CENTRO DE INVESTIGACIONES CARDIOVASCULARES "DR. HORACIO EUGENIO CINGOLANI"
Unidad Ejecutora - UE
Cl-/HCO3- bicarbonate exchange activity in fMLP-stimulated human neutrophils
GIAMBELLUCA MIRIAM S; GENDE OSCAR A
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
ACADEMIC PRESS INC ELSEVIER SCIENCE
Lugar: Amsterdam; Año: 2011 vol. 409 p. 567 - 571
a b s t r a c t It is well known that chemotactic agents active Na+/H+ exchanger, increasing intracellular pH of neutrophils, but their effect on bicarbonate transporters have not been established yet. To study the effect of fMLP on the activity of Cl/HCO+/H+ exchanger, increasing intracellular pH of neutrophils, but their effect on bicarbonate transporters have not been established yet. To study the effect of fMLP on the activity of Cl/HCO3 exchange, the rate of pH recovery after acute Cl readmission in cell subjected to an alkaline load by CO2 washout in a Cl-free medium was measured. The activity of the exchanger was reduced to 72% of control when cells were pre-incubated for 5 min with 0.1 lM fMLP and reached 48% of control in steady state after acute exposure. After extracellular bicarbonate or TMA addition the rate recovery of intracellular pH was reduce at 72% and at 84%, respectively. The inhibitory effect on the intracellular pH recovery was not affected by blockers of Na+/H+ exchange. We conclude from these studies that an increase of pHi produced for this chemotactic agent is facilitated by the simultaneous activation of Na+/H+ exchange and inhibition of Cl/HCOexchange,