[The effect of fluoride ions on the activity of the platelet sodium-proton exchanger: a preliminary report].
BACKGROUND
The sodium-proton exchanger (NHE) is a transmembrane protein present in cell membranes of all species studied so far. It operates as an antiporter removing protons from the cell in exchange for sodium ions. Various factors are known to affect the activity of NHE. The aim of this work was to study the effect of fluoride on the activity of NHE in human platelets.


METHODS
Platelets obtained from healthy volunteers were incubated for 5, 10, 15, or 20 minutes in sodium fluoride (NaF) at a concentration of 2.5, 5.0, 7.5, or 10 mmol/L. NHE activity in platelets exposed to NaF was measured with a spectrophotometric method and was compared with activity in control platelets unexposed to NaF.


CONCLUSIONS
Mean NHE activity in control platelets was 5.22+/-1.84 /PLTC/min. NaF at 2.5 mmol/L reduced NHE activity producing a minimum after 10 min of incubation whereupon activity increased reaching 5.44 +/- 3.97/ PLTC/min after 20 min of incubation. NaF was inhibitory at higher concentrations and the following NHE activities were noted: 4.37 +/- 1.66 /PLTC/min (p = 0.006235) at 5.0 mmol/L, 4.05 +/-1.15 /PLTC/min (p = 0.000253) for 7.5 mmol/L and 4.25+/-1.40 /PLTC/min (p = 0.008891) for 10 mmol/L.
Gassowska
Magdalena
M
Zakład Biochemii, Katedra Biochemii i Chemii Medycznej Pomorskiej Akademii Medycznej al. Powstafic6w Wlkp. 72, 70-111 Szczecin.
Dołegowska
Barbara
B
Chlubek
Dariusz
D
D001792:Blood Platelets / Q000187:drug effects*; D048429:Cell Size / Q000187:drug effects; D005459:Fluorides / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D017923:Sodium-Hydrogen Exchangers / Q000187:drug effects*; D013053:Spectrophotometry
D017923:Sodium-Hydrogen Exchangers; D005459:Fluorides