M. Bergmann et al., EXPRESSION OF SYNAPTOPHYSIN IN SPROUTING NEURONS AFTER ENTORHINAL LESION IN THE RAT, Experimental Brain Research, 117(1), 1997, pp. 80-86
Expression of the synaptic vesicle protein synaptophysin was studied i
n lesion-induced sprouting neurons of the contralateral entorhinal cor
tex and in the contralateral dentate gyrus using immunocytochemistry a
t the light-and electron-microscopic level. Perikaryal immunoreactivit
y for synaptophysin was found between a and 10 days postlesion. Light
microscopy revealed that synaptophysin immunostaining was present in a
lmost all neurons of layers II and III of the contralateral medial ent
orhinal cortex. These neurons give rise to the sprouting, crossed temp
orodentate pathway. In addition, some hilar neurons of the contralater
al dentate gyrus, which are the parent cells of sprouting commissural
fibers, were immunostained for synaptophysin. Transient immunostaining
for synaptophysin was observed within cell bodies and dendrites, Addi
tionally, the cell bodies were outlined by immunoreactive puncta, iden
tified by electron microscopy as nerve terminals. Our results revealed
that sprouting neurons express the major synaptic vesicle protein syn
aptophysin during reactive synaptogenesis in a pattern that reflects b
iosynthesis and sorting of this protein as seen in developing neurons
during synapse formation.