title: Cholinergic modulation of synaptic properties of cortical layer VI input to posteromedial thalamic nucleus of the rat investigated in vitro.
abstract: The second order somatosensory thalamic nucleus (posteromedial nucleus, PoM) receives excitatory projection from layer VI of somatosensory cortex. While it is known that layer VI cortical input to first order, ventrobasal nucleus (VB) is modulated by cholinergic projections from the brainstem, no such data exists concerning the PoM nucleus. In order to study if layer VI corticothalamic transmission to PoM is also modulated we used patch-clamp recording in thalamocortical slices from the rat's brain. Excitatory postsynaptic potentials (EPSPs) were evoked in PoM cells by trains of 5 electrical pulses at 20 Hz frequency applied to corticothalamic fibers. After carbachol was applied to mimic activation of the cholinergic neuromodulatory system corticothalamic EPSP amplitudes were reduced, while facilitation of EPSP amplitudes was enhanced for each next pulse in the series. Such cholinergic control of layer VI corticothalamic synapses in PoM may be used as gain modulator for the transfer of the peripheral sensory information to the cortex.
authors: Department of Neurophysiology, Nencki Institute of Experimental Biology, Warsaw, Poland.
authors: Syune
authors: S
authors: Nersisyan
authors: Marek
authors: M
authors: Bekisz
authors: Ewa
authors: E
authors: Kublik
authors: Björn
authors: B
authors: Granseth
authors: Andrzej
authors: A
authors: Wróbel
mesh_terms: D000344:Afferent Pathways / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D001703:Biophysics; D002217:Carbachol / Q000494:pharmacology; D018678:Cholinergic Agents / Q000494:pharmacology*; D004558:Electric Stimulation; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D013569:Synapses / Q000187:drug effects / Q000502:physiology; D013787:Thalamic Nuclei / Q000166:cytology* / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology*
chemical_list: D018678:Cholinergic Agents; D002217:Carbachol