| First Author | Wang HB | Year | 2010 |
| Journal | Proc Natl Acad Sci U S A | Volume | 107 |
| Issue | 29 | Pages | 13117-22 |
| PubMed ID | 20615975 | Mgi Jnum | J:162307 |
| Mgi Id | MGI:4818695 | Doi | 10.1073/pnas.1008382107 |
| Citation | Wang HB, et al. (2010) Coexpression of delta- and mu-opioid receptors in nociceptive sensory neurons. Proc Natl Acad Sci U S A 107(29):13117-22 |
| abstractText | Morphine-induced analgesia and antinociceptive tolerance are known to be modulated by interaction between delta-opioid receptors (DORs) and mu-opioid receptors (MORs) in the pain pathway. However, evidence for expression of DORs in nociceptive small-diameter neurons in dorsal root ganglia (DRG) and for coexistence of DORs with MORs and neuropeptides has recently been challenged. We now report, using in situ hybridization, single-cell PCR, and immunostaining, that DORs are widely expressed not only in large DRG neurons but in small ones and coexist with MORs in peptidergic small DRG neurons, with protachykinin-dependent localization in large dense-core vesicles. Importantly, both DOR and MOR agonists reduce depolarization-induced Ca(2+) currents in single small DRG neurons and inhibit afferent C-fiber synaptic transmission in the dorsal spinal cord. Thus, coexistence of DORs and MORs in small DRG neurons is a basis for direct interaction of opioid receptors in modulation of nociceptive afferent transmission and opioid analgesia. |
