Na/K-ATPase assay in the intact mice lung subjected to perfusion.
BACKGROUND
Among the characteristics of acute respiratory distress syndrome (ARDS) is edema formation and its resolution depends on pneumocyte Na/K-ATPase activity. Increased concentration of oleic acid (OA) in plasma induces lung injury by targeting Na/K-ATPase and, thus, interfering in sodium transport.


RESULTS
Presently, we adapted a radioactivity-free assay to detect Na/K-ATPase activity in perfused lung mice, comparing the inhibitory effect of ouabain and OA. We managed to perfuse only the lung, avoiding the systemic loss of rubidium. Rb+ incorporation into lung was measured by inductively coupled plasma optical emission spectrometry (ICP OES) technique, after lung tissue digestion. Na/K-ATPase activity was the difference between Rb+ incorporation with or without ouabain. Lung Na/K-ATPase was completely inhibited by perfusion with ouabain. However, OA caused a partial inhibition.


CONCLUSIONS
In the present work the amount of incorporated Rb+ was greater than seen in our previous report, showing that the present technique is trustworthy. This new proposed assay may allow researchers to study the importance of Na/K-ATPase activity in lung pathophysiology.
Instituto Oswaldo Cruz, Laboratório de Imunofarmacologia, FIOCRUZ, 21040-900, Av Brasil 4365, Pavilhão Ozório de Almeida, Rio de Janeiro, RJ, Brazil. cassianofg@gmail.com.
Cassiano Felippe
CF
Gonçalves-de-Albuquerque
Patrícia
P
Burth
Adriana Ribeiro
AR
Silva
Isabel Matos Medeiros
IM
de Moraes
Flora Magno Jesus
FM
de Oliveira
Ricardo Erthal
RE
Santelli
Aline Soares
AS
Freire
Mauricio
M
Younes-Ibrahim
Hugo Caire
HC
de Castro-Faria-Neto
Mauro Velho
MV
de Castro-Faria
D000818:Animals; D057075:Enzyme Assays / Q000379:methods*; D008168:Lung / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D051379:Mice; D019319:Okadaic Acid / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology; D010477:Perfusion; D012413:Rubidium / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*
D019319:Okadaic Acid; D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase; D012413:Rubidium