Kindling-induced potentiation of excitatory and inhibitory inputs to hippocampal dentate granule cells. II. Effects of the NMDA antagonist MK-801.
The effect of the non-competitive N-methyl-D-aspartate antagonist MK-801 on the early development of kindling-induced potentiation was examined in the rabbit hippocampal dentate gyrus. MK-801 (0.5 mg/kg) was administered 2 h before each daily kindling stimulation was applied to the perforant path. This treatment continued for the first 10 days of kindling. MK-801 depressed the growth of the afterdischarge duration and suppressed development of behavioral seizures. MK-801 did not block kindling-induced potentiation of either the perforant path-dentate granule cell population spike or excitatory postsynaptic potential. Random impulse train stimulation and non-linear systems analytic techniques were used to examine kindling-induced potentiation of presumed GABAergic recurrent inhibitory circuits. Both the magnitude and duration of kindling-induced response inhibition, to the second of each pair of impulses within the train, were reduced in rabbits pretreated with MK-801. These results suggest that MK-801 differentially affects kindling-induced potentiation of excitatory and inhibitory circuits within the rabbit hippocampal dentate gyrus.
Robinson
G B
GB
Department of Psychology, University of New Brunswick, Fredericton, Canada.
D000704:Analysis of Variance; D000818:Animals; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D007696:Kindling, Neurologic; D008297:Male; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors; D011817:Rabbits; D012640:Seizures / Q000503:physiopathology
D016202:N-Methylaspartate; D016291:Dizocilpine Maleate