The passage of blood-borne horseradish peroxidase into the amygdaloid area of the mouse brain

Abstract 

The passage of blood-borne horseradish peroxidase (HRP) into the amygdaloid area of the mouse brain was examined with light and electron microscopy. Staining reaction for HRP appeared in medial portions of the amygdaloid area, especially adjacent to the optic tract. Ultrastructural examination of some vessels in that area revealed that the staining reaction for HRP appeared in the perivascular space, the basal lamina, the cytoplasm or vesicular structures of the perivascular cells, vesicular profiles of the endothelial cell cytoplasm including abluminal pits and the adjacent extracellular space. These findings suggest that intravascular macromolecules can invade medial portions of the amygdaloid area of the mouse brain.