Erythropoietin‐induced rheological changes of rat erythrocytes

Abstract

Summary. The effects of recombinant human erythropoietin (rhEPO) on red blood cell (RBC) rheological properties were investigated in rats. Rats received intramuscular injections of 150 U/kg/d rhEPO for 5 d, following which blood samples were obtained 1, 5 or 10 d later. RBC deformability was assessed by determining cell transit times through 5-mm micropores (CTA) and RBC shape recovery time constants via photometry, aggregation in plasma and dextran was measured by photometry and RBC electrophoretic mobility was determined in a cylindrical electrophoresis system. RBC aggregation was found to be significantly decreased on day 5 after rhEPO treatment (P , 0´05), yet was unchanged from control on days 1 and 10. Mean RBC micropore transit times remained unchanged, but the distributions of transit times were altered; compared with control, the 5th percentiles on both days 1 and 5 were decreased and the 95th percentile on day 1 was elevated. Electrophoretic mobility of RBCs in phosphate-buffered saline was significantly increased on day 5 after rhEPO treatment (P , 0´05), with mobility measurements in dextran 500 (MW 500 kDa) solutions suggesting that the cells' surface properties related to the formation of a`depletion layer' may be altered on day 1. These results indicate that the rheological behaviour of RBC as a consequence of rhEPO treatment are temporal and are affected by the presence of reticulocytes as well as by the average age of the circulating cells.

Oxidative stress-associated shape transformation and membrane proteome remodeling in erythrocytes of end stage renal disease patients on hemodialysis

“…Previous studies have reported significant differences in the mechanical properties and rheological behavior of RBCs as a consequence of erythropoietin treatment [25]. In our study, the response to erythropoietin was well reflected in the hematological profile and the relatively high value of the MCV index (Table 1).…”

Repeated Low-dose of Erythropoietin is Associated with Improved Left Ventricular Function in Rat Acute Myocardial Infarction Model

“…In this group, hematocrit levels were significantly higher compared to the other treated arms. High hematocrit values are known to adversely affect red blood cells rheological properties [35]. In addition, elevated hematocrit levels are associated with down-regulation of nitric oxide synthesis [36], increased blood pressure [37], activation of the tissue endothelin system [38] and increased in situ thrombosis [39,40].…”

EPO or PlacEPO? Science versus Practical Experience

“…Finally, let me mention a paper that we published about 15 years ago. We treated rats with rHuEPO and noticed a significant decrease in erythrocyte aggregation explained by a concomitant rise in the surface charge of RBCs 22 . There was also a change in RBC deformability suggesting that EPO alters inherent RBC properties.…”