Stroke, Vol 11, 622-628, Copyright © 1980 by American Heart Association
Histochemical changes of brain dopamine in an acute stage of cerebral ischemia in gerbils
A Ahagon, M Ishikawa and H Handa
The fluorescence histochemical method of Falck et al. was applied to 40
gerbil brains after ligation of a unilateral common carotid artery to
investigate alterations of brain dopamine in the acute stage of cerebral
ischemia. The distribution of dopaminergic terminals and cell bodies in
gerbils is the same as in other mammals. On the ligated side after one hour
of ischemia, diffuse green fluorescence of dopaminergic terminals showed
only a slight decrease in intensity when compared to the nonligated side.
But white matter and bundles of myelinated fibers adjacent to and in the
dopamine-rich regions had an intense green fluorescence in contrast to the
non-ligated side where they are normally non-fluorescent. This is
considered to indicate the extraneuronal leakage and diffusion of dopamine.
The intensity of extraneuronal green fluorescence was especially high in
glial cells. Occasionally, there was also an unusual green fluorescence in
the lumen of small vessels in dopamine-rich regions on the ligated side.
Dopaminergic cell bodies in the substantia nigra on the ligated side
revealed a conspicuous reduction in the fluorescence intensity in severely
affected cases. After 2 or 3 hours of ischemia, there was a marked
reduction or disappearance of the diffuse green fluorescence on the ligated
side. This may be attributed in part to further diffusion of leaked
dopamine.