Introduction: Antibiotic supplements are regularly used in neuronal culture media to control contamination however, they can interfere with the neuronal excitability and affect electrophysiological properties. Therefore, in this study, the effect of penicillin/streptomycin supplements on the spontaneous electrophysiological activity of hippocampal pyramidal neurons was examined. Methods: Electr...

Colchicine, a potent neurotoxin derived from plants, has been recently introduced as a degenerative toxin of small pyramidal cells in the cortical area 1 of the hippocampus (CA1). In this study, the effect of the alkaloid in CA1 on the behaviors in the conditioning task was measured. Injections of colchicine (1,5 μg/rat, intra-CA1) was performed in the male Wistar rats, while the animals were s...

Our previous studies of calcium (Ca(2+)) currents in cortical pyramidal cells revealed that the percentage contribution of each Ca(2+) current type to the whole cell Ca(2+) current varies from cell to cell. The extent to which these currents are modulated by neurotransmitters is also variable. This study was directed at testing the hypothesis that a major source of this variability is recording...

Layer 2/3 (L2/3) pyramidal cells receive excitatory afferent input both from neighbouring pyramidal cells and from cortical and subcortical regions. The efficacy of these excitatory synaptic inputs is modulated by spike timing-dependent plasticity (STDP). Here we report that synaptic connections between L2/3 pyramidal cell pairs are located proximal to the soma, at sites overlapping those of ex...

The brain is composed of diverse types of neurons that fulfill distinct roles in neuronal circuits, as manifested by the hippocampus, where pyramidal neurons and granule cells constitute functionally distinct domains: cornu ammonis (CA) and dentate gyrus (DG), respectively. Little is known about how these two types of neuron differentiate during hippocampal development, although a set of transc...

Among the electrophysiological properties differentiating stratum oriens horizontal interneurons from pyramidal neurons of the CA1 hippocampal subfield are the more depolarized resting potential and the higher input resistance; additionally, these interneurons are also less sensitive to ischemic damage than pyramidal cells. A differential expression of pH-sensitive leakage potassium channels (T...

Carbachol (> 20 microM) and kainate (100 nM) induce, in the in vitro CA3 region, synchronized neuronal population oscillations at approximately 40 Hz having distinctive features: (i) the oscillations persist for hours; (ii) interneurons in kainate fire at 5-20 Hz and their firing is tightly locked to field potential maxima (recorded in s. radiatum); (iii) in contrast, pyramidal cells, in both c...

Here we address how dynamics of glutamatergic and GABAergic synaptic input to CA3 pyramidal cells contribute to spontaneous emergence and evolution of recurrent seizure-like events (SLEs) in juvenile (P10-13) rat hippocampal slices bathed in low-[Mg(2+)] artificial cerebrospinal fluid. In field potential recordings from the CA3 pyramidal layer, a short epoch of high-frequency oscillation (HFO; ...

Experimental mouse chimeras have proven useful in analyzing the cell lineages of various tissues. Here we use experimental mouse chimeras to study cell lineage of the hippocampus. We examined clonal architecture and lineage relationships of the hippocampal pyramidal cells, dentate granule cells, and GABAergic interneurons. We quantitatively analyzed like-genotype cohorts of these neuronal popul...

Alzheimer’s disease (AD) is undoubtedly one of the serious and growing public health challenges in the world today. There is an unmet need for new and effective preventative and therapeutic treatment approaches for AD, particularly at early stages of the disease. However, the underlying mechanism against Aβ-induced electrophysiological alteration in cultured hippocampal pyramidal neurons  is st...