Hypoperfusion of cerebral cortex in renal hypertensive rats

Morphometric and physiological measurements in the parietal cortex of rats with 2-kidney-1-clip renal hypertension and their normotensive controls indicated a 23% increase in capillary bed volume accompanied by a 32% reduction in the rate of cortical blood flow in the renal hypertensive animals. From these measures, we estimated an 83% increase in the duration of blood transit through the cortical capillary network of renal hypertensive rats, a new expression of altered microvascular function in the brain of this hypertensive model. The rate of glucose utilization in the cerebral cortex of renal hypertensive animals was not different from that observed for normotensive animals. Thus, for capillary networks in cerebral cortex of renal hypertensive rats, we demonstrated markedly reduced rates of perfusion independent of tissue metabolic factors, despite expansion of capillary bed volume.