Increased inhibitory input to CA1 pyramidal cells alters hippocampal gamma frequency oscillations in the MK-801 model of acute psychosis.
Colin Kehrer, Tamar Dugladze, Nino Maziashvili, Anna Wójtowicz, Dietmar Schmitz, Uwe Heinemann, Tengis Gloveli
Neurobiology of disease March 1, 2007 DOI: 10.1016/j.nbd.2006.10.015 via PubMed
Summary
AI-generated from the abstractExposure to the compound MK-801, which induces psychosis-like symptoms similar to those in acute schizophrenia, alters brain activity in an animal model. Gamma frequency oscillations in the hippocampus, evoked by kainate, were more powerful in animals that had received MK-801 than in controls. The resting membrane potential of pyramidal cells was more depolarized after MK-801, while other membrane properties remained unchanged. The authors suggest that changes in sodium-potassium pump activity and increased phasic inhibition may underlie these effects.
Study at a glance
| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Animals (rats or mice, not specified) |
| Intervention | MK-801 |
| Key finding | Gamma frequency oscillations were more powerful and resting membrane potentials were more depolarized in pyramidal cells from animals exposed to MK-801 compared to controls. |
Abstract
The phencyclidine compound MK-801 can induce psychosis with symptoms which closely resemble those observed in an acute schizophrenic episode. Here we used an in vitro model of psychosis after systemic administration of MK-801. We found that kainate-induced gamma frequency field oscillations in animals previously exposed to MK-801 have significantly higher power than in control animals. The intrinsic membrane properties of pyramidal cells, such as membrane input resistance and time constant, were not found to be different. In contrast, the MK-801 cells exhibited significantly more depolarized resting membrane potentials than control cells. We propose cellular alterations in Na+-K+-pump activity and increases in phasic inhibition in MK-801 cells to be the respective underlying mechanisms responsible for the more depolarized resting membrane potentials and the increased power of gamma frequency oscillations observed in MK-801 pretreated animals.