Characterization of Na+/H+ exchange in sheep rumen epithelial cells kept in primary culture.
The study aimed at testing whether Na+/H+ exchange activity is maintained during isolation and cultivation of rumen epithelial cells (REC) and whether Na+/H+ exchange is altered during proliferation and differentiation. REC were isolated from sheep rumen epithelium by fractional trypsinization and further cultivated for up to 21 days. Characteristics of Na+ uptake into cultured REC were the same as previously described for the Na+/H+ exchange in the intact rumen epithelium. Na+ uptake was increased by intracellular acidification and was inhibited by high doses of amiloride. Amiloride inhibited 3H-thymidine incorporation into REC at concentrations similar to those found for the inhibition of Na+ uptake. Fetal calf serum, a growth factor, stimulated amiloride-sensitive Na+ uptake. We therefore conclude that cultured rumen epithelial cells express Na+/H+ exchange and that the activity of the exchange is at least correlated to the intensity of proliferation.
Gäbel
G
G
Department of Veterinary Physiology, Free Univ. of Berlin, Germany.
Gálfi
P
P
Neogrády
S
S
Martens
H
H
D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D002455:Cell Division; D002478:Cells, Cultured; D004232:Diuretics / Q000494:pharmacology; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D012417:Rumen / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D012756:Sheep / Q000378:metabolism*; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism*
D004232:Diuretics; D017923:Sodium-Hydrogen Exchangers; D000584:Amiloride