MEASUREMENT OF NMDA RECEPTOR PROTEIN SUBUNITS IN DISCRETE HIPPOCAMPALREGIONS OF KINDLED ANIMALS

Kindling refers to a phenomenon in which repeated application of initi ally subconvulsive electrical stimulations produces limbic and clonic motor seizures ol progressively increasing severity. Once established, the increased excitability is lifelong. A diversity of studies demons trate that kindling results in lone lasting (28 days) alterations of t he functional and pharmacologic properties of NMDA receptors, indicati ng that kindling may cause changes intrinsic to the NMDA receptor itse lf. Our previous studies disclosed no differences in NMDA receptor sub unit gene or splice isoform mRNA expression between control and kindle d animals 28 days after the last kindled seizure. Here, we extend thos e earlier studies by measuring levels of subunit protein for NMDAR1, N R2A, and NR2B in the hippocampus of control and kindled animals, 28 da ys after the last kindled seizure. We report that kindling does not ef fect long-lasting changes in the levels of NMDA receptor subunit prote in. Together these findings support the idea that alterations in NMDA receptor protein expression do not contribute to the novel properties of NMDA receptors induced by kindling. (C) 1998 Elsevier Science B.V. All rights reserved.