0000000000614071
AUTHOR
Jochen Moser
Dopaminergic modulation of low-Mg2+-induced epileptiform activity in the intact hippocampus of the newborn mouse in vitro
To investigate whether epileptiform activity in the immature brain is modulated by dopamine, we examined the effects of dopaminergic agonists and antagonists in an intact in vitro preparation of the isolated corticohippocampal formation of immature (postnatal days 3 and 4) C57/Bl6 mice using field potential recordings from CA3. Epileptiform discharges were induced by a reduction of the extracellular Mg(2+) concentration to 0.2 mM. These experiments revealed that low concentrations of dopamine ( 3 μM dopamine enhanced epileptiform activity. The D1-agonist SKF38393 (10 μM) had a strong proconvulsive effect, and the D2-like agonist quinpirole (10 μM) mediated a weak anticonvulsive effect. The …
Early developmental alterations of low-Mg2+ -induced epileptiform activity in the intact corticohippocampal formation of the newborn mouse in vitro.
Abstract The generation, propagation and pharmacological properties of low-Mg 2+ -induced epileptiform activity were examined in the intact corticohippocampal formation (CHF) of the newborn (P0–4) mouse in vitro. Multi-site field potential recordings in dentate gyrus (DG), CA3, CA1, entorhinal cortex (EC) and temporal cortex (TC) revealed in 0.2 mM Mg 2+ -containing ACSF a stable pattern of spontaneous epileptiform activity consisting of recurrent ictal-like events (ILEs) and interictal events (IEs). Although this activity could be consistently observed as early as P0, ILEs were smaller in amplitude, less frequent and showed a slower onset in P0–2 as compared to P3–4 animals. In all age gro…