RT Journal Article SR Electronic T1 Rapid and reversible astrocytic reaction to afferent activity blockade in chick cochlear nucleus JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 1001 OP 1009 DO 10.1523/JNEUROSCI.12-03-01001.1992 VO 12 IS 3 A1 KS Canady A1 EW Rubel YR 1992 UL http://www.jneurosci.org/content/12/3/1001.abstract AB We describe here rapid proliferation of astrocytic processes immunoreactive for glial fibrillary acidic protein (GFAP) in the chick cochlear nucleus following blockade of action potentials in the afferent nerve. Unilateral eighth nerve activity blockade was achieved through intralabyrinthine injection of TTX. Within 1 hr of activity blockade, a 56% increase in area density of GFAP-immunoreactive processes was found in the ipsilateral cochlear nucleus as compared to the contralateral side of the brain. This increase reached 152% by 3 hr. When eighth nerve activity was allowed to recover and animals were studied 1 week after TTX injection, no difference was found in GFAP immunoreactivity between the ipsilateral and contralateral cochlear nuclei. This is the first report of a glial reaction to documented neuronal inactivity in the absence of neuropathology. These results indicate that neuronal activity may regulate the structure of astrocytic processes.