[Nocigenic changes in the blood viscosity indices of rats]

One-minute subcutaneous nociceptive stimulation increased arterial pressure by 15-20 mm Hg in Wistar rats. The 20-min. stimulation altered rheological properties of the blood: the hematocrit, the plasma viscosity and protein concentration, the erythrocyte aggregation velocity, the utmost tension of shift, and the viscosity of the blood standardized by hematocrit--all these parameters increased. These changes are rather unfavourable for flowing properties of the blood. The changes of the blood rheological properties were reflex-based, the problem of compensatory shifts is discussed.