Effect of ticlopidine hydrochloride on erythropoietin-induced rise in blood pressure in patients on maintenance hemodialysis

Prevention of Erythropoietin-Associated Hypertension

Hypertension is the most significant complication from treatment with erythropoietin (Epo). Can Epo-induced hypertension be eliminated? We examined systemic and local effects of our genetically engineered products, Epo-binding protein (Epo-bp) and anti–Epo-bp antibodies, on randomly assigned Sprague–Dawley rats at midnight, 4 am , 8 am , noon, 4 pm , and 8 pm . Blood pressure, hematocrit, and body weight were measured immediately before and after the completion of a 4-week, twice-weekly course of Epo (50 U/kg), Epo-bp, anti–Epo-bp antibodies, or physiological saline injections. Epo treatment increased hematocrit markedly overall as compared with the saline, Epo-bp, and anti–Epo-bp antibody groups (0.616 versus 0.427, 0.439, and 0.441, respectively) and at each of the 6 test times (all P <0.0001). Epo-bp and anti–Epo-bp antibody treatment with Epo had almost no effect on the Epo-induced hematocrit increase (0.616 versus 0.580 or 0.591, respectively). Circadian blood pressures for Epo versus saline, Epo-bp, and anti–Epo-bp antibody groups were 136.2±2.3 versus 116.2±1.7, 118.4±2.1, and 116.6±2.1 mm Hg, respectively (each P <0.0001). Significantly increased blood pressure was detected at noon, 4 pm , 8 pm , and midnight in Epo treatment. When Epo was given with Epo-bp or anti–Epo-bp antibodies, blood pressure was maintained at similar levels as in saline treatment (each P <0.0001) as compared with Epo treatment alone. Overall, body, brain, and heart weights were significantly lower in Epo treatment than those of other groups. Thus, Epo-bp and anti–Epo-bp antibodies eliminate Epo-induced hypertension without affecting hematocrit and blood volume.

Mean arterial pressure and pulse pressure are associated with different clinical parameters in chronic haemodialysis patients

The mean arterial pressure (MAP) usually serves as an expression of blood pressure in patients on chronic haemodialysis (PCHD), instead of using solely systolic or diastolic pressure. Pulse pressure (PP) has been recognized as an important correlate of mortality in PCHD. We conducted this study in order to demonstrate clinical and biochemical determinants and variability of predialysis and postdialysis MAP and PP values. A total of 136 single haemodialysis (HD) treatments in 23 subjects (PCHD, 11 male and 12 female patients) were processed during 15 months. MAP before HD was in negative correlation with haemoglobin (P<0.001) and body mass index (BMI) (P<0.001), and in positive correlation with weekly erythropoietin dosage (P=0.017). MAP after HD was in negative correlation with haemoglobin (P<0.001), ultrafiltration per HD (P=0.015), and BMI (P=0.001), and in positive correlation with weekly erythropoietin dosage (P=0.003). PP before HD was in negative correlation with parathyroid hormone (PTH) level (P=0.020), haemoglobin (P<0.001), ultrafiltration per HD (P=0.001), and years on the chronic HD treatment (P=0.001), and in positive correlation with weekly erythropoietin dosage (P<0.001) and age (P<0.001). PP after HD was in significant negative correlation with PTH (P=0.015), haemoglobin (P=0.005), ultrafiltration per HD (P<0.001), BMI (P=0.003), and in positive correlation with weekly erythropoietin dosage (P<0.001) and age (P=0.004). Multiple regression analyses unveiled the strongest and negative correlations between MAP before HD and BMI (beta=-0.37, P=0.01); MAP after HD and haemoglobin (beta=-0.36, P=0.01); PP after HD and ultrafiltration/body weight ratio (beta=-0.41, P<0.001). The strongest and positive correlation was found between PP before HD and erythropoietin dosage per week (beta=0.51, P&<0.001). In conclusion, our findings support the assumption that PP and MAP are associated with different clinical parameters. PP values have advantages as the method of blood pressure expression.