Hemorheology in spontaneous animal endocrinopathies

Plasma proteins and lipid profile influence whole blood fluidity through changes in plasma viscosity, red cell aggregability and deformation. In diseases like Cushing syndrome (CS) and diabetes mellitus (DM) plasma concentrations of fibrinogen, cholesterol, and triglycerides are increased, and, thus, blood rheology might be affected. Our aim was to determine parameters of blood fluidity in 26 dogs with spontaneous CS and DM. Ten dogs (CS) and 16 dogs (DM) showed typical signs of the respective disease, and their blood was tested for whole blood viscosity (WBV, at 37 degrees C, LS30, Contraves, Zurich, Switzerland) at two shear rates (WBV(0.7 s(-1)); WBV(94 s(-1))), erythrocyte aggregation (AI, LS30), and plasma viscosity (PV, at 21 degrees C, OCR-D, Paar, Graz, Austria). Plasma fibrinogen, cholesterol, and triglyceride concentration was increased in both groups of patients, plasma total protein was elevated only in dogs with DM. Plasma viscosity and erythrocyte aggregation was increased markedly in all dogs, however, WBV(0.7 s(-1)) was increased only in dogs with DM, whereas dogs with CS showed a decrease in WBV(0.7 s(-1)) despite the rise in fibrinogen and erythrocyte aggregation. Hypertension and microvascular complications have been demonstrated in patients with CS and DM. These effects are multifactorial, and it seems possible that changes in blood rheology contribute to these disturbances.