Electroconvulsive shock causes neuronal death in the mouse hippocampus: correlation of neurodegeneration and convulsive activity
Zarubenko, I.I.; Iakovlev, A.A.; Stepanichev, M.I.; Guliaeva, N.V.
Rossiiskii Fiziologicheskii Zhurnal Imeni I.M. Sechenova 90(3): 272-281
2004
ISSN/ISBN: 0869-8139 PMID: 15152563 Document Number: 577072
Relations between seizures induced by repeated electroshock (ES) and structural changes in the hippocampus were investigated in Balb/C mice. Brain sections of the animals 2 or 7 days after the last ES were stained for Nissl or TUNEL (apoptotic nuclei). Direct measurement of caspase-3 activity (a key enzyme of apoptosis) in brain regions was performed immediately after the last ES. Statistically significant, albeit moderate cell loss was demonstrated in the CA1 field and dentate gyrus, but not in the CA3 field of the hippocampus. The number of neurons in these fields inversely correlated with seizure severity. No apoptotic nuclei could be revealed either in hippocampus or in other brain regions. Caspase-3 in the hippocampus decreased after ES. The data obtained support the results from other groups showing prominent functional changes in neurons induced by repeated ES and extend this concept directly testifying for a moderate (within 10%), albeit statistically significant neuronal death in selected hippocampal fields. The inverse correlation of cell number with severity of seizures suggest that these are seizures inducing neuronal death.