Low-[Mg2+]-induced Ca2+ fluctuations in organotypic hippocampal slice cultures.
We show here by whole field monitoring of free intracellular Ca2+ ([Ca2+]i), locally recorded field potential (fp) and external [Ca2+], that low-[Mg2+] induces seizure like events (SLEs) accompanied by simultaneous fluctuations of [Ca2+]i and [Ca2+]e in cultured hippocampal slices. Within a SLE, complex [Ca2+]e fluctuations are seen throughout phases of Ca2+ depletion (tonic) and Ca2+ recovery (clonic) of the extracellular space. Information theory entropy-based analyses revealed strong asymmetric associations of [Ca2+]i and [Ca2+]e kinetics. By contrast, signal-associations between SLEs were found to be weak and of symmetric nature distinguishing seizure-like and interictal events by extensive coupling and decoupling of [Ca2+]i and [Ca2+]e fluctuations, respectively.
Department of Neurochemistry, Chemical Institute, Chemical Research Center, Hungarian Academy of Sciences, Budapest.
R
R
Kovács
N
N
Szilágyi
P
P
Barabás
U
U
Heinemann
J
J
Kardos
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology / Q000502:physiology*; D008275:Magnesium Deficiency; D009924:Organ Culture Techniques; D051381:Rats; D012640:Seizures / Q000503:physiopathology
D008274:Magnesium; D002118:Calcium