Cyclosporin A-associated changes in red blood cell membrane composition, deformability, blood and plasma viscosity in rats.

Most of the studies concerning the effects of cyclosporin A (Cs A) on red blood cell (RBC) rheology were carried out in human transplant recipients who may still have residual insufficiency and concomitant administration of other immunosuppressive and antihypertensive drugs. The aim of this study is to evaluate the effects of Cs A on red cell rheology and membrane composition in nontransplant healthy rats. Female Wistar albino rats were divided into two groups of 10 animals each. Rats received 10 mg/kg Cs A, i.p. or saline for 4 weeks. Cs A administration significantly increased the RBC deformability, and plasma and blood viscosity (p < 0.001, p < 0.01 and p < 0.01, respectively). Cs A administration to the rats increased RBC membrane cholesterol (CHO) levels and the CHO/phospholipid (PL) ratio significantly (p < 0.01 and p < 0.05, respectively) but did not change RBC membrane proteins and membrane PL levels. These results suggest that Cs A changes the rheological functions of RBC and lipid content of RBC membrane in healthy rats and thereby it may play an important role in the regulation of microcirculation.