Related Experiment Videos
Increased erythrocyte aggregation in spontaneously hypertensive rats
D Lominadze1, I G Joshua, D A Schuschke
1Center for Applied Microcirculatory Research and Department of Physiology and Biophysics, University of Louisville, Kentucky 40292, USA.
American Journal of Hypertension
|July 31, 1998
Summary
Increased red blood cell (RBC) aggregation and plasma viscosity occur early in hypertension development, even before significant blood pressure elevation. These rheologic changes may be linked to elevated fibronectin levels in genetically hypertensive rats.
Area of Science:
- Cardiovascular Physiology
- Hypertension Pathophysiology
- Blood Rheology
Background:
- Alterations in red blood cell (RBC) aggregation and plasma viscosity significantly impact blood rheology, increasing peripheral vascular resistance in hypertension.
- Existing research offers substantial insight into hypertension's pathophysiology, but the temporal relationship between rheologic changes and blood pressure elevation requires further investigation.
Purpose of the Study:
- To investigate whether increased RBC aggregability and plasma viscosity precede or coincide with the development of elevated arterial blood pressure.
- To analyze the role of plasma proteins, specifically fibrinogen and fibronectin (FN), in early hypertension.
Main Methods:
- Studied RBC aggregation and plasma viscosity in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats at 3 and 12 weeks of age.
- Measured plasma concentrations of fibrinogen and fibronectin (FN) in both rat groups and age points.
- Correlated rheologic parameters with arterial blood pressure measurements.
Main Results:
- RBC aggregability and plasma viscosity were elevated in both young and mature SHR compared to WKY controls.
- While mature SHR showed increased mean arterial and diastolic pressures, young SHR exhibited only significantly elevated diastolic pressure.
- Plasma fibronectin (FN) was significantly higher in both young and mature SHR, whereas fibrinogen increased only in mature SHR.
Conclusions:
- Increased RBC aggregability and plasma hyperviscosity are present in the early stages of hypertension development, preceding significant increases in mean arterial blood pressure.
- Elevated plasma fibronectin (FN) may play a crucial role in these early rheologic alterations.
- These findings highlight the importance of considering rheologic property changes and their underlying mechanisms during early hypertension development.