losartan-potassium and Hyperemia

Recombinant human erythropoietin (rHuEPO) has been used as a performance-enhancing agent by athletes in a variety of sports. The resulting increase in hematocrit levels leads to increased blood viscosity and can affect blood flow, potentially increasing the athlete's risk of developing health complications. However, the actual effects of using rHuEPO on microvascular blood flow and post-occlusive reactive hyperemia are currently unknown. We therefore evaluated the effect of rHuEPO on the cutaneous microcirculation in well-trained cyclists using laser speckle contrast imaging (LSCI). This study was part of a randomized, double-blind, placebo-controlled, parallel trial designed to investigate the effects of rHuEPO in 47 well-trained adult cyclists (age 18-50 years). Subjects received a weekly dose of either rHuEPO or placebo for 8 weeks, and LSCI was performed at baseline, after a maximal exercise test in week 6, and before maximal exercise in week 8. Endpoints included basal blood flux, maximum post-occlusion reperfusion, and time to return to baseline. Despite an increase in hematocrit levels in the rHuEPO-treated group, we found no statistically significant difference in microvascular function measured between the rHuEPO-treated group and the placebo group. Our results suggest that the increased hematocrit levels in rHuEPO-treated well-trained cyclists are not associated with changes in microvascular blood flow or post-occlusive reactive hyperemia measured using LSCI.

Topics: Adult; Erythropoietin; Exercise; Hematocrit; Humans; Hyperemia; Male; Microcirculation; Middle Aged; Recombinant Proteins; Skin

In a previous randomized controlled trial, the authors demonstrated that acute erythropoietin (EPO) therapy reduced severe vasospasm and delayed ischemic deficits (DIDs) following aneurysmal subarachnoid hemorrhage. In this study, the authors aimed to investigate the potential interaction of neurovascular protection by EPO with age, sepsis, and concurrent statin therapy.. The clinical events of 80 adults older than 18 years and with < 72 hours of aneurysmal subarachnoid hemorrhage, who were randomized to receive 30,000 U of intravenous EPO-beta or placebo every 48 hours for a total of 3 doses, were analyzed by stratification according to age (< or > or = 60 years), sepsis, or concomitant statin therapy. End points in the trial included cerebral vasospasm and impaired autoregulation on transcranial Doppler ultrasonography, DIDs, and unfavorable outcome at discharge and at 6 months measured with the modified Rankin Scale and Glasgow Outcome Scale. Analyses were performed using the t-test and/or ANOVA for repeated measurements.. Younger patients (< 60 years old) or those without sepsis obtained benefits from EPO by a reduction in vasospasm, impaired autoregulation, and unfavorable outcome at discharge. Compared with nonseptic patients taking EPO, those with sepsis taking EPO had a lower absolute reticulocyte count (nonsepsis vs sepsis, 143.5 vs. 105.8 x 10(9)/L on Day 6; p = 0.01), suggesting sepsis impaired both hematopoiesis and neurovascular protection by EPO. In the EPO group, none of the statin users suffered DIDs (p = 0.078), implying statins may potentiate neuroprotection by EPO.. Erythropoietin-related neurovascular protection appears to be attenuated by old age and sepsis and enhanced by statins, an important finding for designing Phase III trials.

Topics: Age Factors; Aneurysm, Ruptured; Clinical Trials, Phase II as Topic; Double-Blind Method; Drug Synergism; Drug Therapy, Combination; Erythropoietin; Glasgow Outcome Scale; Hematopoiesis; Homeostasis; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hyperemia; Intracranial Aneurysm; Middle Aged; Neuroprotective Agents; Randomized Controlled Trials as Topic; Recombinant Proteins; Sepsis; Subarachnoid Hemorrhage; Ultrasonography, Doppler, Transcranial; Vasospasm, Intracranial

Haemodialysis patients have abnormal blood vessels, and increased morbidity from vascular causes, effects which may potentially be enhanced by erythropoietin (EPO) therapy.. Microcirculatory blood flow was assessed using a laser-Doppler flowmeter in a group of 19 haemodialysis patients before and during treatment with recombinant human (EPO).. Haemodialysis patients had significantly impaired microcirculatory blood flow under both basal (25 degrees C) and hyperaemic (44 degrees C) conditions by comparison with 19 normal controls (baseline flow, median and range: patients 1.54 (0.28-2.54) volts, controls 3.39 (0.94-5.23) volts, p < 0.001 Mann Whitney U Test; hyperaemic flow, patients 2.69 (1.08-3.82) volts, controls 3.81 (1.32-8.00) volts, p < 0.001). There was no significant influence on microcirculatory blood flow of patient age, duration of haemodialysis, short-term EPO therapy (subcutaneous or intravenous), therapy with a calcium-channel blocker/vasodilator (nifedipine), or radiological evidence of vascular calcification.. Haemodialysis patients have an abnormal peripheral microvasculature, which may be relevant to their increased risk of ischaemic tissue damage and poor wound healing.

Topics: Anemia; Antihypertensive Agents; Blood Flow Velocity; Calcium Channel Blockers; Case-Control Studies; Erythropoietin; Female; Fingers; Humans; Hyperemia; Kidney Failure, Chronic; Laser-Doppler Flowmetry; Male; Microcirculation; Middle Aged; Nifedipine; Recombinant Proteins; Renal Dialysis; Skin

Topics: Animals; Body Weight; Depression, Chemical; Erythropoiesis; Erythropoietin; Female; Hematocrit; Hematologic Diseases; Hyperemia; Immune Sera; Iron; Iron Isotopes; Rats