Muscarinic Enhancement of R-Type Calcium Currents in Hippocampal CA1 Pyramidal Neurons
| Autor: | J. B. Kuzmiski, Chao Tai, Brian A. MacVicar |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Patch-Clamp Techniques
Cholinergic Agents chemistry.chemical_element Stimulation Calcium Channels R-Type In Vitro Techniques Biology Calcium Hippocampal formation Hippocampus Rats Sprague-Dawley Calcium Channels T-Type Muscarine Muscarinic acetylcholine receptor Animals Theta Rhythm Protein Kinase C Protein kinase C Receptor Muscarinic M3 Pyramidal Cells General Neuroscience Receptor Muscarinic M1 Electric Conductivity Articles Rats Electrophysiology chemistry Biophysics Cholinergic Carbachol Signal transduction Neuroscience Intracellular Signal Transduction |
| Zdroj: | Journal of Neuroscience. 26:6249-6258 |
| ISSN: | 1529-2401 0270-6474 |
| DOI: | 10.1523/jneurosci.1009-06.2006 |
| Popis: | The “toxin-resistant” R-type Ca(2+) channels are expressed widely in the CNS and distributed mainly in apical dendrites and spines. They play important roles in regulating signal transduction and intrinsic properties of neurons, but the modulation of these channels in the mammalian CNS has not been studied. In this study we used whole-cell patch-clamp recordings and found that muscarinic activation enhances R-type, but does not affect T-type, Ca(2+) currents in hippocampal CA1 pyramidal neurons after N, P/Q, and L-type Ca(2+) currents selectively were blocked. M(1)/M(3) cholinergic receptors mediated the muscarinic stimulation of R-type Ca(2+) channels. The signaling pathway underlying the R-type enhancement was independent of intracellular [Ca(2+)] changes and required the activation of a Ca(2+)-independent PKC pathway. Furthermore, we found that the enhancement of R-type Ca(2+) currents resulted in the de novo appearance of Ca(2+) spikes and in remarkable changes in the firing pattern of R-type Ca(2+) spikes, which could fire repetitively in the theta frequency. Therefore, muscarinic enhancement of R-type Ca(2+) channels could play an important role in modifying the dendritic response to synaptic inputs and in the intrinsic resonance properties of neurons. |
| Databáze: | OpenAIRE |
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