Effects of prenatal protein malnutrition on kindling-induced alterations in dentate granule cell excitability. II. Paired-pulse measures.

摘要: Abstract The effects of prenatal protein malnutrition on kindling-induced changes in inhibitory modulation dentate granule cell activity were examined by analysis extracellular field potentials recorded from the layer gyrus response to paired-pulse stimulation perforant pathway freely-moving rats. Since we have shown that kindling results enhanced synaptic transmission at level path/granule synapse (see preceding paper), sought determine if process might induce excitability which could be involved slower acquisition kindled state previously reported malnourished animals. Beginning 120–150 days age, cells path was interpulse intervals (IPIs) ranging 20–1000 ms. A index (PPI) constructed based mean percent change population spike amplitudes two responses resulting application pulse pair. PPI measures obtained during compared with individual prekindling excitatory/inhibitory activity. Significant inhibition second apparent all IPIs tested for both diet groups following first afterdischarge. This included significantly levels early (IPIs ≤ 40 ms) and late ≥ 300 phase, as well a complete disappearance facilitation phase > ms but 6% 25% group, while animals control group continued show same magnitude those stage 5 convulsion. Our indicate induces alterations systems modulating significant enhancement depression. These appear transitory more enduring nature group. We suggest this may directly related rate relative inability consistently attain observed Paralleling paper, dietary insult irreversible mature even after prolonged period rehabilitation.