Figure 7. Effects of N-ethylmaleimide (NEM) and 5HMF on the activity of KCC in red blood cells (RBCs) from patients with sickle cell disease (SCD).

RBCs were pre-incubated for 30 min with or without NEM (1 mm) and/or 5HMF (5 mm) after which they were diluted 10-fold into test tubes for measurement of K⁺ influx, all in the absence or presence of 5HMF (5 mm). KCC activity is defined as the K⁺ influx [calculated as mmol (l cells h)⁻¹ and measured at an extracellular [K⁺] of 7.5 mm] in the absence or presence of Cl⁻ (substituted with NO₃⁻). Ouabain (100 μm), bumetanide (10 μm) and clotrimazole (5 μm) were included in all experiments. Data are means ± s.e.m., n = 5. *P < 0.05 for RBCs in the absence versus presence of 5HMF.