Foreign anion substitution for chloride in neonatal human red cells. Effect on cellular volume.
The effect of replacement of chloride by thiocyanate has been investigated in neonatal human red cells. On incubating these cells in isotonic SCN- medium, a rapid cellular swelling was observed, which was not evident in Cl- media. Incubation in hypertonic SCN- medium showed a rapid osmotic shrinkage followed by reswelling back to the initial volume. This regulatory volume increase was completed in a shorter time than in Cl- medium. Whole water accumulated by the cells in both experimental conditions can be accounted for by net Na+ uptake (twofold augmentation with respect to initial value). Amiloride inhibits specifically both cellular swelling and the Na+ content increase in these experimental conditions. Similar experiments in neonatal red cells incubated in NO3- media, as well as in adult red cells placed in NO3- or SCN- media, did not exhibit the same response. The findings suggest that the response of neonatal red cells in a SCN- containing media was mediated by activation of a Na+/H+ antiport mechanism.
Serrani
R E
RE
Catedra de Fisiologia, Fac. Ciencias Medicas UNR, Santa Fe, Rosario, Argentina.
Taborda
D
D
Zamero
M
M
Corch
J L
JL
D000328:Adult; D000584:Amiloride / Q000494:pharmacology; D000838:Anions; D002712:Chlorides / Q000097:blood*; D004912:Erythrocytes / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D006982:Hypertonic Solutions; D007038:Hypotonic Solutions; D007231:Infant, Newborn; D012964:Sodium / Q000097:blood; D017923:Sodium-Hydrogen Exchangers / Q000097:blood; D013861:Thiocyanates / Q000097:blood*
D000838:Anions; D002712:Chlorides; D006982:Hypertonic Solutions; D007038:Hypotonic Solutions; D017923:Sodium-Hydrogen Exchangers; D013861:Thiocyanates; D000584:Amiloride; D012964:Sodium; C031760:thiocyanate