Platelet activation in patients with sickle disease, hemolysis-associated pulmonary hypertension, and nitric oxide scavenging by cell-free hemoglobin.

ABSTRACT: Increased platelet activation is recognized in patients with sickle cell disease (SCD), but its pathogenesis and clinical relevance remain uncertain. Pulmonary arterial hypertension (PAH), an important complication of SCD, is characterized by a proliferative pulmonary vasculopathy, in situ thrombosis, and vascular dysfunction related to scavenging of nitric oxide (NO) by hemoglobin released into blood plasma during intravascular hemolysis. We investigated links between platelet activation, PAH and NO scavenging in patients with SCD. Platelet activation marked by activated fibrinogen receptor correlated to the severity of PAH (r = 0.58, P < .001) and to laboratory markers of intravascular hemolysis, such as reticulocyte count (r = 0.44, P = .02). In vitro exposure of platelets to pathologic

SUBMITTER: Villagra J 

PROVIDER: S-EPMC1976348 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature