Fig. 3.
Effect of exposure to reduced O2 tension on ATP release from erythrocytes of healthy humans (n = 7) and humans with DM2 (n = 10). In a tonometer, isolated erythrocytes (hematocrit 20%) were exposed to gas mixtures containing either 15% O2, 6% CO2, and balance nitrogen (Po2 = 107 ± 5 mmHg) or 0% O2, 6% CO2, balance nitrogen (Po2 = 10 ± 1 mmHg). ATP release was determined after a 30-min equilibration with 15% O2 and 10 min after exposure to 0% O2. In separate studies, type 2 diabetes erythrocytes were exposed to identical gas compositions in the absence and presence of the PDE3 inhibitor cilostazol (100 μM). Values are means ± SE. *Greater than respective normoxia (15% O2) value (P < 0.05); †different from respective normoxia value and from DM2 erythrocytes in the absence of cilostazol. RBCs, red blood cells.