R. Scatena et al., EFFECTS OF GEMFIBROZIL ON THE OXYGEN-TRANSPORT PROPERTIES OF ERYTHROCYTES, British journal of clinical pharmacology, 39(1), 1995, pp. 25-30
1 In the present study we have investigated the effects of the relativ
ely low plasma concentrations of gemfibrozil (GFZ) found in clinical p
ractice on the oxygen dissociation curve (ODC) of erythrocytes. 2 ODCs
were measured at 30 degrees C and 37 degrees C and at pH 7.4: a) both
on HbA solution and erythrocytes incubated in vitro with gemfibrozil
and clofibric acid; b) on erythrocytes from healthy volunteers treated
with a single oral dose of gemfibrozil. 3 These experiments showed a
significant drug-induced shift of the ODC towards lower O-2, affinity
values without any significant modification of metabolic parameters of
erythrocytes such as intracellular pH and intraerythrocytic levels of
ATP and DPG. 4 In our experimental conditions gemfibrozil appears to
lower both in vitro and in vivo, the partial pressure of oxygen requir
ed to give 50% of the haemes saturated with oxygen (P-50) Of erythrocy
tes from the control value of 24 +/- 0.5 mm Hg to 29 +/- 0.5 mm Hg (me
an +/- s.d.; P < 0.02 by ANOVA). 5 These data clearly indicate that th
erapeutic doses of gemfibrozil may influence the oxygen transport prop
erties of red cells. This effect could have relevant pharmacological a
nd toxicological implications.