Na+, K+-ATPase activity and subunit isoform protein abundance: effects of antenatal glucocorticoids in the frontal cerebral cortex and renal cortex of ovine fetuses.
We examined the effects of single and multiple maternal glucocorticoid courses on cerebral cortical (CC) and renal cortical (RC) Na(+),K(+)-ATPase activity and protein isoform abundance in fetal sheep. Ewes received four dexamethasone or placebo injections in the single course (SC) groups, and the same treatment once a week for five-weeks in the multiple course (MC) groups. CC Na(+),K(+)-ATPase a(2)-abundance was higher (P<0.05) and beta(2)-abundance lower in the SC dexamethasone than placebo group, but Na(+),K(+)-ATPase activity did not change. CC Na(+),K(+)-ATPase activity, a(1)-, beta(1) -, and beta(2)-abundance were lower in the MC dexamethasone than placebo group, but a(2)- and a(3)-abundance did not change. Both dexamethasone courses did not affect CC cell number. RC Na(+),K(+)-ATPase activity, a(1)- and beta(1) -abundance were higher in the MC dexamethasone than placebo group, but did not change in the SC dexamethasone group. We conclude MC, but not a SC of dexamethasone, affect fetal cerebral and renal Na(+),K(+)-ATPase, and MC result in differential effects on Na(+),K(+)-ATPase in these organs.
Mehter
Najma S
NS
Warren Alpert Medical School of Brown University, Department of Pediatrics, Women & Infants' Hospital of Rhode Island, Providence, Rhode Island 02905, USA.
Sadowska
Grazyna B
GB
Malaeb
Shadi N
SN
Stonestreet
Barbara S
BS
D000818:Animals; D002452:Cell Count; D002540:Cerebral Cortex / Q000187:drug effects* / Q000196:embryology / Q000201:enzymology; D003907:Dexamethasone / Q000008:administration & dosage* / Q000378:metabolism; D004334:Drug Administration Schedule; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage* / Q000378:metabolism; D007273:Injections, Intramuscular; D007672:Kidney Cortex / Q000187:drug effects* / Q000196:embryology / Q000201:enzymology; D008431:Maternal-Fetal Exchange; D009474:Neurons / Q000187:drug effects / Q000201:enzymology; D011247:Pregnancy; D021122:Protein Subunits; D012756:Sheep; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*
D005938:Glucocorticoids; D021122:Protein Subunits; D003907:Dexamethasone; D000254:Sodium-Potassium-Exchanging ATPase