Expression of basic fibroblast growth factor in astrocytes at the site of cerebral lesions and edematous areas under chronic hypertension.

In an attempt to obtain information about changes of the basic fibroblast growth factor (bFGF) in the brain under chronic hypertensive condition, we studied immunohistochemically the distribution of bFGF in the brain of stroke-prone spontaneously hypertensive rats (SHRSP). In the control normotensive rats, only weak immunoreactivity for bFGF was demonstrated in nerve cells and some astrocytes. In SHRSP marked immunoreactivity was demonstrated in the densely packed reactive cells, particularly astrocytes, in and around cerebral lesions. Slightly increased reaction for bFGF was found in the nerve cells around lesions. Astrocytes in the white matter also showed immunoreactivity for bFGF, the localization of which corresponded very well with the site of edema. This finding indicates the possibility that brain edema expresses bFGF in astrocytes and possibly in nerve cells.