Double in situ hybridization study on coexistence of μ-, δ- and κ-opioid receptor mRNAs with preprotachykinin A mRNA in the rat dorsal root ganglia

doi:10.1016/0169-328X(94)00290-U

Molecular Brain Research

Volume 30, Issue 2, June 1995, Pages 203-210

https://doi.org/10.1016/0169-328X(94)00290-U Get rights and content

Abstract

Coexistence of the mRNA for each subtype of opioid receptor (OPR) with the mRNA for preprotachykinin A (PPTA), a precursor protein of substance P (SP), in the rat dorsal root ganglia was examined by double in situ hybridization technique. About 90% and 30% of PPTA mRNA-positive neurons expressed μ- and κ-OPR mRNAs at high level, respectively. However, only about 3% of PPTA mRNA-positive neurons expressed δ-OPR mRNA at high level. These results suggest that μ- and κ-OPRs exist on most of and a part of the primary afferent terminals containing SP, respectively. On the other hand, among the neurons which highly expressed μ-, δ- or κ-OPR mRNA, PPTA mRNA was not expressed in about 58%, 95% or 24% of those neurons, respectively. These findings suggest the possibility that OPRs co-exist with other neurotransmitters and/or neuromodulators than SP in the primary afferent neurons.

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Citation Excerpt :
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Research reportDouble in situ hybridization study on coexistence of μ-, δ- and κ-opioid receptor mRNAs with preprotachykinin A mRNA in the rat dorsal root ganglia

Abstract

Peptides

Pain

Mol. Brain Res.

FEBS Lett.

Neuropharmacology

Biochem. Biophys. Res. Commun.

Brain Res.

Neuroscience

Eur. J. Pharmacol.

Neurosci. Lett.

Neurosci. Res.

FEBS Lett.

Neurosci. Lett.

Brain Res.

Brain Res.

Brain Res.

Research report
Double in situ hybridization study on coexistence of μ-, δ- and κ-opioid receptor mRNAs with preprotachykinin A mRNA in the rat dorsal root ganglia