Expression of GFAP in the striatum and its projection areas in response to striatal quinolinic acid lesion in rats.

Injection of quinolinic acid (QA) into the rat striatum is known to produce neuropathological and neurochemical features of Huntington's disease (HD). In the present study the astrocytic response two weeks following intrastriatal injection of either QA (240 nmol) or solvent (1 microliter) was examined using immunohistochemistry for GFAP. Striatal QA lesion resulted in a marked GFAP expression within the whole striatum which is due to neuronal degeneration. Furthermore, the reticular part of substantia nigra, globus pallidus and ventromedial thalamic nucleus revealed increases in GFAP expression without neuronal damage. As this remote astrocytic response is located only in striatal projection areas it seems to reflect transsynaptic changes in response to the lesion.