adult lung. We first studied primary cultures of adult type II (ATII) epithelium and found that overnight exposure to EF increased Na(+) transport, and this effect was mainly due to factors other than catecholamines. Plasma did not stimulate Na(+) transport in ATII. Purification of EF demonstrated that at least some agent(s) responsible for the amiloride-insensitive component resided within the globulin fraction. ATII exposed to globulins demonstrated a conversion of amiloride-sensitive short-circuit current (I(sc)) to amiloride-insensitive I(sc) with no increase in total I(sc). Patch-clamp studies showed that ATII exposed to EF for 18 h had increased the number of highly selective Na(+) channels in their apical membrane. In situ acute exposure to EF increased the open probability of Na(+)-permeant ion channels in ATII within rat lung slices. EF did increase, by amiloride-sensitive pathways, the alveolar fluid clearance from the lungs of adult rats. We conclude that cardiogenic EF increases Na(+) transport by adult lung epithelia in primary cell culture, in situ and in vivo.
authors.affiliation: Canadian Institutes of Health Research Group in Lung Development, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Shephali G
authors.initials: SG
authors.lastname: Gandhi
authors.forename: Bijan
authors.initials: B
authors.lastname: Rafii
authors.forename: Michael S
authors.initials: MS
authors.lastname: Harris
authors.forename: Alexandra
authors.initials: A
authors.lastname: Garces
authors.forename: Don
authors.initials: D
authors.lastname: Mahuran
authors.forename: Xi-Juan
authors.initials: XJ
authors.lastname: Chen
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Bao
authors.forename: Lucky
authors.initials: L
authors.lastname: Jain
authors.forename: Douglas C
authors.initials: DC
authors.lastname: Eaton
authors.forename: Gail
authors.initials: G
authors.lastname: Otulakowski
authors.forename: Hugh
authors.initials: H
authors.lastname: O'Brodovich
mesh_terms: D000818:Animals; D001692:Biological Transport; D001798:Blood Proteins / Q000378:metabolism; D002395:Catecholamines / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D016764:Cell Polarity; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D053503:Epithelial Sodium Channels / Q000378:metabolism; D015633:Extravascular Lung Water / Q000378:metabolism*; D015640:Ion Channel Gating; D007473:Ion Channels / Q000378:metabolism; D008168:Lung / Q000378:metabolism*; D008297:Male; D011650:Pulmonary Alveoli / Q000378:metabolism; D011654:Pulmonary Edema / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012964:Sodium / Q000378:metabolism
chemical_list: D001798:Blood Proteins; D002395:Catecholamines; D053503:Epithelial Sodium Channels; D007473:Ion Channels; D012964:Sodium