title: [Hemorheological alterations in hypertensive patients].
abstract: The aim of this study was to investigate the blood viscosity profile and to evaluate the influence of plasmatic (fibrinogen) and cellular (erythrocyte aggregation) factors in a group of hypertensive patients, compared with a normotensive group. We worked with anticoagulated blood of both non diabetic hypertensive patients (n=31), and healthy individuals (n=40). The plasmatic viscosity and whole blood determination were obtained with a cone-plate viscometer. Erythrocyte aggregation was studied by microscopical observation and quantified by an Aggregate Shape Parameter (ASP), defined as the relation projected area/perimeter. Fibrinogen was determined by the Clauss method with a coagulometer. A comparison between these groups led us to assert that whole blood viscosity was significantly higher in hypertensive patients than in the controls at all shear rates. Plasma viscosity values only showed significant differences between both groups at low shear rate (1.15 a 11.56 seg(-1)). The hypertensive patients showed irregular and amorphous aggregates so that ASP appeared significantly higher (p< 0.001) in patients with hypertension (0.69 +/- 0.11) than in healthy subjects (0.25 +/- 0.12). Fibrinogen appeared slightly higher (p<0.01) in the hypertensive group than in the normal group. Several hemorheological parameters play important roles in the pathogenesis of hypertension. Among these factors, several hemorheological parameters could be altered in hypertension (hematocrit, plasma fibrinogen level, erythrocyte deformability and aggregability, plasma and whole blood viscosity). An increased RBC aggregation has been identified as an important factor responsible for disturbing blood rheological behavior in the microcirculation. The present study demonstrates an abnormal erythrocyte aggregation, which was detected by increased ASP values that could be responsible for vascular complications in hypertension.
authors.affiliation: Departamento de Bioquímica Clínica, Facultad de Ciencias Bioquímicas y Farmacéuticas (Instituto de Física CONICET-UNR). pforesto@arnet.com.ar
authors.forename: Patricia
authors.initials: P
authors.lastname: Foresto
authors.forename: Mabel
authors.initials: M
authors.lastname: D'Arrigo
authors.forename: Fernando
authors.initials: F
authors.lastname: Filippini
authors.forename: Roberto
authors.initials: R
authors.lastname: Gallo
authors.forename: Liliana
authors.initials: L
authors.lastname: Barberena
authors.forename: Liliana
authors.initials: L
authors.lastname: Racca
authors.forename: Juana
authors.initials: J
authors.lastname: Valverde
authors.forename: Rodolfo J
authors.initials: RJ
authors.lastname: Rasia
mesh_terms: D000328:Adult; D000368:Aged; D001809:Blood Viscosity / Q000502:physiology; D004903:Erythrocyte Aggregation / Q000502:physiology; D005260:Female; D005340:Fibrinogen / Q000502:physiology; D018056:Hemorheology; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged
chemical_list: D005340:Fibrinogen