caa a22 4500 606202757 CHVBK 20210128100954.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00429-014-0762-4 doi (NATIONALLICENCE)springer-10.1007/s00429-014-0762-4 Functional expression and axonal transport of α7 nAChRs by peptidergic nociceptors of rat dorsal root ganglion [Elektronische Daten] [Irina Shelukhina, Renate Paddenberg, Wolfgang Kummer, Victor Tsetlin] In recent pain studies on animal models, α7 nicotinic acetylcholine receptor (nAChR) agonists demonstrated analgesic, anti-hyperalgesic and anti-inflammatory effects, apparently acting through some peripheral receptors. Assuming possible involvement of α7 nAChRs on nociceptive sensory neurons, we investigated the morphological and neurochemical features of the α7 nAChR-expressing subpopulation of dorsal root ganglion (DRG) neurons and their ability to transport α7 nAChR axonally. In addition, α7 receptor activity and its putative role in pain signal neurotransmitter release were studied. Medium-sized α7 nAChR-expressing neurons prevailed, although the range covered all cell sizes. These cells accounted for one-fifth of total medium and large DRG neurons and <5% of small ones. 83.2% of α7 nAChR-expressing DRG neurons were peptidergic nociceptors (CGRP-immunopositive), one half of which had non-myelinated C-fibers and the other half had myelinated Aδ- and likely Aα/β-fibers, whereas 15.2% were non-peptidergic C-fiber nociceptors binding isolectin B4. All non-peptidergic and a third of peptidergic α7 nAChR-bearing nociceptors expressed TRPV1, a capsaicin-sensitive noxious stimulus transducer. Nerve crush experiments demonstrated that CGRPergic DRG nociceptors axonally transported α7 nAChRs both to the spinal cord and periphery. α7 nAChRs in DRG neurons were functional as their specific agonist PNU282987 evoked calcium rise enhanced by α7-selective positive allosteric modulator PNU120596. However, α7 nAChRs do not modulate neurotransmitter CGRP and glutamate release from DRG neurons since nicotinic ligands affected neither their basal nor provoked levels, showing the necessity of further studies to elucidate the true role of α7 nAChRs in those neurons. Springer-Verlag Berlin Heidelberg, 2014 Sensory ganglia nationallicence Nicotinic acetylcholine receptor nationallicence Nociception nationallicence Nociceptor nationallicence Calcitonin gene-related peptide nationallicence Shelukhina Irina Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya str., 16/10, 117997, Moscow, Russia aut Paddenberg Renate Institute for Anatomy and Cell Biology, Justus-Liebig-University, 35385, Giessen, Germany aut Kummer Wolfgang Institute for Anatomy and Cell Biology, Justus-Liebig-University, 35385, Giessen, Germany aut Tsetlin Victor Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya str., 16/10, 117997, Moscow, Russia aut Brain Structure and Function Springer Berlin Heidelberg 220/4(2015-07-01), 1885-1899 1863-2653 220:4<1885 2015 220 429 https://doi.org/10.1007/s00429-014-0762-4 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00429-014-0762-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shelukhina Irina Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya str., 16/10, 117997, Moscow, Russia aut NATIONALLICENCE 700 1- Paddenberg Renate Institute for Anatomy and Cell Biology, Justus-Liebig-University, 35385, Giessen, Germany aut NATIONALLICENCE 700 1- Kummer Wolfgang Institute for Anatomy and Cell Biology, Justus-Liebig-University, 35385, Giessen, Germany aut NATIONALLICENCE 700 1- Tsetlin Victor Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya str., 16/10, 117997, Moscow, Russia aut NATIONALLICENCE 773 0- Brain Structure and Function Springer Berlin Heidelberg 220/4(2015-07-01), 1885-1899 1863-2653 220:4<1885 2015 220 429