Ultrastructural Analysis of Rat Brain Tissue Following Systemic Kainate Administration
Morphological studies in models of experimental epilepsy have mainly focused on pathohistological changes of nerve cells (Schwob et al., 1980; Ben-Ari et al., 1981). Although it is evident, that neurons are the primary target in the action of excitotoxins, recent evidence suggests that besides direct neurotoxicity other pathogenetic mechanisms play an important role in the development of postepileptic brain damage. It is thus interesting to note, that irreversible neuropathological changes following kainic acid (KA) induced seizures not only involve nerve cells, but also glia, myelin sheaths and blood vessels (Sperk et al., 1983). In our present study we describe the sequence of morphological events in the limbic system of rats, systemically injected with KA. Our findings indicate that cytotoxic brain edema and subsequent focal ischemia plays a central role in the pathogenesis of irreversible seizure induced brain lesions.
KeywordsNerve Cell Brain Edema Kainic Acid Brain Damage Stratum Pyramidale
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- Atillo, A. Söderfeldt, B., Kalimo, H., Olsson, Y., and Siesjd, B.K., 1983, Pathogenesis of brain lesions caused by experimental epilepsy: light and electron microscopic changes in the rat hippocampus following bicuculline induced status epilepticus, Acta Neuropathol. 59: 11.Google Scholar
- Auer, R.N., Kalimo, H., Olsson, Y., and Siesjö, B.K., 1985, The temporal evolution of hypoglycemic brain damage. I. Light and electron microscopic findings in the rat cerebral cortex, Acta Neuropathol. 67: 13.Google Scholar
- Ben-Ari, Y. Tremblay, E., Riche, D., Ghilini, G., and Naquet, R., 1981, Electrographic, clinical and pathological alterations following systemic administration of kainic acid, bicuculline or pentetrazole: metabolic mapping using deoxyglucose method with special reference to pathology in epilepsy, Neuroscience 6:1361.Google Scholar
- Blennow, G., Brierley, J.B., Meldrum B.S, and Siesjö, B.K., 1978, Epileptic brain damage. The role of systemic factors that modify cerebral energy metabolism, Brain, 101: 687.Google Scholar
- Evans, M.C., Griffiths, T., and Meldrum, B.S., 1984, Kainic acid seizures and the reversibility of calcium loading in vulnerable neurones in the hippocampus, Neuropath. Appl. Neurobiol. 10:285.Google Scholar
- Lassmann, H., Petsche, U., Kitz, K., Baran, H., Sperk, G., Seitelberger, F., and Hornykiewicz, 0., 1984, The role of brain edema in epileptic brain damage induced by systemic kainic acid injection, Neuroscience 13: 691.Google Scholar
- Nitsch, C., and Klatzo, I., 1983, Regional patterns of blood brain barrier breakdown during epileptiform seizures induced by various convulsive agents, J. Neurol. Sei. 59:305.Google Scholar
- Reese, T.S., and Karnovski, M.J., 1967, Fine structural localization of a blood brain barrier to exogenous peroxidase, J. Cell. Biol. 34:207.Google Scholar
- Sperk, G., Lassmann, H., Baran, H., Kish, S.J., Seitelberger, F., and Hornykiewicz, 0., 1983, Kainic acid induced seizures: neurochemical and histopathological changes, Neuroscience 10: 1301.Google Scholar
- Spielmeyer, W., 1927, Die Pathogenese des epileptischen Krampfes. Histologischer Teil, Z. Ges. Neurol. Psychiat. 109:501.Google Scholar
- Wade, J. G., Amtorp, 0., and Sorensen, S.C., 1975, No flow state following cerebral ischemia. Role of increase in potassium concentration in brain interstitial fluid, Arch. Neurol. 32: 381.Google Scholar