CHLORIDE CONCENTRATIONS IN PLASMA, ERYTHROCYTES, AND LYMPHOCYTES INDICATING DIFFERENT CHLORIDE FLUXES - MEASUREMENTS USING SPQ AND COLORIMETRIC TITRATION

Plasmic and intracellular chloride concentrations were determined in 1 5 healthy subjects. Intracellular chloride measurements were performed in erythrocytes and in lymphocytes. Plasmic and erythrocytic chloride concentrations were measured by using colorimetric titration. The cap acitative regulation of intracellular chloride concentration in intact human lymphocytes, using the chloride sensitive fluorescence dye 6-me thoxy-1-(3-sulfonato-propyl)-quinolinum (SPQ), was measured. The fluor escence was measured at 433 nm with the excitation wavelength of 344 n m. Plasma chloride concentrations were measured 96.5 +/- 2.9 mmol/l, i n erythrocytes 69.2 +/- 1.8 mmol Cl-/l, and in lymphocytes 29.6 +/- 3. 8 mmol Cl-/l were measured. The results show intracellular chloride co ncentrations of erythrocytes and lymphocytes being significantly lower ed as compared to plasma chloride concentrations (p < 0.0001). It is c oncluded that due to different Cl- transport systems and fluxes in var ious cell types human Cl- handling is regulated.