Abstract
Hyppocampal epilepsy is a recently defined syndrome occurring in 65% of all temporal lobe epilepsies as defined by: 1) electrographic (EEG) onset in the hippocampus (HC) prior to EEG seizures elsewhere, 2) post-resection hippocampal sclerosis and mossy fiber synaptic reorganizations and 3) relief of typical complex partial seizures after surgical resection of the hyppocampus. We used intrahippocampal kainic acid injections V2 in rats at different developmental ages (postnatal 7 through adult) to develop long term spontaneous HC EEG spikes, EEG seizures, and behavioral seizures. Split-screen video/EEG monitoring demonstrated that this intrahippocampal kainic acid model produced progressive development of: 1) ipsilateral interictal spikes, 2) later polyspike complexes, 3) bilaterally-asynchronous EEG spiking, 4) unilateral HC EEG seizure onsets with occasional secondarily generalized spread to apposite HC and motor cortex to elicit complex partial seizures, and 5) in all seizing rats there was mossy fiber synaptic reorganization, even when injected at age 7 days. These results indicate that the intrahippocampal kainic acid injection model is similar to human hippocampal epilepsy.
Sommario
L'epilessia ippocampale è una sindrome recentemente definita che si riscontra nel 65% di tutte le epilessie del lobo temporale ed è caratterizzata da: 1) esordio elettrografico (EEG) nell'ippocampo (HC) precedente l'attività EEG critica nelle altre strutture; 2) riscontro di sclerosi ippocampale e di riorganizzazione sinaptica delle fibre muscoidi nel tessuto asportato chirurgicamente; 3) regressione delle tipiche crisi parziali complesse in seguito a resezione chirurgica. Noi abbiamo iniezioni di acido cainico in ratti di diversa età postnatale (da P7 all'età adulta) per ottenere punte EEG persistenti in HC, attività EEG critica e crisi comportamentali. Il monitoraggio video-EEG ha dimostrato che in questo modello ottenuto con iniezione intraippocampale di acido cainico si osserva il progressivo sviluppo di: 1) punte EEG interittali ipsilaterali; 2) in uno stadio successivo complessi di polipunta; 3) scariche di punte EEG bilaterali asincrone; 4) crisi parziali complesse associate a scariche EEG che iniziano nell'HC di un lato e si propagano occasionalmente all'HC del lobo opposto e alla corteccia motoria; 5) riorganizzazione sinaptica delle fibre muscoidi in tutti i ratti con crisi anche se iniettati precocemente (P7).
Questi risultati indicano che il modello ottenuto con iniezione intraippocampale di acido cainico è assimilabile all'epilessia ippocampale umana.
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References
Albala B.J., Moshé S.L., Okada R.:Kainic acidinduced seizures: a developmental study. Dev. Brain Res., 13: 139–148, 1984.
Babb T.L., Kupfer W.R., Pretorius J.K., Crandall P.H., Levesque M.F.:Synaptic reorganization by mossy fibers in human epileptic fascia dentata. Neuroscience, 42: 351–362, 1991.
Babb T.L., Pretorius J.K., Kupfer W.R., Crandall P.H.:Glutamate decarboxylase immunoreactive neurons are preserved in human epileptic hippocampus. J. Neurosci. 9:2562–2574, 1989.
Babb T.L., Pretorius J.K., Mello L.E., Mathern G.W., Levesque M.F.:Synaptic reorganizations in epileptic human and rat kainate hippocampus may contribute to feedback and feedforward excitation. In: Molecular Neurobiology of Epilepsy (Epilepsy Res. Suppl. 9), Engel J Jr., Wasterlain C., Cavalheiro E.A., Heinemann U., and Avanzini G. eds. Elsevier Science Publishers B.V., pp. 193–203, 1992.
Berger M.L., Lefauconnier J.M., Tremblay E., Ben-Ari Y.:Limbic seizures induced by systemically applied kainic acid: how much kainic acid reaches the brain? In: Schwarcz E. and Ben-Ari Y. (eds.) Excitatory Amino Acids and Epilepsy. New York: Plenum, pp. 199–209, 1986.
Cavalheiro E.A., Riche D.A., Le Gal La Salle G.:Long-term effects of intrahippocampal kainic acid injection in rats: a method for inducing spontaneous recurrent seizures. Electroencephalorg. Clin. Neurophysiol., 53: 581–589, 1982.
Cronin J., Dudek F.E.:Chronic seizures and collateral sprouting of dentate mossy fibers after kainic acid treatment in rats. Brain Res. 474: 181–184, 1988.
Davenport C.J., Brown W.J., Babb T.L.:Sprouting of GABAergic and mossy fiber axons in dentate gyrus following intrahippocampal kainate in the rat. Exp. Neurol., 109: 180:190, 1990.
Davenport C.J., Brown W.J., Babb T.L.:GABAergic neurons are spared after intrahippocampal kainate in the rat. Epilepsy Res., 5: 28–42, 1990.
Engel Jr.J.:Surgical treatment of the epilepsies. New York: Raven Press, 1987.
Engel Jr.J.:Surgical treatment of the epilepsies, second edition. New York: Raven Press, 1993.
Golden G.T., Smith G.G., Ferraro T.N., Reyes P.F., Kulp J.K., Fariello R.G.:Strain differences in convulsive response to the excitotoxin kainic acid. Neuro Report., 2: 141–144, 1991.
Holmes G., Thompson J.L.:Effects of kainic acid on seizure susceptibility in the developing brain. Dev. Brain Res., 39: 51–59, 1988.
Lüders H.O.:Epilepsy surgery. New York: Raven Press, 1992.
Mathern G. W., Kupfer W.R., Pretorius J.K., Babb T.L., Levesque M.F.:Onset and patterns of hippocampal sprouting in the rat kainate seizure model: evidence for progressive cell loss and neo-innervation in regio inferior and superior. Dendron, 1: 69–84, 1992.
Mathern G.W., Cifuentes F., Leite J.P., Pretorius J.K., Babb T.L.:Hippocampal EEG excitability and chronic spontaneous seizures are associated with aberrant synaptic reorganization in the rat intrahippocampal kainate model. Electroencephalogr: Clin. Neurophysiol, 87: 326–339, 1993.
Mathern G.W., Babb T.L., Vickrey B.G., Melendez M., Pretorius J.K.:Traumatic compared to non-traumatic clinical pathologic association in temporal lobe epilepsy. Epilepsy Res., 19:129–139, 1994.
Nadler J.V.:Seizures and neuronal cell death in the hippocampus. In: Köhler C., and Chan-Palay V. (eds.) The hippocampus-new vistas. New York: Alan R. Liss, Inc, pp. 463–481, 1989.
Schwob J.E., Fuller T., Price J.L., Olney J.W.:Widespread patterns of neuronal damage following systemic or intracerebral injection of kainic acid: a histological study. Neuroscience, 5: 991–1014, 1980.
Sherwood N.M., Timiras P.S.:A stereotaxic atlas of the developing rat brain. U.C. Press, Los Angeles, 1970.
Sperk G.:Kainic acid seizures in the rat. Prog. Neurobiol., 42: 1–31, 1994.
Tauck D., Nadler J.V.:Evidence of functional mossy fiber sprouting in hippocampal formation of kainic acid-treated rats. J. Neurosci., 5: 1016–1022, 1985.
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Supported by NIH Grants NS 02808, NS 31655 (T.L.B.); K08 NS 1603 (G.W.M.); and Fogarty Fellowship TWO 4959 (J.P.L.).
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Babb, T.L., Pereira-Leite, J., Mathern, G.W. et al. Kainic acid induced hippocampal seizures in rats: comparisons of acute and chronic seizures using intrahippocampal versus systemic injections. Ital J Neuro Sci 16, 39–44 (1995). https://doi.org/10.1007/BF02229073
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DOI: https://doi.org/10.1007/BF02229073