Experimental Brain Research

, 72:45

Membrane properties, response to amines and to tetanic stimulation of hippocampal neurons in the genetically epileptic mutant mouse tottering

  • G. Kostopoulos
  • C. Psarropoulou
  • H. L. Haas
Article

DOI: 10.1007/BF00248499

Cite this article as:
Kostopoulos, G., Psarropoulou, C. & Haas, H.L. Exp Brain Res (1988) 72: 45. doi:10.1007/BF00248499

Summary

The petit-mal seizures of the “tottering” mutant mouse (tg) have been attributed to an exaggerated noradrenergic projection from locus coeruleus to the telencephalon (Noebels 1984). In order to investigate the possible epileptogenic mechanisms involved, we have compared hippocampal slices from epileptic (tg/tg) and phenotypically healthy (tg/+) mice. Resting potentials, action potentials and afterpotentials, membrane impedances and time constants were not significantly different in 11 neurons from each group. Bath application of noradrenaline, isoproterenol and histamine or a transient exposure to Mg++-free medium caused a long lasting increase in extracellularly recorded population spikes induced in CA1 by electrical stimulation of stratum radiatum. Isoproterenol blocked the calcium dependent afterhyperpolarization and accommodation of firing. Tetanization of afferent fibres evoked post-tetanic potentiation and long-term potentiation. All these results are qualitatively similar to those previously described in rats and guinea pigs and have revealed no significant difference between tg/tg and tg/+ mice.

Key words

Epilepsy Tottering mutant Hippocampal slices Membrane excitability Noradrenaline Long-term potentiation 

Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • G. Kostopoulos
    • 1
    • 2
  • C. Psarropoulou
    • 1
    • 2
  • H. L. Haas
    • 1
    • 2
  1. 1.Department of NeurosurgeryUniversity of ZürichZürichSwitzerland
  2. 2.Department of PhysiologyUniversity of Patras Medical SchoolPatrasGreece
  3. 3.Department of PhysiologyUniversity of MainzMainzGermany