CC BY
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Abstracts
BOTH NA+/K+-PUMP AND NA+,K+, 2CL- COTRANSPORT CONTRIBUTE TO CELL VOLUME CONTROL IN HUMAN LUNG FIBROBLASTS
Koltsova, S.V.1' 2, Akimova, O.A.2, Orlov, S.N. 1' 2, and Dulin, N.O.3
1 Centre de recherche, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, PQ, Canada
2 Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russian Federation
3 Department of Medicine, University of Chicago, Chicago, IL, USA
This study examined the relative impact of Na+/K+-pump and Na+,K+,2Cl- cotransport in the regulation of the volume of human lung fibroblasts. Inhibition of the Na+/K+-pump by ouabain or of Na+,K+,2Cl- cotransport by bumetanide for 24 hours attenuated the rate of K+ (86Rb) influx in human lung fibroblasts from (1537 ± 124) cpm/well in control cells to (695 ± 14) and (522 ± 14) cpm/well in ouabain- or bumetanide-treated cells, respectively, whereas simultaneous addition of both inhibitors decreased the rate of K+ influx to (180 ± 8) cpm/well. Inhibition of either the Na+/K+-pump or of Na+,K+,2Cl- cotransport did not significantly change the volume of human lung fibroblasts, measured as 14C-urea available space, whereas simultaneous blockade of both ion transporters resulted in a 2-fold elevation of cell
volume (table). Thus, our results demonstrate for the first time that both Na+/K+-pump and Na+,K+,2Cl- cotransport contribute to cell volume control in human lung fibro-blasts.
Effect of ouabain and bumetanide on the volume of human lung fibroblasts
+ Cell volume
ml per mg protein pl per cell
None (control) 0.79 ± 0.12 0.23 ± 0.04
Ouabain, 100 nM 0.97 ± 0.14 0.26 ± 0.04
Bumetanide, 10 ^M 0.62 ± 0.01 0.22 ± 0.01
Ouabain + bumet-
anide 1.37 ± 0.13* 0.43 ± 0.04*
* p < 0.05 as compare to controls.
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Бюллетень сибирской медицины, 2013, том 12, № 4, с. 24-68
