[Effects of subacute hypoxia on alveolar epithelial ion transport in rats].
To study the effects of subacute hypoxia on alveolar epithelial ion transport, alveolar fluid clearance was measured in isolated fluid-filled rat lungs. After instillation of a solution containing about 5% bovine albumin, an increase in alveolar fluid clearance was measured over 2 hours. Alveolar fluid clearance was lower when rats were kept in hypoxic conditions (FiO2 = 0.1) for 48 hours. Neither 10(-5) M amiloride (a Na(+)-channel blocker) nor 10(-3) M ouabain (an inhibitor of Na(+)-K(+)-ATPase) inhibited fluid clearance in the hypoxia group, but they did in the normoxia group. These results indicate that subacute hypoxia may down-regulate both the Na(+)-channl and Na(+)-K(+)-ATPase, and thus decrease the absorption of excess alveolar fluid.
Suzuki
S
S
Department of Thoracic Surgery, Tohoku University, Miyagi, Japan.
Hoshikawa
Y
Y
Ono
S
S
Sakuma
T
T
Koike
K
K
Tanita
T
T
Fujimura
S
S
D000818:Animals; D001693:Biological Transport, Active; D001834:Body Water / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D000860:Hypoxia / Q000378:metabolism*; D017136:Ion Transport; D011650:Pulmonary Alveoli / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015222:Sodium Channels / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
D015222:Sodium Channels; D000254:Sodium-Potassium-Exchanging ATPase