Human and canine prostates contained exclusively proenkephalin-derived opioid nerve fibers — no dynorphin or endorphin nerves — concentrated in the dorsolateral stroma.
Enkephalin-only innervationThe prostate has a single opioid peptide family, not the three found in the brain
What the researchers found
Prostatic opioid innervation comes exclusively from proenkephalin-derived peptides. No prodynorphin or pro-opiomelanocortin products were detected in either species.
Why it matters
This shows the prostate has a selective opioid nerve supply that may help regulate smooth muscle tone and blood flow. Understanding this could be relevant to prostate conditions.
How the study worked
Immunohistochemistry using polyclonal antisera against multiple opioid peptides was applied to prostate tissue from juvenile humans, adult humans, and adult dogs.
What this study cannot tell us
This was an observational tissue study. It shows which peptides are present but not what they do. Sample sizes were small, typical for detailed histological studies.
How to read the evidence
Preliminary cross-sectional study with human and canine tissue — good cross-species validation.
When this study was published
Published in 1989 — established the opioid nerve supply of the prostate.
The bigger picture
The prostate has its own opioid nerve supply that could influence urinary symptoms, ejaculation, and prostate disease. This may be relevant to opioid medication effects on urological function.
Questions still open
- Do prostatic opioid nerves contribute to BPH symptoms?
- Could opioid receptors be targeted for prostate disease treatment?
Common questions
Do opioid drugs affect the prostate?
Why only enkephalins and not other opioids?
Read the original research
Regional distribution of opioidergic nerves in human and canine prostates.
The Prostate, 14(3), 279-88
Citation
Aumüller, G; Jungblut, T; Malek, B; Konrad, S; Weihe, E. (1989). Regional distribution of opioidergic nerves in human and canine prostates.. The Prostate, 14(3), 279-88.