Preparing your results

Our searching services are busy right now. Your search will reload in five seconds.

X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

Mrgprd-expressing polymodal nociceptive neurons innervate most known classes of substantia gelatinosa neurons.

http://www.ncbi.nlm.nih.gov/pubmed/19846708

The Mas-related G-protein-coupled receptor D (Mrgprd) marks a distinct subset of sensory neurons that transmit polymodal nociceptive information from the skin epidermis to the substantia gelatinosa (SG, lamina II) of the spinal cord. Moreover, Mrgprd-expressing (Mrgprd(+)) neurons are required for the full expression of mechanical but not thermal nociception. While such anatomical and functional specificity suggests Mrgprd(+) neurons might synapse with specific postsynaptic targets in the SG, precisely how Mrgprd(+) neurons interface with spinal circuits is currently unknown. To study circuit connectivity, we genetically targeted the light-activated ion channel Channelrhodopsin-2-Venus (ChR2-Venus) to the Mrgprd locus. In these knock-in mice, ChR2-Venus was localized to nonpeptidergic Mrgprd(+) neurons and axons, while peptidergic CGRP(+) neurons were not significantly labeled. Dissociated Mrgprd(+) DRG neurons from mice expressing one or two copies of ChR2-Venus could be activated in vitro as evidenced by light-evoked currents and action potentials. In addition, illumination of Mrgprd-ChR2-Venus(+) axon terminals in spinal cord slices evoked EPSCs in half of all SG neurons. Within this subset, Mrgprd(+) neurons were monosynaptically connected to most known classes of SG neurons, including radial, tonic central, transient central, vertical, and antenna cells. This cellular diversity ruled out the possibility that Mrgprd(+) neurons innervate a dedicated class of SG neuron. Our findings set broad constraints on the types of spinal neurons that process afferent input from Mrgprd(+) polymodal nociceptors.

Pubmed ID: 19846708 RIS Download

Mesh terms: Animals | Biophysics | Calcitonin Gene-Related Peptide | Cells, Cultured | Electric Stimulation | Excitatory Postsynaptic Potentials | Ganglia, Spinal | Green Fluorescent Proteins | In Vitro Techniques | Lectins | Membrane Potentials | Mice | Mice, Inbred C57BL | Mice, Transgenic | Nerve Net | Nociceptors | Patch-Clamp Techniques | Photic Stimulation | Receptors, G-Protein-Coupled | Rhodopsin | Sensory Receptor Cells | Substantia Gelatinosa

Research resources used in this publication

None found

Research tools detected in this publication

None found

Data used in this publication

None found

Associated grants

  • Agency: NINDS NIH HHS, Id: P30NS045892
  • Agency: NINDS NIH HHS, Id: R01 NS060725
  • Agency: NINDS NIH HHS, Id: R01 NS060725-01
  • Agency: NINDS NIH HHS, Id: R01 NS060725-02
  • Agency: NINDS NIH HHS, Id: R01 NS060725-03
  • Agency: NINDS NIH HHS, Id: R01 NS060725-04
  • Agency: NINDS NIH HHS, Id: R01NS060725

Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.