Abstract
It has been found that heterodimers of kappa- and delta-opioid receptors can occur in vitro, but it has been unclear whether they also occur in intact animals. In the present study we examined whether kappa-delta heterodimers might occur in vivo by staining for these receptors with two-color fluorescence immunocytochemistry. Sections of rat spinal cord were double-stained using rabbit anti-kappa opioid receptor combined with rat anti-delta-opioid receptor. It was found that axons in the superficial dorsal horn of the spinal cord were double-labeled. In addition, structures within axonal varicosities were sometimes double-labeled. We conclude that single axons, and single structures within axons, express both kappa- and delta-opioid receptors. These observations are consistent with heterodimers of these receptors existing in vivo.
Original language | English (US) |
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Pages (from-to) | 151-154 |
Number of pages | 4 |
Journal | Neuroscience Letters |
Volume | 298 |
Issue number | 3 |
DOIs | |
State | Published - Feb 9 2001 |
Bibliographical note
Funding Information:These studies were supported by PHS grants DA 09642 and DA 05466 from the National Institute on Drug Abuse.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
Keywords
- Analgesia
- Heterodimers
- Immunofluorescence
- Kappa2-opioid receptor
- Marginal zone
- Pain
- Primary afferents
- Substantia gelatinosa