Gean P W, Shinnick-Gallagher P
Department of Pharmacology and Toxicology, University of Texas, Medical Branch, Galveston 77550.
Exp Neurol. 1988 Aug;101(2):248-55. doi: 10.1016/0014-4886(88)90008-8.
The effect of Mg2+-free medium on neuronal activity in the basolateral nucleus of the rat amygdala slice was studied using intracellular recording techniques. Removal of Mg2+ from perfusate resulted in the development of three types of spontaneous activity, EPSP-like, ictal-like, and interictal-like events. The ictal-like events consisted of a long-duration depolarizing potential with several recurrent interictal bursts riding on it. The tonic and clonic firing phases seen in ictal-like events closely resembled the tonic and clonic phases of seizures which may provide a new model for studying the mechanisms underlying the generation of ictal seizures. The duration of interictal-like events induced in Mg2+-free solution is 10- to 30-fold longer than that produced by a convulsant. Two factors, a small or absent epileptiform afterhyperpolarization and a high density of NMDA receptor binding sites within the basolateral amygdala nucleus, may account for this difference.
