Evans blue distribution in the rate brain after intracarotid injection with the blood-brain barrier intact and open to osmosis.

Evans blue was applied to 12 rats by way of intracarotid injection into the common carotid artery or internal carotid artery both with the blood-brain barrier intact and after its mannitol-induced osmotic opening. For each type of application, a histological picture of Evans blue propagation through the brain was obtained by means of fluorescence microscopy. An assessment was made of the overall intensity of staining, and the ratio was established of the intra:extra-cellular Evans blue distribution in the cortex and hippocampus of both hemispheres. The histological picture obtained on injecting Evans blue into the internal carotic artery two minutes after the blood-brain barrier opening with mannitol can be seen as morphological evidence of the fact that the substance thus applied does have an effect on cell homeostasis since the intracellular share of Evans blue distribution is considerable.