FIGURE 2.

Impairment of erythrocyte filterability caused by 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH). Representative relationships of P(t)-Q(t) during continuous filtration using HEPES-buffered control saline and human erythrocyte suspensions obtained from healthy volunteers are presented. The hematocrit of erythrocyte suspension was 3.0%, and the pore size of the nickel mesh filter was uniformly 5.31 μm. The P(t)-Q(t) relationships correspond to the two passages of control saline (◯, ) and sequential passages of erythrocyte suspensions in preincubation (□, ■) and under the incubation with 50 mM AAPH at incubation times of 20 (△), 40 (▲), 60 (◇), 120 (◆), and 180 (X) min at 36°C, respectively. Linear P(t)-Q(t) relationships passing origin indicate filtration of control saline behaving as a Newtonian fluid. The superimposable linearity satisfies the reproducibility of this filtration system. Continuous filtration of erythrocyte suspensions before incubation produced linearity at a high-pressure region that is followed smoothly by the concaved curve at a low-pressure region that is compatible with non-Newtonian behavior. The P(t)-Q(t) curves shifted to the rightward according to the progression of incubation. Filterability of erythrocyte suspensions (%) was defined as Q(t) of suspension at P(t) of 100 mmH₂O (vertical dotted line) divided by Q(t) of saline at the same P(t). Marked suppression of erythrocyte filterability yields a no-flow phenomenon under the pressure of 70 mmH₂O (intercept pressure) 180 min after starting incubation [cited from Odashiro et al. (2014) with permission and minor modification].