Abstract
Previous studies showed that ouabain-sensitive rubidium (86Rb+) uptake by rabbit lung epithelial cells increases at birth, followed by a more gradual postnatal increase, reaching adult values by age 30 days. To see whether these changes in ouabain-sensitive cation transport were the result of changes in Na+ pump number or turnover rate, we measured binding of [3H]ouabain and ouabain-sensitive 86Rb+ uptake by freshly isolated lung epithelial cells harvested from near-term fetal, newborn, and adult rabbits. Ouabain-sensitive 86Rb+ uptake by fetal cells was 1/4 that of newborn cells and 1/10 that of adult cells. The maximal number of ouabain binding sites (U(max)) was the same for fetal and newborn cells but almost threefold greater for adult cells. Na+ pump turnover rate, determined from ouabain-sensitive 86Rb+ uptake and U(max), was four times greater in newborn and adult cells than it was in fetal cells. Thus the increase in 86Rb+ uptake at birth could be explained by an increase in Na+-K+-adenosinetriphosphatase (ATPase) turnover rate, whereas the postnatal increase in 86Rb+ uptake could be accounted for by an increase in the amount of Na+-K+-ATPase per cell.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Lung Cellular and Molecular Physiology |
| Volume | 259 |
| Issue number | 6 3-3 |
| State | Published - 1990 |
| Externally published | Yes |
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Keywords
- alveolar epithelial cells
- ion transport
- lung maturation
- ouabain binding
- sodium pumps
ASJC Scopus subject areas
- Cell Biology
- Physiology
- Pulmonary and Respiratory Medicine
Cite this
Developmental differences in rabbit lung epithelial cell Na+-K+-ATPase. / Chapman, D. L.; Widdicombe, Jonathan; Bland, R. D.
In: American Journal of Physiology - Lung Cellular and Molecular Physiology, Vol. 259, No. 6 3-3, 1990.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Developmental differences in rabbit lung epithelial cell Na+-K+-ATPase
AU - Chapman, D. L.
AU - Widdicombe, Jonathan
AU - Bland, R. D.
PY - 1990
Y1 - 1990
N2 - Previous studies showed that ouabain-sensitive rubidium (86Rb+) uptake by rabbit lung epithelial cells increases at birth, followed by a more gradual postnatal increase, reaching adult values by age 30 days. To see whether these changes in ouabain-sensitive cation transport were the result of changes in Na+ pump number or turnover rate, we measured binding of [3H]ouabain and ouabain-sensitive 86Rb+ uptake by freshly isolated lung epithelial cells harvested from near-term fetal, newborn, and adult rabbits. Ouabain-sensitive 86Rb+ uptake by fetal cells was 1/4 that of newborn cells and 1/10 that of adult cells. The maximal number of ouabain binding sites (U(max)) was the same for fetal and newborn cells but almost threefold greater for adult cells. Na+ pump turnover rate, determined from ouabain-sensitive 86Rb+ uptake and U(max), was four times greater in newborn and adult cells than it was in fetal cells. Thus the increase in 86Rb+ uptake at birth could be explained by an increase in Na+-K+-adenosinetriphosphatase (ATPase) turnover rate, whereas the postnatal increase in 86Rb+ uptake could be accounted for by an increase in the amount of Na+-K+-ATPase per cell.
AB - Previous studies showed that ouabain-sensitive rubidium (86Rb+) uptake by rabbit lung epithelial cells increases at birth, followed by a more gradual postnatal increase, reaching adult values by age 30 days. To see whether these changes in ouabain-sensitive cation transport were the result of changes in Na+ pump number or turnover rate, we measured binding of [3H]ouabain and ouabain-sensitive 86Rb+ uptake by freshly isolated lung epithelial cells harvested from near-term fetal, newborn, and adult rabbits. Ouabain-sensitive 86Rb+ uptake by fetal cells was 1/4 that of newborn cells and 1/10 that of adult cells. The maximal number of ouabain binding sites (U(max)) was the same for fetal and newborn cells but almost threefold greater for adult cells. Na+ pump turnover rate, determined from ouabain-sensitive 86Rb+ uptake and U(max), was four times greater in newborn and adult cells than it was in fetal cells. Thus the increase in 86Rb+ uptake at birth could be explained by an increase in Na+-K+-adenosinetriphosphatase (ATPase) turnover rate, whereas the postnatal increase in 86Rb+ uptake could be accounted for by an increase in the amount of Na+-K+-ATPase per cell.
KW - alveolar epithelial cells
KW - ion transport
KW - lung maturation
KW - ouabain binding
KW - sodium pumps
UR - http://www.scopus.com/inward/record.url?scp=0025696754&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0025696754&partnerID=8YFLogxK
M3 - Article
C2 - 2175558
AN - SCOPUS:0025696754
VL - 259
JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
SN - 1931-857X
IS - 6 3-3
ER -