Ca2+ waves in keratinocytes are transmitted to sensory neurons: the involvement of extracellular ATP and P2Y2 receptor activation

ATP acts as an intercellular messenger in a variety of cells. In the present study, we have characterized the propagation of Ca2+ waves mediated by extracellular ATP in cultured NHEKs (normal human epidermal keratinocytes) that were co-cultured with mouse DRG (dorsal root ganglion) neurons. Pharmacological characterization showed that NHEKs express functional metabotropic P2Y2 receptors. When a cell was gently stimulated with a glass pipette, an increase in [Ca2+]i (intracellular Ca2+ concentration) was observed, followed by the induction of propagating Ca2+ waves in neighbouring cells in an extracellular ATP-dependent manner. Using an ATP-imaging technique, the release and diffusion of ATP in NHEKs were confirmed. DRG neurons are known to terminate in the basal layer of keratinocytes. In a co-culture of NHEKs and DRG neurons, mechanical-stimulation-evoked Ca2+ waves in NHEKs caused an increase in [Ca2+]i in the adjacent DRG neurons, which was also dependent on extracellular ATP and the activation of P2Y2 receptors. Taken together, extracellular ATP is a dominant messenger that forms intercellular Ca2+ waves in NHEKs. In addition, Ca2+ waves in NHEKs could cause an increase in [Ca2+]i in DRG neurons, suggesting a dynamic cross-talk between skin and sensory neurons mediated by extracellular ATP.

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ASIC3 and ASIC1 Mediate FMRFamide-Related Peptide Enhancement of H+-Gated Currents in Cultured Dorsal Root Ganglion Neurons

Journal of Neurophysiology ◽

10.1152/jn.00707.2002 ◽

2003 ◽

Vol 89 (5) ◽

pp. 2459-2465 ◽

Cited By ~ 61

Author(s):

Jinghui Xie ◽

Margaret P. Price ◽

John A. Wemmie ◽

Candice C. Askwith ◽

Michael J. Welsh

Keyword(s):

Sensory Neurons ◽

Dorsal Root ◽

Dorsal Root Ganglion Neurons ◽

Cation Channels ◽

Dependent Manner ◽

Wild Type ◽

Drg Neurons ◽

Acid Sensing Ion Channels ◽

Ganglion Neurons ◽

Dose Dependent

The acid-sensing ion channels (ASICs) form cation channels that are transiently activated by extracellular protons. They are expressed in dorsal root ganglia (DRG) neurons and in the periphery where they play a function in nociception and mechanosensation. Previous studies showed that FMRFamide and related peptides potentiate H+-gated currents. To better understand this potentiation, we examined the effect of FMRFamide-related peptides on DRG neurons from wild-type mice and animals missing individual ASIC subunits. We found that FMRFamide and FRRFamide potentiated H+-gated currents of wild-type DRG in a dose-dependent manner. They increased current amplitude and slowed desensitization following a proton stimulus. Deletion of ASIC3 attenuated the response to FMRFamide-related peptides, whereas the loss of ASIC1 increased the response. The loss of ASIC2 had no effect on FMRFamide-dependent enhancement of H+-gated currents. These data suggest that FMRFamide-related peptides modulate DRG H+-gated currents through an effect on both ASIC1 and ASIC3 and that ASIC3 plays the major role. The recent discovery of RFamide-related peptides (RFRP) in mammals suggested that they might also modulate H+-gated current. We found that RFRP-1 slowed desensitization of H+-gated DRG currents, whereas RFRP-2 increased the peak amplitude. COS-7 cells heterologously expressing ASIC1 or ASIC3 showed similar effects. These results suggest that FMRFamide-related peptides, including the newly identified RFRPs, modulate H+-gated DRG currents through ASIC1 and ASIC3. The presence of several ASIC subunits, the diversity of FMRFamide-related peptides, and the distinct effects on H+-gated currents suggest the possibility of substantial complexity in modulation of current in DRG sensory neurons.

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Interaction of opioids and membrane potential to modulate Ca2+ channels in rat dorsal root ganglion neurons

Journal of Neurophysiology ◽

10.1152/jn.1995.73.5.1793 ◽

1995 ◽

Vol 73 (5) ◽

pp. 1793-1798 ◽

Cited By ~ 22

Author(s):

M. D. Womack ◽

E. W. McCleskey

Keyword(s):

Dorsal Root Ganglion ◽

Sensory Neurons ◽

Action Potentials ◽

Dorsal Root ◽

Dorsal Root Ganglion Neurons ◽

High Threshold ◽

Partial Recovery ◽

Drg Neurons ◽

Ganglion Neurons ◽

Ca2 Channels

1. Using patch-clamp methods, we show that brief prepulses to very positive voltages increase (facilitate) the amplitude of current through Ca2+ channels during a subsequent test pulse in some, but not all, dorsal root ganglion (DRG) sensory neurons. The amplitude of this facilitated current generally increases when the Ca2+ channels are inhibited by activation of the mu-opioid receptor. 2. The facilitated current is blocked by omega-conotoxin GVIA, activates in the range of high-threshold Ca2+ channels, and inactivates at relatively negative holding voltages. Thus facilitated current passes through N-type Ca2+ channels, the same channels that are inhibited by opioids and control neurotransmitter release in sensory neurons. 3. Although maximal facilitation occurs only at unphysiologically high membrane potentials (above +100 mV), some facilitation is seen after prepulses to voltages reached during action potentials. After return to the holding potential, facilitation persists for hundreds of milliseconds, considerably longer than in other neurons. Brief trains of pulses designed to mimic action potentials caused small facilitation (19% of maximal) in a fraction (8 of 24) of opioid-inhibited neurons. 4. We conclude that 1) prepulses to extremely positive voltages can cause partial recovery of Ca2+ channels inhibited by opioids; and 2) small, but detectable, facilitation is also seen after physiological stimulation in some DRG neurons. Facilitation, largely considered a biophysical epiphenomenon because of the extreme voltages used to induce it, appears to be physiologically relevant during opioid inhibition of Ca2+ channels in DRG neurons.

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Pain-enhancing mechanism through interaction between TRPV1 and anoctamin 1 in sensory neurons

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1421507112 ◽

2015 ◽

Vol 112 (16) ◽

pp. 5213-5218 ◽

Cited By ~ 73

Author(s):

Yasunori Takayama ◽

Daisuke Uta ◽

Hidemasa Furue ◽

Makoto Tominaga

Keyword(s):

Action Potential ◽

Sensory Neurons ◽

Transient Receptor Potential ◽

Receptor Potential ◽

Concomitant Administration ◽

Dorsal Root Ganglion Neurons ◽

Dependent Manner ◽

High Concentration ◽

Anoctamin 1 ◽

Ganglion Neurons

The capsaicin receptor transient receptor potential cation channel vanilloid 1 (TRPV1) is activated by various noxious stimuli, and the stimuli are converted into electrical signals in primary sensory neurons. It is believed that cation influx through TRPV1 causes depolarization, leading to the activation of voltage-gated sodium channels, followed by the generation of action potential. Here we report that the capsaicin-evoked action potential could be induced by two components: a cation influx-mediated depolarization caused by TRPV1 activation and a subsequent anion efflux-mediated depolarization via activation of anoctamin 1 (ANO1), a calcium-activated chloride channel, resulting from the entry of calcium through TRPV1. The interaction between TRPV1 and ANO1 is based on their physical binding. Capsaicin activated the chloride currents in an extracellular calcium-dependent manner in HEK293T cells expressing TRPV1 and ANO1. Similarly, in mouse dorsal root ganglion neurons, capsaicin-activated inward currents were inhibited significantly by a specific ANO1 antagonist, T16Ainh-A01 (A01), in the presence of a high concentration of EGTA but not in the presence of BAPTA [1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid]. The generation of a capsaicin-evoked action potential also was inhibited by A01. Furthermore, pain-related behaviors in mice treated with capsaicin, but not with αβ-methylene ATP, were reduced significantly by the concomitant administration of A01. These results indicate that TRPV1–ANO1 interaction is a significant pain-enhancing mechanism in the peripheral nervous system.

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Sa12b Peptide from Solitary Wasp Inhibits ASIC Currents in Rat Dorsal Root Ganglion Neurons

Toxins ◽

10.3390/toxins11100585 ◽

2019 ◽

Vol 11 (10) ◽

pp. 585 ◽

Cited By ~ 2

Author(s):

Hernández ◽

Konno ◽

Salceda ◽

Vega ◽

Zaharenko ◽

...

Keyword(s):

Dorsal Root Ganglion ◽

Dorsal Root ◽

Inhibitory Effect ◽

Dorsal Root Ganglion Neurons ◽

Dependent Manner ◽

Inhibitory Effects ◽

Drg Neurons ◽

Concentration Dependent Manner ◽

Acid Sensing Ion Channels ◽

Ganglion Neurons

In this work, we evaluate the effect of two peptides Sa12b (EDVDHVFLRF) and Sh5b (DVDHVFLRF-NH2) on Acid-Sensing Ion Channels (ASIC). These peptides were purified from the venom of solitary wasps Sphex argentatus argentatus and Isodontia harmandi, respectively. Voltage clamp recordings of ASIC currents were performed in whole cell configuration in primary culture of dorsal root ganglion (DRG) neurons from (P7-P10) CII Long-Evans rats. The peptides were applied by preincubation for 25 s (20 s in pH 7.4 solution and 5 s in pH 6.1 solution) or by co-application (5 s in pH 6.1 solution). Sa12b inhibits ASIC current with an IC50 of 81 nM, in a concentration-dependent manner when preincubation application was used. While Sh5b did not show consistent results having both excitatory and inhibitory effects on the maximum ASIC currents, its complex effect suggests that it presents a selective action on some ASIC subunits. Despite the similarity in their sequences, the action of these peptides differs significantly. Sa12b is the first discovered wasp peptide with a significant ASIC inhibitory effect.

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GDNF and NGF Reverse Changes in Repriming of TTX-Sensitive Na+ Currents Following Axotomy of Dorsal Root Ganglion Neurons

Journal of Neurophysiology ◽

10.1152/jn.2002.88.2.650 ◽

2002 ◽

Vol 88 (2) ◽

pp. 650-658 ◽

Cited By ~ 70

Author(s):

Andreas Leffler ◽

Theodore R. Cummins ◽

Sulayman D. Dib-Hajj ◽

William N. Hormuzdiar ◽

Joel A. Black ◽

...

Keyword(s):

Dorsal Root Ganglion ◽

Sodium Channel ◽

Sensory Neurons ◽

Dorsal Root ◽

Neuronal Excitability ◽

Dorsal Root Ganglion Neurons ◽

Current Profile ◽

Drg Neurons ◽

Α Subunit ◽

Ganglion Neurons

Uninjured C-type rat dorsal root ganglion (DRG) neurons predominantly express slowly inactivating TTX-resistant (TTX-R) and slowly repriming TTX-sensitive (TTX-S) Na+ currents. After peripheral axotomy, TTX-R current density is reduced and rapidly repriming TTX-S currents emerge and predominate. The change in TTX-S repriming kinetics is paralleled by an increase in the level of transcripts and protein for the Nav1.3 sodium channel α-subunit, which is known to exhibit rapid repriming. Changes in Na+current profile and kinetics in DRG neurons may substantially alter neuronal excitability and could contribute to some states of chronic pain associated with injury of sensory neurons. In the present study, we asked whether glial-derived neurotrophic factor (GDNF) and nerve growth factor (NGF), which have been shown to prevent some axotomy-induced changes such as the loss of TTX-R Na+ current expression in DRG neurons, can ameliorate the axotomy-induced change in TTX-S Na+ current repriming kinetics. We show that intrathecally administered GDNF and NGF, delivered individually, can partially reverse the effect of axotomy on the repriming kinetics of TTX-S Na+ currents. When GDNF and NGF were co-administered, the repriming kinetics were fully rescued. We observed parallel effects of GDNF and NGF on the Nav1.3 sodium channel transcript levels in axotomized DRG. Both GDNF and NGF were able to partially reverse the axotomy-induced increase in Nav1.3 mRNA, with GDNF plus NGF producing the largest effect. Our data indicate that both GDNF and NGF can partially reverse an important effect of axotomy on the electrogenic properties of sensory neurons and that their effect is additive.

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Annexin VI modulates Ca2+ and K+ conductances of spinal cord and dorsal root ganglion neurons

AJP Cell Physiology ◽

10.1152/ajpcell.1996.271.6.c2004 ◽

1996 ◽

Vol 271 (6) ◽

pp. C2004-C2015 ◽

Cited By ~ 29

Author(s):

J. M. Naciff ◽

M. M. Behbehani ◽

M. A. Kaetzel ◽

J. R. Dedman

Keyword(s):

Spinal Cord ◽

Plasma Membrane ◽

Sensory Neurons ◽

Dorsal Root ◽

Active Role ◽

Dorsal Root Ganglion Neurons ◽

Drg Neurons ◽

Preferential Localization ◽

Annexin Vi ◽

Ganglion Neurons

Annexin VI is a member of a Ca(2+)-dependent phospholipid-binding protein family that participates in the transduction of the intracellular Ca2+ signal. We have identified annexin VI as one of the major annexins expressed differentially by sensory neurons of dorsal root ganglia (DRG) and by neurons of spinal cord (SC) of the rat and the mouse. This annexin shows a preferential localization at the plasma membrane of the soma and cellular processes, particularly in motoneurons of the SC. This finding suggests an active role of annexin VI in the Ca(2+)-dependent regulation of plasma membrane functions. To test this possibility, the neuronal function of annexin VI was evaluated by whole cell electrophysiology of mouse embryo SC and DRG neurons. An antibody was developed that has the property of neutralizing annexin VI-phospholipid interactions. The intracellular perfusion of individual neurons in culture, either from SC or DRG, with monospecific affinity-purified anti-annexin VI antibodies resulted in an increase in the magnitude of the K+ current and in an increase in the Ca2+ current in sensory neurons. Our results suggest that the endogenous annexin VI regulates the Ca2+ conductance, which indirectly modifies Ca(2+)-dependent ionic conductances in SC and DRG neurons.

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Voltage-gated Na+ currents in human dorsal root ganglion neurons

eLife ◽

10.7554/elife.23235 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 30

Author(s):

Xiulin Zhang ◽

Birgit T Priest ◽

Inna Belfer ◽

Michael S Gold

Keyword(s):

Sensory Neurons ◽

Tissue Injury ◽

Dorsal Root Ganglion Neurons ◽

Pharmacological Properties ◽

Pain Mechanisms ◽

Voltage Gated ◽

Whole Cell Patch Clamp ◽

Na Currents ◽

Ganglion Neurons ◽

Peripheral Sensory

Available evidence indicates voltage-gated Na+ channels (VGSCs) in peripheral sensory neurons are essential for the pain and hypersensitivity associated with tissue injury. However, our understanding of the biophysical and pharmacological properties of the channels in sensory neurons is largely based on the study of heterologous systems or rodent tissue, despite evidence that both expression systems and species differences influence these properties. Therefore, we sought to determine the extent to which the biophysical and pharmacological properties of VGSCs were comparable in rat and human sensory neurons. Whole cell patch clamp techniques were used to study Na+ currents in acutely dissociated neurons from human and rat. Our results indicate that while the two major current types, generally referred to as tetrodotoxin (TTX)-sensitive and TTX-resistant were qualitatively similar in neurons from rats and humans, there were several differences that have important implications for drug development as well as our understanding of pain mechanisms.

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Sustained depolarization-induced propagation of [Ca2+]i oscillations in cultured DRG neurons: The involvement of extracellular ATP and P2Y receptor activation

Brain Research ◽

10.1016/j.brainres.2008.08.085 ◽

2008 ◽

Vol 1239 ◽

pp. 12-23 ◽

Cited By ~ 10

Author(s):

Yan Zeng ◽

Xiao-hua Lv ◽

Shao-qun Zeng ◽

Shun-lian Tian ◽

Man Li ◽

...

Keyword(s):

Receptor Activation ◽

Extracellular Atp ◽

P2y Receptor ◽

Drg Neurons

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On the inhibition of capsaicin response in dorsal root ganglion neurons by nobilamide B and analogues: a structure–activity relationship study

MedChemComm ◽

10.1039/c8md00304a ◽

2018 ◽

Vol 9 (10) ◽

pp. 1673-1678

Author(s):

Oliver John V. Belleza ◽

Jortan O. Tun ◽

Gisela P. Concepcion ◽

Aaron Joseph L. Villaraza

Keyword(s):

Dorsal Root Ganglion ◽

Primary Culture ◽

Dorsal Root ◽

Dorsal Root Ganglion Neurons ◽

Activity Relationship ◽

Drg Neurons ◽

Structure Activity ◽

Relationship Study ◽

Trpv1 Antagonist ◽

Ganglion Neurons

Nobilamide B, a TRPV1 antagonist, and a series of Ala-substituted analogues were synthesized and their neuroactivity was assessed in a primary culture of dorsal root ganglion (DRG) neurons.

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Delta/Notch signaling promotes formation of zebrafish neural crest by repressing Neurogenin 1 function

Development ◽

10.1242/dev.129.11.2639 ◽

2002 ◽

Vol 129 (11) ◽

pp. 2639-2648 ◽

Cited By ~ 4

Author(s):

Robert A. Cornell ◽

Judith S. Eisen

Keyword(s):

Dorsal Root Ganglion ◽

Neural Crest ◽

Notch Signaling ◽

Sensory Neurons ◽

Dorsal Root ◽

Cell Formation ◽

Dorsal Root Ganglion Neurons ◽

Primary Neurons ◽

Different Types ◽

Ganglion Neurons

In zebrafish, cells at the lateral edge of the neural plate become Rohon-Beard primary sensory neurons or neural crest. Delta/Notch signaling is required for neural crest formation. ngn1 is expressed in primary neurons; inhibiting Ngn1 activity prevents Rohon-Beard cell formation but not formation of other primary neurons. Reducing Ngn1 activity in embryos lacking Delta/Notch signaling restores neural crest formation, indicating Delta/Notch signaling inhibits neurogenesis without actively promoting neural crest. Ngn1 activity is also required for later development of dorsal root ganglion sensory neurons; however, Rohon-Beard neurons and dorsal root ganglion neurons are not necessarily derived from the same precursor cell. We propose that temporally distinct episodes of Ngn1 activity in the same precursor population specify these two different types of sensory neurons.

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