Nav1.6 but not KCa3.1 channels contribute to heterogeneity in coding abilities and dynamics of action potentials in the L5 neocortical pyramidal neurons.

Electrophysiological and genetic studies reveal two major subclasses of layer 5 (L5) neocortical pyramidal neurons that differ in electrical parameters and afterhyperpolarization. KCa3.1 channels are identified as contributors to slow afterhyperpolarization (sAHP), and they are expressed by one subclass of L5 neurons.

Ca-activated KCa3.1 potassium channels contribute to the slow afterhyperpolarization in L5 neocortical pyramidal neurons.

Layer 5 neocortical pyramidal neurons are known to display slow Ca-dependent afterhyperpolarization (sAHP) after bursts of spikes, which is similar to the sAHP in CA1 hippocampal cells. However, the mechanisms of sAHP in the neocortex remain poorly understood. Here, we identified the Ca-gated potassium KCa3.

Immediate-Early Genes Detection in the CNS of Terrestrial Snail.

In the present work, using in situ hybridization, we studied the expression patterns of three molluscan homologs of vertebrate immediate-early genes C/EBP, c-Fos, and c-Jun in the central nervous system (CNS) of terrestrial gastropod snail Helix. The molluscan C/EBP gene was described in literature, while c-Fos and c-Jun were studied in terrestrial snails for the first time. Localization of the expression was traced in normal conditions, and in preparations physiologically activated using stimulation of suboesophageal ganglia nerves.

Identification of Immediate Early Genes in the Nervous System of Snail .

Immediate early genes (IEGs) are useful markers of neuronal activation and essential components of neuronal response. While studies of gastropods have provided many insights into the basic learning and memory mechanisms, the genome-wide assessment of IEGs has been mainly restricted to vertebrates. In this study, we identified IEGs in the terrestrial snail In the absence of the genome, we conducted transcriptome assembly using reads with short and intermediate lengths cumulatively covering more than 98 billion nucleotides.

A BK channel-mediated feedback pathway links single-synapse activity with action potential sharpening in repetitive firing.

Action potential shape is a major determinant of synaptic transmission, and mechanisms of spike tuning are therefore of key functional significance. We demonstrate that synaptic activity itself modulates future spikes in the same neuron via a rapid feedback pathway. Using Ca imaging and targeted uncaging approaches in layer 5 neocortical pyramidal neurons, we show that the single spike-evoked Ca rise occurring in one proximal bouton or first node of Ranvier drives a significant sharpening of subsequent action potentials recorded at the soma.