Evidence for the absence of visceral pain in C57BL6/N mice subjected to therapeutically relevant O3/O2-pneumoperitoneum

Lab Anim. 2017 Feb;51(1):17-23. doi: 10.1177/0023677216636832. Epub 2016 Jul 9.

Abstract

Each different gas that is used to induce a pneumoperitoneum (PP) exhibits individual effects within the peritoneal cavity. This might include adverse effects such as pain and/or inflammatory reactions. The acute effects of ozonized oxygen (O3/O2), a highly oxidative gas mixture, after being insufflated into the peritoneal cavity are analysed in this study. Using the abdominal constriction response ('writhing') assay of chemical nociception in C57BL6/N mice, O3/O2-PP was found not to be associated with visible pain responses and did not alter the c-fos expression in the spinal cord. In addition, mRNA expression levels of the pro-inflammatory cytokines, interleukin (IL)-1β and IL-6, were found unaltered in the spleen 2 h after insufflation. In conclusion, O3/O2-PP is free of adverse pain and does not trigger inflammatory immune responses.

Keywords: cytokine; ozone; pain; pneumoperitoneum; refinement.

MeSH terms

  • Animals
  • Cytokines / genetics
  • Cytokines / metabolism
  • Female
  • Gene Expression* / drug effects
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Oxygen / pharmacology
  • Ozone / pharmacology*
  • Pneumoperitoneum / chemically induced
  • Pneumoperitoneum / physiopathology
  • Proto-Oncogene Proteins c-fos / genetics
  • Proto-Oncogene Proteins c-fos / metabolism
  • Spinal Cord / drug effects
  • Spinal Cord / metabolism
  • Visceral Pain / etiology
  • Visceral Pain / physiopathology*

Substances

  • Cytokines
  • Proto-Oncogene Proteins c-fos
  • Ozone
  • Oxygen