ArticleKindling of the Dorsal and the Ventral Hippocampus: Effects on Learning Performance in Rats
Section snippets
Materials and Methods
For all procedures followed, ethical approval was sought prior to the experiments according to the requirements of the National Act on the Use of Experimental Animals (Germany).
Results
Repeated stimulation to both hippocampal structures resulted in constantly increasing seizure severity and seizure duration (Fig. 2). Regarding seizure severity, significant differences between the experimental groups were found (F(1, 50) = 18.02, p < 0.001). In the course of kindling development, seizure duration increased considerably (Fig. 2). However, there were no differences in seizure duration in rats after kindling of the ventral or the dorsal hippocampus (F(1, 50) = 0.68, p = 0.405).
Discussion
The results of this study indicate a functional differentiation of two regions in the hippocampal formation with regard to the induction of electrical kindling and subsequent learning impairments.
We found stimulation of the hippocampal formation resulted in kindling characterized by constantly increasing seizure severity (Fig. 2). Interestingly, there were striking differences in the initial phase of kindling. VH-kindled rats reached higher seizure scores, but following stimulation 10, the
Acknowledgements
We thank Mr. A. Toms (U.K.) for his help in improving the English.
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