Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons
<p>Abstract</p> <p>Background</p> <p>Gain-of-function mutations of the nociceptive voltage-gated sodium channel Nav1.7 lead to inherited pain syndromes, such as paroxysmal extreme pain disorder (PEPD). One characteristic of these mutations is slowed fast-inactivation ki...
| Main Authors: | , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
SAGE Publishing
2012-09-01
|
| Series: | Molecular Pain |
| Subjects: | |
| Online Access: | http://www.molecularpain.com/content/8/1/69 |
| _version_ | 1811244859181236224 |
|---|---|
| author | Klinger Alexandra B Eberhardt Mirjam Link Andrea S Namer Barbara Kutsche Lisa K Schuy E Sittl Ruth Hoffmann Tali Alzheimer Christian Huth Tobias Carr Richard W Lampert Angelika |
| author_facet | Klinger Alexandra B Eberhardt Mirjam Link Andrea S Namer Barbara Kutsche Lisa K Schuy E Sittl Ruth Hoffmann Tali Alzheimer Christian Huth Tobias Carr Richard W Lampert Angelika |
| author_sort | Klinger Alexandra B |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>Gain-of-function mutations of the nociceptive voltage-gated sodium channel Nav1.7 lead to inherited pain syndromes, such as paroxysmal extreme pain disorder (PEPD). One characteristic of these mutations is slowed fast-inactivation kinetics, which may give rise to resurgent sodium currents. It is long known that toxins from <it>Anemonia sulcata</it>, such as ATX-II, slow fast inactivation and skin contact for example during diving leads to various symptoms such as pain and itch. Here, we investigated if ATX-II induces resurgent currents in sensory neurons of the dorsal root ganglion (DRGs) and how this may translate into human sensations.</p> <p>Results</p> <p>In large A-fiber related DRGs ATX-II (5 nM) enhances persistent and resurgent sodium currents, but failed to do so in small C-fiber linked DRGs when investigated using the whole-cell patch-clamp technique. Resurgent currents are thought to depend on the presence of the sodium channel β4-subunit. Using RT-qPCR experiments, we show that small DRGs express significantly less β4 mRNA than large sensory neurons. With the β4-C-terminus peptide in the pipette solution, it was possible to evoke resurgent currents in small DRGs and in Nav1.7 or Nav1.6 expressing HEK293/N1E115 cells, which were enhanced by the presence of extracellular ATX-II. When injected into the skin of healthy volunteers, ATX-II induces painful and itch-like sensations which were abolished by mechanical nerve block. Increase in superficial blood flow of the skin, measured by Laser doppler imaging is limited to the injection site, so no axon reflex erythema as a correlate for C-fiber activation was detected.</p> <p>Conclusion</p> <p>ATX-II enhances persistent and resurgent sodium currents in large diameter DRGs, whereas small DRGs depend on the addition of β4-peptide to the pipette recording solution for ATX-II to affect resurgent currents. Mechanical A-fiber blockade abolishes all ATX-II effects in human skin (e.g. painful and itch-like paraesthesias), suggesting that it mediates its effects mainly via activation of A-fibers.</p> |
| first_indexed | 2024-04-12T14:32:08Z |
| format | Article |
| id | doaj.art-132c2cd724904d65aa5f279e983eb84b |
| institution | Directory Open Access Journal |
| issn | 1744-8069 |
| language | English |
| last_indexed | 2024-04-12T14:32:08Z |
| publishDate | 2012-09-01 |
| publisher | SAGE Publishing |
| record_format | Article |
| series | Molecular Pain |
| spelling | doaj.art-132c2cd724904d65aa5f279e983eb84b2022-12-22T03:29:13ZengSAGE PublishingMolecular Pain1744-80692012-09-01816910.1186/1744-8069-8-69Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neuronsKlinger Alexandra BEberhardt MirjamLink Andrea SNamer BarbaraKutsche Lisa KSchuy ESittl RuthHoffmann TaliAlzheimer ChristianHuth TobiasCarr Richard WLampert Angelika<p>Abstract</p> <p>Background</p> <p>Gain-of-function mutations of the nociceptive voltage-gated sodium channel Nav1.7 lead to inherited pain syndromes, such as paroxysmal extreme pain disorder (PEPD). One characteristic of these mutations is slowed fast-inactivation kinetics, which may give rise to resurgent sodium currents. It is long known that toxins from <it>Anemonia sulcata</it>, such as ATX-II, slow fast inactivation and skin contact for example during diving leads to various symptoms such as pain and itch. Here, we investigated if ATX-II induces resurgent currents in sensory neurons of the dorsal root ganglion (DRGs) and how this may translate into human sensations.</p> <p>Results</p> <p>In large A-fiber related DRGs ATX-II (5 nM) enhances persistent and resurgent sodium currents, but failed to do so in small C-fiber linked DRGs when investigated using the whole-cell patch-clamp technique. Resurgent currents are thought to depend on the presence of the sodium channel β4-subunit. Using RT-qPCR experiments, we show that small DRGs express significantly less β4 mRNA than large sensory neurons. With the β4-C-terminus peptide in the pipette solution, it was possible to evoke resurgent currents in small DRGs and in Nav1.7 or Nav1.6 expressing HEK293/N1E115 cells, which were enhanced by the presence of extracellular ATX-II. When injected into the skin of healthy volunteers, ATX-II induces painful and itch-like sensations which were abolished by mechanical nerve block. Increase in superficial blood flow of the skin, measured by Laser doppler imaging is limited to the injection site, so no axon reflex erythema as a correlate for C-fiber activation was detected.</p> <p>Conclusion</p> <p>ATX-II enhances persistent and resurgent sodium currents in large diameter DRGs, whereas small DRGs depend on the addition of β4-peptide to the pipette recording solution for ATX-II to affect resurgent currents. Mechanical A-fiber blockade abolishes all ATX-II effects in human skin (e.g. painful and itch-like paraesthesias), suggesting that it mediates its effects mainly via activation of A-fibers.</p>http://www.molecularpain.com/content/8/1/69Patch-clampPsychophysicsDifferential nerve blockSensory neuronsItchSodium channelsRT-qPCR<it>SCN4b</it> |
| spellingShingle | Klinger Alexandra B Eberhardt Mirjam Link Andrea S Namer Barbara Kutsche Lisa K Schuy E Sittl Ruth Hoffmann Tali Alzheimer Christian Huth Tobias Carr Richard W Lampert Angelika Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons Molecular Pain Patch-clamp Psychophysics Differential nerve block Sensory neurons Itch Sodium channels RT-qPCR <it>SCN4b</it> |
| title | Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons |
| title_full | Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons |
| title_fullStr | Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons |
| title_full_unstemmed | Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons |
| title_short | Sea-anemone toxin ATX-II elicits A-fiber-dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons |
| title_sort | sea anemone toxin atx ii elicits a fiber dependent pain and enhances resurgent and persistent sodium currents in large sensory neurons |
| topic | Patch-clamp Psychophysics Differential nerve block Sensory neurons Itch Sodium channels RT-qPCR <it>SCN4b</it> |
| url | http://www.molecularpain.com/content/8/1/69 |
| work_keys_str_mv | AT klingeralexandrab seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT eberhardtmirjam seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT linkandreas seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT namerbarbara seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT kutschelisak seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT schuye seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT sittlruth seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT hoffmanntali seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT alzheimerchristian seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT huthtobias seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT carrrichardw seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons AT lampertangelika seaanemonetoxinatxiielicitsafiberdependentpainandenhancesresurgentandpersistentsodiumcurrentsinlargesensoryneurons |